Configuration parameters

• 1: General parameters
• 2: Azure parameters
• 3: Constraints parameters
• 4: Database Designer parameters
• 5: Eon Mode parameters
• 6: Epoch management parameters
• 7: Google Cloud Storage parameters
• 8: Hadoop parameters
• 9: Internationalization parameters
• 10: Kafka user-defined session parameters
• 11: Kerberos parameters
• 12: Machine learning parameters
• 13: Memory management parameters
• 14: Monitoring parameters
• 15: Numeric precision parameters
• 16: Profiling parameters
• 17: Projection parameters
• 18: S3 parameters
• 19: SNS parameters
• 20: Security parameters
• 21: Stored procedure parameters
• 22: Text search parameters
• 23: Tuple mover parameters

=> SELECT parameter_name, current_value, default_value, allowed_levels, change_requires_restart
      FROM configuration_parameters  WHERE parameter_name ILIKE '%partitioncount%';
    parameter_name    | current_value | default_value | allowed_levels | change_requires_restart
----------------------+---------------+---------------+----------------+-------------------------
 MaxPartitionCount    | 1024          | 1024          | NODE, DATABASE | f
 ActivePartitionCount | 1             | 1             | NODE, DATABASE | f
(2 rows)

1 - General parameters

The following parameters configure basic database operations. Query the CONFIGURATION_PARAMETERS system table to determine what levels (node, session, user, database) are valid for a given parameter.

ApplyEventsDuringSALCheck

Boolean, specifies whether Vertica uses catalog events to filter out dropped corrupt partitions during node startup. Dropping corrupt partitions can speed node recovery.

When disabled (0), Vertica reports corrupt partitions, but takes no action. Leaving corrupt partitions in place can reset the current projection checkpoint epoch to the epoch before the corruption occurred.

This parameter has no effect on unpartitioned tables.

Default: 0

ApportionedFileMinimumPortionSizeKB

Specifies the minimum portion size (in kilobytes) for use with apportioned file loads. Vertica apportions a file load across multiple nodes only if:

• The load can be divided into portions at least equaling this value.

• EnableApportionedFileLoad and EnableApportionLoad are set to 1 (enabled).

See also EnableApportionLoad and EnableApportionedFileLoad.

Default: 1024

BlockedSocketGracePeriod

Sets how long a session socket remains blocked while awaiting client input or output for a given query. See Handling session socket blocking.

Default: None (Socket blocking can continue indefinitely.)

CatalogCheckpointPercent

Specifies the threshold at which a checkpoint is created for the database catalog.

By default, this parameter is set to 50 (percent), so when transaction logs reach 50% of the size of the last checkpoint, Vertica adds a checkpoint. Each checkpoint demarcates all changes to the catalog since the last checkpoint.

Default: 50 (percent)

ClusterSequenceCacheMode

Boolean, specifies whether the initiator node requests cache for other nodes in a cluster, and then sends cache to other nodes along with the execution plan, one of the following.

• 1 (enabled): Initiator node requests cache.

• 0: (disabled): All nodes request their own cache.

See Distributing sequences.

Default: 1 (enabled)

CompressCatalogOnDisk

Whether to compress the size of the catalog on disk, one of the following:

• 0: Do not compress.

• 1: Compress checkpoints, but not logs.

• 2: Compress checkpoints and logs.

This parameter is most effective if the catalog disk partition is small (<50 GB) and the metadata is large (hundreds of tables, partitions, or nodes).

Default: 1

CompressNetworkData

Boolean, specifies whether to compress all data sent over the internal network when enabled (set to 1). This compression speeds up network traffic at the expense of added CPU load. If the network is throttling database performance, enable compression to correct the issue.

Default: 0

CopyFaultTolerantExpressions

Boolean, indicates whether to report record rejections during transformations and proceed (true) or abort COPY operations if a transformation fails.

Default: 0 (false)

CopyFromVerticaWithIdentity

Allows COPY FROM VERTICA and EXPORT TO VERTICA to load values into IDENTITY columns. The destination IDENTITY column is not incremented automatically. To disable the default behavior, set this parameter to 0 (zero).

Default: 1

DatabaseHeartbeatInterval

Determines the interval (in seconds) at which each node performs a health check and communicates a heartbeat. If a node does not receive a message within five times of the specified interval, the node is evicted from the cluster. Setting the interval to 0 disables the feature.

See Automatic eviction of unhealthy nodes.

Default: 120

DefaultArrayBinarySize

The maximum binary size, in bytes, for an unbounded collection, if a maximum size is not specified at creation time.

Default: 65000

DefaultResourcePoolForUsers

Resource pool that is assigned to the profile of a new user, whether created in Vertica or LDAP. This pool is also assigned to users when their assigned resource pool is dropped.

You can set DefaultResourcePoolForUsers only to a global resource pool; attempts to set it to a subcluster resource pool return with an error.

Note

If an LDAP user is merged with an existing Vertica user, the resource pool setting on the existing user remains unchanged.

For details, see User resource allocation.

Default: GENERAL

DefaultTempTableLocal

Boolean, specifies whether CREATE TEMPORARY TABLE creates a local or global temporary table, one of the following:

• 0: Create global temporary table.

• 1: Create local temporary table.

For details, see Creating temporary tables.

Default: 0

DivideZeroByZeroThrowsError

Boolean, specifies whether to return an error if a division by zero operation is requested:

• 0: Return 0.

• 1: Returns an error.

Default: 1

EnableApportionedChunkingInDefaultLoadParser

Boolean, specifies whether to enable the built-in parser for delimited files to take advantage of both apportioned load and cooperative parse for potentially better performance.

Default: 1 (enable)

EnableApportionedFileLoad

Boolean, specifies whether to enable automatic apportioning across nodes of file loads using COPY FROM VERTICA. Vertica attempts to apportion the load if:

• This parameter and EnableApportionLoad are both enabled.

• The parser supports apportioning.

• The load is divisible into portion sizes of at least the value of ApportionedFileMinimumPortionSizeKB.

Setting this parameter does not guarantee that loads will be apportioned, but disabling it guarantees that they will not be.

See Distributing a load.

Default: 1 (enable)

EnableApportionLoad

Boolean, specifies whether to enable automatic apportioning across nodes of data loads using COPY...WITH SOURCE. Vertica attempts to apportion the load if:

• This parameter is enabled.

• The source and parser both support apportioning.

Setting this parameter does not guarantee that loads will be apportioned, but disabling it guarantees that they will not be.

For details, see Distributing a load.

Default: 1 (enable)

EnableBetterFlexTypeGuessing

Boolean, specifies whether to enable more accurate type guessing when assigning data types to non-string keys in a flex table __raw__ column with COMPUTE_FLEXTABLE_KEYS or COMPUTE_FLEXTABLE_KEYS_AND_BUILD_VIEW. If this parameter is disabled (0), Vertica uses a limited set of Vertica data type assignments.

Default: 1 (enable)

EnableCooperativeParse

Boolean, specifies whether to implement multi-threaded parsing capabilities on a node. You can use this parameter for both delimited and fixed-width loads.

Default: 1 (enable)

EnableForceOuter

Boolean, specifies whether Vertica uses a table's force_outer value to implement a join. For more information, see Controlling join inputs.

Default: 0 (forced join inputs disabled)

EnableMetadataMemoryTracking

Boolean, specifies whether to enable Vertica to track memory used by database metadata in the METADATA resource pool.

Default: 1 (enable)

EnableResourcePoolCPUAffinity

Boolean, specifies whether Vertica aligns queries to the resource pool of the processing CPU. When disabled (0), queries run on any CPU, regardless of the CPU_AFFINITY_SET of the resource pool.

Default: 1

EnableStrictTimeCasts

Specifies whether all cast failures result in an error.

Default: 0 (disable)

EnableUniquenessOptimization

Boolean, specifies whether to enable query optimization that is based on guaranteed uniqueness of column values. Columns that can be guaranteed to include unique values include:

• Columns that are defined with IDENTITY constraints

• Primary key columns where key constraints are enforced

• Columns that are constrained to unique values, either individually or as a set

Default: 1 (enable)

EnableWithClauseMaterialization

Superseded by WithClauseMaterialization.

ExternalTablesExceptionsLimit

Determines the maximum number of COPY exceptions and rejections allowed when a SELECT statement references an external table. Set to -1 to remove any exceptions limit. See Querying external tables.

Default: 100

FailoverToStandbyAfter

Specifies the length of time that an active standby node waits before taking the place of a failed node.

This parameter is set to an interval literal.

Default: None

FencedUDxMemoryLimitMB

Sets the maximum amount of memory, in megabytes (MB), that a fenced-mode UDF can use. If a UDF attempts to allocate more memory than this limit, that attempt triggers an exception. For more information, see Fenced and unfenced modes.

Default: -1 (no limit)

FlexTableDataTypeGuessMultiplier

Specifies a multiplier that the COMPUTE_FLEXTABLE_KEYS and COMPUTE_FLEXTABLE_KEYS_AND_BUILD_VIEW functions use when assigning a data type and column width for the flex keys table. Both functions assign each key a data type, and multiply the longest key value by this factor to estimate column width. This value is not used to calculate the width of any real columns in a flex table.

Default: 2.0

FlexTableRawSize

Specifies the default column width for the __raw__ column of new flex tables, a value between 1 and 32000000, inclusive.

Default: 130000

ForceUDxFencedMode

When enabled (1), forces all UDxs that support fenced mode to run in fenced mode even if their definition specified NOT FENCED.

Default: 0

HTTPServerPortOffset

Controls the offset for the HTTPS port. The default HTTPS port is 8443, the sum of the client port (5433) and default HTTPServerPortOffset (3010).

Caution

This parameter should not be changed without support guidance.

Default: 3010

IcebergPathMapping

For external tables using Iceberg data, a map of URI prefixes used by Iceberg to prefixes accessible to Vertica. The value is a JSON object:

'{"source-prefix":"new-prefix"[,...]}'

Specify prefixes only (up through port number), not complete paths.

IdleTimeoutInitializingConnectionsMs

The length of time (in milliseconds) that the server waits before timing out, during each step in connection initialization. After connection initialization, the session is created.

Default: 10000

JavaBinaryForUDx

Sets the full path to the Java executable that Vertica uses to run Java UDxs. See Installing Java on Vertica hosts.

JoinDefaultTupleFormat

Specifies how to size VARCHAR column data when joining tables on those columns, and buffers accordingly, one of the following:

• fixed: Use join column metadata to size column data to a fixed length, and buffer accordingly.

• variable: Use the actual length of join column data, so buffer size varies for each join.

Default: fixed

KeepAliveIdleTime

Length (in seconds) of the idle period before the first TCP keepalive probe is sent to ensure that the client is still connected. If set to 0, Vertica uses the kernel's tcp_keepalive_time parameter setting.

Default: 0

KeepAliveProbeCount

Number of consecutive keepalive probes that must go unacknowledged by the client before the client connection is considered lost and closed. If set to 0, Vertica uses the kernel's tcp_keepalive_probes parameter setting.

Default: 0

KeepAliveProbeInterval

Time interval (in seconds) between keepalive probes. If set to 0, Vertica uses the kernel's tcp_keepalive_intvl parameter setting.

Default: 0

LockTimeout

Specifies in seconds how long a table waits to acquire a lock.

Default: 300

LoadSourceStatisticsLimit

Specifies the maximum number of sources per load operation that are profiled in the LOAD_SOURCES system table. Set it to 0 to disable profiling.

Default: 256

MaxBundleableROSSizeKB

Specifies the minimum size, in kilobytes, of an independent ROS file. Vertica bundles storage container ROS files below this size into a single file. Bundling improves the performance of any file-intensive operations, including backups, restores, and mergeouts.

If you set this parameter to a value of 0, Vertica bundles .fdb and .pidx files without bundling other storage container files.

Default: 1024

MaxClientSessions

Determines the maximum number of client sessions that can run on a single node of the database. The default value allows for five additional administrative logins. These logins prevent DBAs from being locked out of the system if non-dbadmin users reach the login limit.

Tip

Setting this parameter to 0 prevents new client sessions from being opened while you are shutting down the database. Restore the parameter to its original setting after you restart the database. For details, see Managing Sessions.

Default: 50 user logins and 5 additional administrative logins

ObjectStoreGlobStrategy

For partitioned external tables in object stores, the strategy to use for expanding globs before pruning partitions:

• Flat: COPY fetches a list of all full object names with a given prefix, which can incur latency if partitions are numerous or deeply nested.

• Hierarchical: COPY fetches object names one partition layer at a time, allowing earlier pruning but possibly requiring more calls to the object store when queries are not selective or there are not many partittion directory levels.

For details, see Partitions on Object Stores.

Default: Flat

ParquetMetadataCacheSizeMB

Size of the cache used for metadata when reading Parquet data. The cache uses local TEMP storage.

Default: 4096

PatternMatchingUseJit

Boolean, specifies whether to enables just-in-time compilation (to machine code) of regular expression pattern matching functions used in queries. Enabling this parameter can usually improve pattern matching performance on large tables. The Perl Compatible Regular Expressions (PCRE) pattern-match library evaluates regular expressions. Restart the database for this parameter to take effect.

See also Regular expression functions.

Default: 1 (enable)

PatternMatchStackAllocator

Boolean, specifies whether to override the stack memory allocator for the pattern-match library. The Perl Compatible Regular Expressions (PCRE) pattern-match library evaluates regular expressions. Restart the database for this parameter to take effect.

See also Regular expression functions.

Default: 1 (enable override)

TerraceRoutingFactor

Specifies whether to enable or disable terrace routing on any Enterprise Mode large cluster that implements rack-based fault groups.

• To enable, set as follows:
  where: * numRackNodes: Number of nodes in a rack * numRacks: Number of racks in the cluster
• To disable, set to a value so large that terrace routing cannot be enabled for the largest clusters—for example, 1000.

For details, see Terrace routing.

Default: 2

TransactionIsolationLevel

Changes the isolation level for the database. After modification, Vertica uses the new transaction level for every new session. Existing sessions and their transactions continue to use the original isolation level.

See also Change transaction isolation levels.

Default: READ COMMITTED

TransactionMode

Specifies whether transactions are in read/write or read-only modes. Read/write is the default. Existing sessions and their transactions continue to use the original isolation level.

Default: READ WRITE

UDxFencedBlockTimeout

Specifies the number of seconds to wait for output before aborting a UDx running in Fenced and unfenced modes. If the server aborts a UDx for this reason, it produces an error message similar to "ERROR 3399: Failure in UDx RPC call: timed out in receiving a UDx message". If you see this error frequently, you can increase this limit. UDxs running in fenced mode do not run in the server process, so increasing this value does not impede server performance.

Default: 60

UseLocalTzForParquetTimestampConversion

Boolean, specifies whether to do timezone conversion when reading Parquet files. Hive version 1.2.1 introduced an option to localize timezones when writing Parquet files. Previously it wrote them in UTC and Vertica adjusted the value when reading the files.

Set to 0 if Hive already adjusted the timezones.

Default: 1 (enable conversion)

UseServerIdentityOverUserIdentity

Boolean, specifies whether to ignore user-supplied credentials for non-Linux file systems and always use a USER storage location to govern access to data. See Creating a Storage Location for USER Access.

Default: 0 (disable)

WithClauseMaterialization

Boolean, specifies whether to enable materialization of WITH clause results. When materialization is enabled (1), Vertica evaluates each WITH clause once and stores results in a temporary table.

For WITH queries with complex types, temp relations are disabled.

Note

You can enable materialization of a given WITH clause with the hint ENABLE_WITH_CLAUSE_MATERIALIZATION.

Default: 0 (disable)

WithClauseRecursionLimit

Specifies the maximum number of times a WITH RECURSIVE clause iterates over the content of its own result set before it exits. For details, see WITH clause recursion.

Important

Be careful to set WithClauseRecursionLimit only as high as needed to traverse the deepest hierarchies. Vertica sets no limit on this parameter; however, a high value can incur considerable overhead that adversely affects performance and exhausts system resources.

If a high recursion count is required, then consider enabling materialization. For details, see WITH RECURSIVE Materialization.

Default: 8

2 - Azure parameters

Use the following parameters to configure reading from Azure blob storage. For more information about reading data from Azure, see Azure Blob Storage object store.

For external tables using highly partitioned data in an object store, see the ObjectStoreGlobStrategy configuration parameter and Partitions on Object Stores.

AzureStorageCredentials

Collection of JSON objects, each of which specifies connection credentials for one endpoint. This parameter takes precedence over Azure managed identities.

The collection must contain at least one object and may contain more. Each object must specify at least one of accountName or blobEndpoint, and at least one of accountKey or sharedAccessSignature.

• accountName: If not specified, uses the label of blobEndpoint.
• blobEndpoint: Host name with optional port (host:port). If not specified, uses account.blob.core.windows.net.
• accountKey: Access key for the account or endpoint.
• sharedAccessSignature: Access token for finer-grained access control, if being used by the Azure endpoint.

AzureStorageEndpointConfig

Collection of JSON objects, each of which specifies configuration elements for one endpoint. Each object must specify at least one of accountName or blobEndpoint.

• accountName: If not specified, uses the label of blobEndpoint.
• blobEndpoint: Host name with optional port (host:port). If not specified, uses account.blob.core.windows.net.
• protocol: HTTPS (default) or HTTP.
• isMultiAccountEndpoint: true if the endpoint supports multiple accounts, false otherwise (default is false). To use multiple-account access, you must include the account name in the URI. If a URI path contains an account, this value is assumed to be true unless explicitly set to false.

3 - Constraints parameters

The following configuration parameters control how Vertica evaluates and enforces constraints. All parameters are set at the database level through ALTER DATABASE.

Three of these parameters—EnableNewCheckConstraintsByDefault, EnableNewPrimaryKeysByDefault, and EnableNewUniqueKeysByDefault—can be used to enforce CHECK, PRIMARY KEY, and UNIQUE constraints, respectively. For details, see Constraint enforcement.

EnableNewCheckConstraintsByDefault

Boolean parameter, set to 0 or 1:

• 0: Disable enforcement of new CHECK constraints except where the table DDL explicitly enables them.

• 1 (default): Enforce new CHECK constraints except where the table DDL explicitly disables them.

EnableNewPrimaryKeysByDefault

Boolean parameter, set to 0 or 1:

• 0 (default): Disable enforcement of new PRIMARY KEY constraints except where the table DDL explicitly enables them.

• 1: Enforce new PRIMARY KEY constraints except where the table DDL explicitly disables them.

Note

Vertica recommends enforcing constraints PRIMARY KEY and UNIQUE together.

EnableNewUniqueKeysByDefault

Boolean parameter, set to 0 or 1:

• 0 (default): Disable enforcement of new UNIQUE constraints except where the table DDL explicitly enables them.

• 1: Enforce new UNIQUE constraints except where the table DDL explicitly disables them.

MaxConstraintChecksPerQuery

Sets the maximum number of constraints that ANALYZE_CONSTRAINTS can handle with a single query:

• -1 (default): No maximum set, ANALYZE_CONSTRAINTS uses a single query to evaluate all constraints within the specified scope.

• Integer > 0: The maximum number of constraints per query. If the number of constraints to evaluate exceeds this value, ANALYZE_CONSTRAINTS handles it with multiple queries.

For details, see Distributing Constraint Analysis.

4 - Database Designer parameters

The following table describes the parameters for configuring the Vertica Database Designer.

DBDCorrelationSampleRowCount

Minimum number of table rows at which Database Designer discovers and records correlated columns.

Default: 4000

DBDLogInternalDesignProcess

Enables or disables Database Designer logging.

Default: 0 (False)

DBDUseOnlyDesignerResourcePool

Enables use of the DBD pool by the Vertica Database Designer.

When set to false, design processing is mostly contained by the user's resource pool, but might spill over into some system resource pools for less-intensive tasks

Default: 0 (False)

5 - Eon Mode parameters

The following parameters configure how the database operates when running in Eon Mode. Query the CONFIGURATION_PARAMETERS system table to determine what levels (node, session, user, database) are valid for a given parameter.

BackgroundDepotWarming

Specifies background depot warming behavior:

• 1: The depot loads objects while it is warming, and continues to do so in the background after the node becomes active and starts executing queries.

• 0: Node activation is deferred until the depot fetches and loads all queued objects

For details, see Depot Warming.

Default: 1

CatalogSyncInterval

Specifies in minutes how often the transaction log sync service syncs metadata to communal storage. If you change this setting, Vertica restarts the interval count.

Default: 5

DelayForDeletes

Specifies in hours how long to wait before deleting a file from communal storage. Vertica first deletes a file from the depot. After the specified time interval, the delete also occurs in communal storage.

Default: 0. Deletes the file from communal storage as soon as it is not in use by shard subscribers.

DepotOperationsForQuery

Specifies behavior when the depot does not contain queried file data, one of the following:

• ALL (default): Fetch file data from communal storage, if necessary displace existing files by evicting them from the depot.

• FETCHES: Fetch file data from communal storage only if space is available; otherwise, read the queried data directly from communal storage.

• NONE: Do not fetch file data to the depot, read the queried data directly from communal storage.

You can also specify query-level behavior with the hint DEPOT_FETCH.

ECSMode

String parameter that sets the strategy Vertica uses when dividing the data in a shard among subscribing nodes during an ECS-enabled query, one of the following:

• AUTO: Optimizer automatically determines the strategy to use.

• COMPUTE_OPTIMIZED: Force use of the compute-optimized strategy.

• IO_OPTIMIZED: Force use of the I/O-optimized strategy.

For details, see Manually choosing an ECS strategy.

Default: AUTO

ElasticKSafety

Boolean parameter that controls whether Vertica adjusts shard subscriptions due to the loss of a primary node:

• 1: When a primary node is lost, Vertica subscribes other primary nodes to the down node's shard subscriptions. This action helps reduce the chances of a database into going read-only mode due to loss of shard coverage.
• 0 : Vertica does not change shard subscriptions in reaction to the loss of a primary node.

Default: 1

For details, see Maintaining Shard Coverage.

EnableDepotWarmingFromPeers

Boolean parameter, specifies whether Vertica warms a node depot while the node is starting up and not ready to process queries:

• 1: Warm the depot while a node comes up.

• 0: Warm the depot only after the node is up.

For details, see Depot Warming.

Default: 0

FileDeletionServiceInterval

Specifies in seconds the interval between each execution of the reaper cleaner service task.

Default: 60 seconds

MaxDepotSizePercent

An integer value that specifies the maximum size of the depot as a percentage of disk size,

Default: 80

PreFetchPinnedObjectsToDepotAtStartup

If enabled (set to 1), a warming depot fetches objects that are pinned on its subcluster. For details, see Depot Warming.

Default: 0

ReaperCleanUpTimeoutAtShutdown

Specifies in seconds how long Vertica waits for the reaper to delete files from communal storage before shutting down. If set to a negative value, Vertica shuts down without waiting for the reaper.

Note

The reaper is a service task that deletes disk files.

Default: 300

StorageMergeMaxTempCacheMB

The size of temp space allocated per query to the StorageMerge operator for caching the data of S3 storage containers.

Note

The actual temp space that is allocated is the lesser of:

• StorageMergeMaxTempCacheMB

• A user's TEMPSPACECAP setting

• The session TEMPSPACECAP setting

For details, see Local caching of storage containers.

UseCommunalStorageForBatchDepotWarming

Boolean parameter, specifies whether where a node retrieves data when warming its depot:

• 1: Retrieve data from communal storage.

• 0: Retrieve data from a peer.

Note

The actual temp space that is allocated is the lesser of two settings:

Default: 1

Important

This parameter is for internal use only. Do not change it unless directed to do so by Vertica support.

UseDepotForReads

Boolean parameter, specifies whether Vertica accesses the depot to answer queries, or accesses only communal storage:

• 1: Vertica first searches the depot for the queried data; if not there, Vertica fetches the data from communal storage for this and future queries.

• 0: Vertica bypasses the depot and always obtains queried data from communal storage.

Note

Enable depot reads to improve query performance and support K-safety.

Default: 1

UseDepotForWrites

Boolean parameter, specifies whether Vertica writes loaded data to the depot and then uploads files to communal storage:

• 1: Write loaded data to the depot, upload files to communal storage.

• 0: Bypass the depot and always write directly to communal storage.

Default: 1

UsePeerToPeerDataTransfer

Boolean parameter, specifies whether Vertica pushes loaded data to other shard subscribers:

• 1: Send loaded data to all shard subscribers.

• 0: Do not push data to other shard subscribers.

Note

Setting to 1 helps improve performance when a node is down.

Default: 0

Important

This parameter is for internal use only. Do not change it unless directed to do so by Vertica support.

6 - Epoch management parameters

The following table describes the epoch management parameters for configuring Vertica.

AdvanceAHMInterval

Determines how frequently (in seconds) Vertica checks the history retention status.

AdvanceAHMInterval cannot be set to a value that is less than the EpochMapInterval.

Default: 180 (seconds)

AHMBackupManagement

Blocks the advancement of the Ancient History Mark (AHM). When this parameter is enabled, the AHM epoch cannot be later than the epoch of your latest full backup. If you advance the AHM to purge and delete data, do not enable this parameter.

Caution

Do not enable this parameter before taking full backups, as it would prevent the AHM from advancing.

Default: 0

EpochMapInterval

Determines the granularity of mapping between epochs and time available to historical queries. When a historical queries AT TIME T request is issued, Vertica maps it to an epoch within a granularity of EpochMapInterval seconds. It similarly affects the time reported for Last Good Epoch during Failure recovery. Note that it does not affect internal precision of epochs themselves.

Tip

Decreasing this interval increases the number of epochs saved on disk. Therefore, consider reducing the HistoryRetentionTime parameter to limit the number of history epochs that Vertica retains.

Default: 180 (seconds)

HistoryRetentionTime

Determines how long deleted data is saved (in seconds) as an historical reference. When the specified time since the deletion has passed, you can purge the data. Use the -1 setting if you prefer to use HistoryRetentionEpochs to determine which deleted data can be purged.

Note

The default setting of 0 effectively prevents the use of the Administration tools 'Roll Back Database to Last Good Epoch' option because the AHM remains close to the current epoch and a rollback is not permitted to an epoch prior to the AHM.

Tip

If you rely on the Roll Back option to remove recently loaded data, consider setting a day-wide window to remove loaded data. For example:

ALTER DATABASE DEFAULT SET HistoryRetentionTime = 86400;

Default: 0 (Data saved when nodes are down.)

HistoryRetentionEpochs

Specifies the number of historical epochs to save, and therefore, the amount of deleted data.

Unless you have a reason to limit the number of epochs, Vertica recommends that you specify the time over which deleted data is saved.

If you specify both History parameters, HistoryRetentionTime takes precedence. Setting both parameters to -1, preserves all historical data.

See Setting a purge policy.

Default: -1 (disabled)

7 - Google Cloud Storage parameters

Use the following parameters to configure reading from Google Cloud Storage (GCS) using COPY FROM. For more information about reading data from S3, see Specifying where to load data from.

For external tables using highly partitioned data in an object store, see the ObjectStoreGlobStrategy configuration parameter and Partitions on Object Stores.

GCSAuth

An ID and secret key to authenticate to GCS. You can set parameters globally and for the current session with ALTER DATABASE...SET PARAMETER and ALTER SESSION...SET PARAMETER, respectively. For extra security, do not store credentials in the database; instead, set it for the current session with ALTER SESSION. For example:

=> ALTER SESSION SET GCSAuth='ID:secret';

If you use a shared credential, set it in the database with ALTER DATABASE.

GCSEnableHttps

Specifies whether to use the HTTPS protocol when connecting to GCS, can be set only at the database level with ALTER DATABASE...SET PARAMETER.

Default: 1 (enabled)

GCSEndpoint

The connection endpoint address.

Default: storage.googleapis.com

8 - Hadoop parameters

The following table describes general parameters for configuring integration with Apache Hadoop. See Apache Hadoop integration for more information.

EnableHDFSBlockInfoCache

Boolean, whether to distribute block location metadata collected during planning on the initiator to all database nodes for execution. Distributing this metadata reduces name node accesses, and thus load, but can degrade database performance somewhat in deployments where the name node isn't contended. This performance effect is because the data must be serialized and distributed. Enable distribution if protecting the name node is more important than query performance; usually this applies to large HDFS clusters where name node contention is already an issue.

Default: 0 (disabled)

HadoopConfDir

Directory path containing the XML configuration files copied from Hadoop. The same path must be valid on every Vertica node. You can use the VERIFY_HADOOP_CONF_DIR meta-function to test that the value is set correctly. Setting this parameter is required to read data from HDFS.

For all Vertica users, the files are accessed by the Linux user under which the Vertica server process runs.

When you set this parameter, previously-cached configuration information is flushed.

You can set this parameter at the session level. Doing so overrides the database value; it does not append to it. For example:

  
=> ALTER SESSION SET HadoopConfDir='/test/conf:/hadoop/hcat/conf';

To append, get the current value and include it on the new path after your additions. Setting this parameter at the session level does not change how the files are accessed.

Default: obtained from environment if possible

HadoopFSAuthentication

How (or whether) to use Kerberos authentication with HDFS. By default, if KerberosKeytabFile is set, Vertica uses that credential for both Vertica and HDFS. Usually this is the desired behavior. However, if you are using a Kerberized Vertica cluster with a non-Kerberized HDFS cluster, set this parameter to "none" to indicate that Vertica should not use the Vertica Kerberos credential to access HDFS.

Default: "keytab" if KerberosKeytabFile is set, otherwise "none"

HadoopFSBlockSizeBytes

Block size to write to HDFS. Larger files are divided into blocks of this size.

Default: 64MB

HadoopFSNNOperationRetryTimeout

Number of seconds a metadata operation (such as list directory) waits for a response before failing. Accepts float values for millisecond precision.

Default: 6 seconds

HadoopFSReadRetryTimeout

Number of seconds a read operation waits before failing. Accepts float values for millisecond precision. If you are confident that your file system will fail more quickly, you can improve performance by lowering this value.

Default: 180 seconds

HadoopFSReplication

Number of replicas HDFS makes. This is independent of the replication that Vertica does to provide K-safety. Do not change this setting unless directed otherwise by Vertica support.

Default: 3

HadoopFSRetryWaitInterval

Initial number of seconds to wait before retrying read, write, and metadata operations. Accepts float values for millisecond precision. The retry interval increases exponentially with every retry.

Default: 3 seconds

HadoopFSTokenRefreshFrequency

How often, in seconds, to refresh the Hadoop tokens used to hold Kerberos tickets (see Token expiration).

Default: 0 (refresh when token expires)

HadoopFSWriteRetryTimeout

Number of seconds a write operation waits before failing. Accepts float values for millisecond precision. If you are confident that your file system will fail more quickly, you can improve performance by lowering this value.

Default: 180 seconds

HadoopImpersonationConfig

Session parameter specifying the delegation token or Hadoop user for HDFS access. See HadoopImpersonationConfig format for information about the value of this parameter and Proxy users and delegation tokens for more general context.

HDFSUseWebHDFS

Boolean, whether URLs in the hdfs scheme use WebHDFS instead of LibHDFS++ to access data.

Deprecated

This parameter is deprecated because LibHDFS++ is deprecated. In the future, Vertica will use WebHDFS for all hdfs URLs.

Default: 1 (enabled)

WebhdfsClientCertConf

mTLS configurations for accessing one or more WebHDFS servers. The value is a JSON string; each member has the following properties:

• nameservice: WebHDFS name service

• authority: host:port

• certName: name of a certificate defined by CREATE CERTIFICATE

nameservice and authority are mutually exclusive.

For example:

=> ALTER SESSION SET WebhdfsClientCertConf =
    '[{"authority" : "my.authority.com:50070", "certName" : "myCert"},
      {"nameservice" : "prod", "certName" : "prodCert"}]';

HCatalog Connector parameters

The following table describes the parameters for configuring the HCatalog Connector. See Using the HCatalog Connector for more information.

EnableHCatImpersonation

Boolean, whether the HCatalog Connector uses (impersonates) the current Vertica user when accessing Hive. If impersonation is enabled, the HCatalog Connector uses the Kerberos credentials of the logged-in Vertica user to access Hive data. Disable impersonation if you are using an authorization service to manage access without also granting users access to the underlying files. For more information, see Configuring security.

Default: 1 (enabled)

HCatalogConnectorUseHiveServer2

Boolean, whether Vertica internally uses HiveServer2 instead of WebHCat to get metadata from Hive.

Default: 1 (enabled)

HCatalogConnectorUseLibHDFSPP

Boolean, whether the HCatalog Connector should use the hdfs scheme instead of webhdfs with the HCatalog Connector.

Deprecated

Vertica uses the hdfs scheme by default. To use webhdfs, set the HDFSUseWebHDFS parameter.

Default: 1 (enabled)

HCatConnectionTimeout

The number of seconds the HCatalog Connector waits for a successful connection to the HiveServer2 (or WebHCat) server before returning a timeout error.

Default: 0 (Wait indefinitely)

HCatSlowTransferLimit

Lowest transfer speed (in bytes per second) that the HCatalog Connector allows when retrieving data from the HiveServer2 (or WebHCat) server. In some cases, the data transfer rate from the server to Vertica is below this threshold. In such cases, after the number of seconds specified in the HCatSlowTransferTime parameter pass, the HCatalog Connector cancels the query and closes the connection.

Default: 65536

HCatSlowTransferTime

Number of seconds the HCatalog Connector waits before testing whether the data transfer from the server is too slow. See the HCatSlowTransferLimit parameter.

Default: 60

9 - Internationalization parameters

The following table describes internationalization parameters for configuring Vertica.

DefaultIntervalStyle

Sets the default interval style to use. If set to 0 (default), the interval is in PLAIN style (the SQL standard), no interval units on output. If set to 1, the interval is in UNITS on output. This parameter does not take effect until the database is restarted.

Default: 0

DefaultSessionLocale

Sets the default session startup locale for the database. This parameter does not take effect until the database is restarted.

Default: en_US@collation=binary

EscapeStringWarning

Issues a warning when backslashes are used in a string literal. This can help locate backslashes that are being treated as escape characters so they can be fixed to follow the SQL standard-conforming string syntax instead.

Default: 1

StandardConformingStrings

Determines whether character string literals treat backslashes () as string literals or escape characters. When set to -1, backslashes are treated as string literals; when set to 0, backslashes are treated as escape characters.

Tip

To treat backslashes as escape characters, use the Extended string syntax

(E'...');

Default: -1

10 - Kafka user-defined session parameters

Set Vertica user-defined session parameters to configure Kafka SSL when not using a scheduler, using ALTER SESSION SET UDPARAMETER. The kafka-prefixed parameters configure SSL authentication for Kafka. For details, see TLS/SSL encryption with Kafka.

kafka_SSL_CA

The contents of the certificate authority certificate. For example:

=> ALTER SESSION SET UDPARAMETER kafka_SSL_CA='MIIBOQIBAAJBAIOL';

Default: none

kafka_SSL_Certificate

The contents of the SSL certificate. For example:

=> ALTER SESSION SET UDPARAMETER kafka_SSL_Certificate='XrM07O4dV/nJ5g';

This parameter is optional when the Kafka server's parameter ssl.client.auth is set to none or requested.

Default: none

kafka_SSL_PrivateKey_secret

The private key used to encrypt the session. Vertica does not log this information. For example:

=> ALTER SESSION SET UDPARAMETER kafka_SSL_PrivateKey_secret='A60iThKtezaCk7F';

This parameter is optional when the Kafka server's parameter ssl.client.auth is set to none or requested.

Default: none

kafka_SSL_PrivateKeyPassword_secret

The password used to create the private key. Vertica does not log this information.

For example:

ALTER SESSION SET UDPARAMETER kafka_SSL_PrivateKeyPassword_secret='secret';

This parameter is optional when the Kafka server's parameter ssl.client.auth is set to none or requested.

Default: none

kafka_Enable_SSL

Enables SSL authentication for Vertica-Kafka integration. For example:

=> ALTER SESSION SET UDPARAMETER kafka_Enable_SSL=1;
  

Default: 0

MaxSessionUDParameterSize

Sets the maximum length of a value in a user-defined session parameter. For example:

=> ALTER SESSION SET MaxSessionUDParameterSize = 2000
  

Default: 1000

Related topics

11 - Kerberos parameters

The following parameters let you configure the Vertica principal for Kerberos authentication and specify the location of the Kerberos keytab file.

KerberosEnableKeytabPermissionCheck

Whether the Vertica server verifies permissions on the keytab file. By default, the Vertica server verifies these permissions.

In a hybrid Kubernetes cluster, set this parameter to 0 so that there is no permissions check. Otherwise, Kerberos authentication fails because the keytab file is stored in a Secret, and the VerticaDB operator cannot verify permissions on a Secret.

Default: 1

KerberosHostname

Instance or host name portion of the Vertica Kerberos principal. For example:

vertica/host@EXAMPLE.COM

If you omit the optional KerberosHostname parameter, Vertica uses the return value from the function gethostname(). Assuming each cluster node has a different host name, those nodes will each have a different principal, which you must manage in that node's keytab file.

KerberosKeytabFile

Location of the keytab file that contains credentials for the Vertica Kerberos principal. By default, this file is located in /etc. For example:

KerberosKeytabFile=/etc/krb5.keytab

Note

• The principal must take the form KerberosServiceName/KerberosHostName@KerberosRealm

• The keytab file must be readable by the file owner who is running the process (typically the Linux dbadmin user assigned file permissions 0600).

KerberosRealm

Realm portion of the Vertica Kerberos principal. A realm is the authentication administrative domain and is usually formed in uppercase letters. For example:

vertica/hostEXAMPLE.COM

KerberosServiceName

Service name portion of the Vertica Kerberos principal. By default, this parameter is vertica. For example:

vertica/host@EXAMPLE.COM

Default: vertica

KerberosTicketDuration

Lifetime of the ticket retrieved from performing a kinit. The default is 0 (zero) which disables this parameter.

If you omit setting this parameter, the lifetime is determined by the default Kerberos configuration.

12 - Machine learning parameters

You use machine learning parameters to configure various aspects of machine learning functionality in Vertica.

MaxModelSizeKB

Sets the maximum size of models that can be imported. The sum of the size of files specified in the metadata.json file determines the model size. The unit of this parameter is KBytes. The native Vertica model (category=VERTICA_MODELS) is exempted from this limit. If you can export the model from Vertica, and the model is not altered while outside Vertica, you can import it into Vertica again.

The MaxModelSizeKB parameter can be set only by a superuser and only at the database level. It is visible only to a superuser. Its default value is 4GB, and its valid range is between 1KB and 64GB (inclusive).

Examples:

To set this parameter to 3KB:

=> ALTER DATABASE DEFAULT SET MaxModelSizeKB = 3;

To set this parameter to 64GB (the maximum allowed):

=> ALTER DATABASE DEFAULT SET MaxModelSizeKB = 67108864;

To reset this parameter to the default value:

=> ALTER DATABASE DEFAULT CLEAR MaxModelSizeKB;

Default: 4GB

13 - Memory management parameters

The following table describes parameters for managing Vertica memory usage.

MemoryPollerIntervalSec

Specifies in seconds how often the Vertica memory poller checks whether Vertica memory usage is below the thresholds of several configuration parameters (see below):

• MemoryPollerMallocBloatThreshold

• MemoryPollerReportThreshold

• MemoryPollerTrimThreshold

Important

To disable polling of all thresholds, set this parameter to 0. Doing so effectively disables automatic memory usage reporting and trimming.

Default: 2

MemoryPollerMallocBloatThreshold

Threshold of glibc memory bloat.

The memory poller calls glibc function malloc_info() to obtain the amount of free memory in malloc. It then compares MemoryPollerMallocBloatThreshold—by default, set to 0.3—with the following expression:

free-memory-in-malloc / RSS

If this expression evaluates to a value higher than MemoryPollerMallocBloatThreshold, the memory poller calls glibc function malloc_trim(). This function reclaims free memory from malloc and returns it to the operating system. Details on calls to malloc_trim() are written to system table MEMORY_EVENTS.

To disable polling of this threshold, set the parameter to 0.

Default: 0.3

MemoryPollerReportThreshold

Threshold of memory usage that determines whether the Vertica memory poller writes a report.

The memory poller compares MemoryPollerReportThreshold with the following expression:

RSS / available-memory

When this expression evaluates to a value higher than MemoryPollerReportThreshold—by default, set to 0.93, then the memory poller writes a report to MemoryReport.log, in the Vertica working directory. This report includes information about Vertica memory pools, how much memory is consumed by individual queries and session, and so on. The memory poller also logs the report as an event in system table MEMORY_EVENTS, where it sets EVENT_TYPE to MEMORY_REPORT.

To disable polling of this threshold, set the parameter to 0.

Default: 0.93

MemoryPollerTrimThreshold

Threshold for the memory poller to start checking whether to trim glibc-allocated memory.

The memory poller compares MemoryPollerTrimThreshold—by default, set to 0.83— with the following expression:

RSS / available-memory

If this expression evaluates to a value higher than MemoryPollerTrimThreshold, then the memory poller starts checking the next threshold—set in MemoryPollerMallocBloatThreshold—for glibc memory bloat.

To disable polling of this threshold, set the parameter to 0. Doing so also disables polling of MemoryPollerMallocBloatThreshold.

Default: 0.83

14 - Monitoring parameters

The following table describes parameters that control options for monitoring the Vertica database.

EnableDataCollector

Enables and disables the Data Collector, which is the Workload Analyzer's internal diagnostics utility. Affects all sessions on all nodes. Use 0 to turn off data collection.

Default: 1 (enabled)

SnmpTrapDestinationsList

Defines where Vertica sends traps for SNMP. See Configuring reporting for SNMP. For example:

=> ALTER DATABASE DEFAULT SET SnmpTrapDestinationsList = 'localhost 162 public';

Default: none

SnmpTrapsEnabled

Enables event trapping for SNMP. See Configuring reporting for SNMP.

Default: 0

SnmpTrapEvents

Define which events Vertica traps through SNMP. See Configuring reporting for SNMP. For example:

ALTER DATABASE DEFAULT SET SnmpTrapEvents = 'Low Disk Space, Recovery Failure';
  

Default: Low Disk Space, Read Only File System, Loss of K Safety, Current Fault Tolerance at Critical Level, Too Many ROS Containers, Node State Change, Recovery Failure, Stale Checkpoint, and CRC Mismatch.

SyslogEnabled

Enables event trapping for syslog. See Configuring reporting for syslog.

Default: 0

SyslogEvents

Defines events that generate a syslog entry. See Configuring reporting for syslog. For example:

ALTER DATABASE DEFAULT SET SyslogEvents = 'Low Disk Space, Recovery Failure';
  

Default: none

SyslogFacility

Defines which SyslogFacility Vertica uses. See Configuring reporting for syslog.

Default: user

15 - Numeric precision parameters

The following configuration parameters let you configure numeric precision for numeric data types. For more about using these parameters, seeNumeric data type overflow with SUM, SUM_FLOAT, and AVG.

AllowNumericOverflow

Boolean, set to one of the following:

• 1 (true): Allows silent numeric overflow. Vertica does not implicitly extend precision of numeric data types. Vertica ignores the value of NumericSumExtraPrecisionDigits.

• 0 (false): Vertica produces an overflow error, if a result exceeds the precision set by NumericSumExtraPrecisionDigits.

Default: 1 (true)

NumericSumExtraPrecisionDigits

An integer between 0 and 20, inclusive. Vertica produces an overflow error if a result exceeds the specified precision. This parameter setting only applies if AllowNumericOverflow is set to 0 (false).

Default: 6 (places beyond the DDL-specified precision)

16 - Profiling parameters

The following table describes the profiling parameters for configuring Vertica. See Profiling database performance for more information on profiling queries.

GlobalEEProfiling

Enables profiling for query execution runs in all sessions on all nodes.

Default: 0

GlobalQueryProfiling

Enables query profiling for all sessions on all nodes.

Default: 0

GlobalSessionProfiling

Enables session profiling for all sessions on all nodes.

Default: 0

SaveDCEEProfileThresholdUS

Sets in microseconds the query duration threshold for saving profiling information to system tables QUERY_CONSUMPTION and EXECUTION_ENGINE_PROFILES. You can set this parameter to a maximum value of 2147483647 (2³¹-1, or ~35.79 minutes).

Default: 60000000 (60 seconds)

17 - Projection parameters

The following configuration parameters help you manage projections.

AnalyzeRowCountInterval

Specifies how often Vertica checks the number of projection rows and whether the threshold set by ARCCommitPercentage has been crossed.

For more information, see Collecting database statistics.

Default: 86400 seconds (24 hours)

ARCCommitPercentage

Sets the threshold percentage of difference between the last-recorded aggregate projection row count and current row count for a given table. When the difference exceeds this threshold, Vertica updates the catalog with the current row count.

Default: 3 (percent)

ContainersPerProjectionLimit

Specifies how many ROS containers Vertica creates per projection before ROS pushback occurs.

Caution

Increasing this parameter's value can cause serious degradation of database performance. Vertica strongly recommends that you not modify this parameter without first consulting with Customer Support professionals.

Default: 1024

MaxAutoSegColumns

Specifies the number of columns (0 –1024) to use in an auto-projection's hash segmentation clause. Set to 0 to use all columns.

Default: 8

MaxAutoSortColumns

Specifies the number of columns (0 –1024) to use in an auto-projection's sort expression. Set to 0 to use all columns.

Default: 8

RebalanceQueryStorageContainers

By default, prior to performing a rebalance, Vertica performs a system table query to compute the size of all projections involved in the rebalance task. This query enables Vertica to optimize the rebalance to most efficiently utilize available disk space. This query can, however, significantly increase the time required to perform the rebalance.

By disabling the system table query, you can reduce the time required to perform the rebalance. If your nodes are low on disk space, disabling the query increases the chance that a node runs out of disk space. In that situation, the rebalance fails.

Default: 1 (enable)

RewriteQueryForLargeDim

If enabled (1), Vertica rewrites a SET USING or DEFAULT USING query during a REFRESH_COLUMNS operation by reversing the inner and outer join between the target and source tables. Doing so can optimize refresh performance in cases where the source data is in a table that is larger than the target table.

Important

Enable this parameter only if the SET USING source data is in a table that is larger than the target table. If the source data is in a table smaller than the target table, then enabling RewriteQueryForLargeDim can adversely affect refresh performance.

Default: 0

SegmentAutoProjection

Determines whether auto-projections are segmented if the table definition omits a segmentation clause. You can set this parameter at database and session scopes.

Default: 1 (create segmented auto projections)

18 - S3 parameters

Use the following parameters to configure reading from S3 file systems and on-premises storage with S3-compatible APIs, using COPY. For more information about reading data from S3, see S3 Object Store.

For external tables using highly partitioned data in an object store, see the ObjectStoreGlobStrategy configuration parameter and Partitions on Object Stores.

AWSAuth

ID and secret key for authentication. For extra security, do not store credentials in the database; use ALTER SESSION...SET PARAMETER to set this value for the current session only. If you use a shared credential, you can set it in the database with ALTER DATABASE...SET PARAMETER. For example:

=> ALTER SESSION SET AWSAuth='ID:secret';

In AWS, these arguments are named AccessKeyID and SecretAccessKey.

To use admintools create_db or revive_db for Eon Mode on-premises, create a configuration file called auth_params.conf with these settings:

AWSAuth = key:secret
  AWSEndpoint = IP:port

AWSCAFile

File name of the TLS server certificate bundle to use. Setting this parameter overrides the Vertica default CA bundle path specified in the SystemCABundlePath parameter.

If set, this parameter overrides the Vertica default CA bundle path specified in the SystemCABundlePath parameter.

=> ALTER DATABASE DEFAULT SET AWSCAFile = '/etc/ssl/ca-bundle.pem';

Default: system-dependent

AWSCAPath

Path Vertica uses to look up TLS server certificates. The file name of the TLS server certificate bundle to use.

If set, this parameter overrides the Vertica default CA bundle path specified in the SystemCABundlePath parameter.

=> ALTER DATABASE DEFAULT SET AWSCAPath = '/etc/ssl/';

Default: system-dependent

AWSEnableHttps

Boolean, specifies whether to use the HTTPS protocol when connecting to S3, can be set only at the database level with ALTER DATABASE. If you choose not to use TLS, this parameter must be set to 0.

Default: 1 (enabled)

AWSEndpoint

Endpoint to use when interpreting S3 URLs, set as follows.

Important

Do not include http(s):// for AWS endpoints.

• AWS: hostname_or_ip:port_number.

• AWS with a FIPS-compliant S3 Endpoint: S3_hostname and enable virtual addressing:

  Important

  Do not include http(s)://

  AWSEndpoint = s3-fips.dualstack.us-east-1.amazonaws.com
  S3EnableVirtualAddressing = 1
  

• On-premises/Pure: IP address of the Pure Storage server. If using admintools create_db or revive_db, create configuration file auth_params.conf and include these settings:

  awsauth = key:secret
        awsendpoint = IP:port
  

• When AWSEndpoint is not set, the default behavior is to use virtual-hosted request URLs.

Default: s3.amazonaws.com

AWSLogLevel

Log level, one of the following:

• OFF

• FATAL

• ERROR

• WARN

• INFO

• DEBUG

• TRACE

**Default:**ERROR

AWSRegion

AWS region containing the S3 bucket from which to read files. This parameter can only be configured with one region at a time. If you need to access buckets in multiple regions, change the parameter each time you change regions.

If you do not set the correct region, you might experience a delay before queries fail because Vertica retries several times before giving up.

Default: us-east-1

AWSSessionToken

Temporary security token generated by running the get-session-token command, which generates temporary credentials you can use to configure multi-factor authentication.

Set this parameter in a user session using ALTER SESSION. You can set this parameter at the database level, but be aware that session tokens are temporary. When the token expires, any attempt to access AWS fails.

Note

If you use session tokens at the session level, you must set all parameters at the session level, even if some of them are set at the database level. Use ALTER SESSION to set session parameters.

AWSStreamingConnectionPercentage

Controls the number of connections to the communal storage that Vertica uses for streaming reads. In a cloud environment, this setting helps prevent streaming data from communal storage using up all available file handles. It leaves some file handles available for other communal storage operations.

Due to the low latency of on-premises object stores, this option is unnecessary for an Eon Mode database that uses on-premises communal storage. In this case, disable the parameter by setting it to 0.

S3BucketConfig

Contains S3 bucket configuration information as a JSON object with the following properties. Each property other than the bucket name has a corresponding configuration parameter (shown in parentheses). If both the property in S3BucketConfig and the configuration parameter are set, the S3BucketConfig property takes precedence.

Properties:

• bucket: Name of the bucket

• region (AWSRegion): Name of the region

• protocol (AWSEnableHttps): Connection protocol, either http or https

• endpoint (AWSEndpoint): Endpoint URL or IP address

• enableVirtualAddressing (S3BucketCredentials): Whether to rewrite the S3 URL to use a virtual hosted path

• requesterPays (S3RequesterPays): Whether requester (instead of bucket owner) pays the cost of accessing data on the bucket

• serverSideEncryption (S3ServerSideEncryption): Encryption algorithm if using SSE-S3 or SSE-KMS, one of AES256, aws:kms, or an empty string

• sseCustomerAlgorithm (S3SseCustomerAlgorithm): Encryption algorithm if using SSE-C; must be AES256

• sseCustomerKey (S3SseCustomerKey): Key if using SSE-C encryption, either 32-character plaintext or 44-character base64-encoded

• sseKmsKeyId (S3SseKmsKeyId): Key ID if using SSE-KMS encryption

The configuration properties for a given bucket might differ based on its type. For example, the following S3BucketConfig is for an AWS bucket AWSBucket and a Pure Storage bucket PureStorageBucket. AWSBucket doesn't specify an endpoint, so Vertica uses the value of AWSEndpoint, which defaults to s3.amazonaws.com:

ALTER DATABASE DEFAULT SET S3BucketConfig=
'[
    {
        "bucket": "AWSBucket",
        "region": "us-east-2",
        "protocol": "https",
        "requesterPays": true
    },
    {
        "bucket": "PureStorageBucket",
        "endpoint": "pure.mycorp.net:1234",
        "protocol": "http",
        "enableVirtualAddressing": false
    }
]';

S3BucketCredentials

Contains credentials for accessing an S3 bucket. Each property in S3BucketCredentials has an equivalent parameter (shown in parentheses). When set, S3BucketCredentials takes precedence over both AWSAuth and AWSSessionToken.

Providing credentials for more than one bucket authenticates to them simultaneously, allowing you to perform cross-endpoint joins, export from one bucket to another, etc.

Properties:

• bucket: Name of the bucket

• accessKey: Access key for the bucket (the ID in AWSAuth)

• secretAccessKey: Secret access key for the bucket (the secret in AWSAuth)

• sessionToken: Session token, only used when S3BucketCredentials is set at the session level (AWSSessionToken)

For example, the following S3BucketCredentials is for an AWS bucket AWSBucket and a Pure Storage bucket PureStorageBucket and sets all possible properties:

ALTER SESSION SET S3BucketCredentials='
[
    {
        "bucket": "AWSBucket",
        "accessKey": "<AK0>",
        "secretAccessKey": "<SAK0>",
        "sessionToken": "1234567890"
    },
    {
        "bucket": "PureStorageBucket",
        "accessKey": "<AK1>",
        "secretAccessKey": "<SAK1>"
    }
]';

This parameter is only visible to the superuser. Users can set this parameter at the session level with ALTER SESSION.

S3EnableVirtualAddressing

Boolean, specifies whether to rewrite S3 URLs to use virtual-hosted paths. For example, if you use AWS, the S3 URLs change to bucketname.s3.amazonaws.com instead of s3.amazonaws.com/bucketname. This configuration setting takes effect only when you have specified a value for AWSEndpoint.

If you set AWSEndpoint to a FIPS-compliant S3 Endpoint, you must enable S3EnableVirtualAddressing in auth_params.conf:

AWSEndpoint = s3-fips.dualstack.us-east-1.amazonaws.com
S3EnableVirtualAddressing = 1

The value of this parameter does not affect how you specify S3 paths.

Default: 0 (disabled)

Note

As of September 30, 2020, AWS requires virtual address paths for newly created buckets.

S3RequesterPays

Boolean, specifies whether requester (instead of bucket owner) pays the cost of accessing data on the bucket. When true, the bucket owner is only responsible for paying the cost of storing the data, rather than all costs associated with the bucket; must be set in order to access S3 buckets configured as Requester Pays buckets. By setting this property to true, you are accepting the charges for accessing data. If not specified, the default value is false.

S3ServerSideEncryption

String, encryption algorithm to use when reading or writing to S3. The value depends on which type of encryption at rest is configured for S3:

• AES256: Use for SSE-S3 encryption

• aws:kms: Use for SSE-KMS encryption

• Empty string (""): No encryption

SSE-C encryption does not use this parameter. Instead, see S3SseCustomerAlgorithm.

For details on using SSE parameters, see S3 object store.

Default: "" (no encryption)

S3SseCustomerAlgorithm

String, the encryption algorithm to use when reading or writing to S3 using SSE-C encryption. The only supported values are AES256 and "".

For SSE-S3 and SSE-KMS, instead use S3ServerSideEncryption.

Default: "" (no encryption)

S3SseCustomerKey

If using SSE-C encryption, the client key for S3 access.

S3SseKmsKeyId

If using SSE-KMS encryption, the key identifier (not the key) to pass to the Key Management Server. Vertica must have permission to use the key, which is managed through KMS.

19 - SNS parameters

The following parameters configure Amazon Simple Notification Service (SNS) notifiers. These parameters can only be set at the database level and some, if unset, fall back to their equivalent S3 parameters.

Notifiers must be disabled and then reenabled for these parameters to take effect:

=> ALTER NOTIFIER sns_notifier DISABLE;
=> ALTER NOTIFIER sns_notifier ENABLE;

20 - Security parameters

Use these client authentication configuration parameters and general security parameters to configure TLS.

• To configure Vertica for client-server TLS, see Configuring client-server TLS.

• To configure JDBC and ODBC clients for TLS, see Configuring TLS for JDBC clients and Configuring TLS for ODBC Clients.

• For Kerberos-related parameters, see Kerberos parameters.

Database parameters

DataSSLParams

This parameter has been deprecated. Use the data_channel TLS Configuration instead.

Enables encryption using SSL on the data channel. The value of this parameter is a comma-separated list of the following:

• An SSL certificate (chainable)

• The corresponding SSL private key

• The SSL CA (Certificate Authority) certificate.

You should set EncryptSpreadComm before setting this parameter.

In the following example, the SSL Certificate contains two certificates, where the certificate for the non-root CA verifies the certificate for the cluster. This is called an SSL Certificate Chain.

=> ALTER DATABASE DEFAULT SET PARAMETER DataSSLParams =
'----BEGIN CERTIFICATE-----<certificate for Cluster>-----END CERTIFICATE-----
-----BEGIN CERTIFICATE-----<certificate for non-root CA>-----END CERTIFICATE-----,
-----BEGIN RSA PRIVATE KEY-----<private key for Cluster>-----END RSA PRIVATE KEY-----,
-----BEGIN CERTIFICATE-----<certificate for public CA>-----END CERTIFICATE-----';

DefaultIdleSessionTimeout

Indicates a default session timeout value for all users where IDLESESSIONTIMEOUT is not set. For example:

=> ALTER DATABASE DEFAULT SET defaultidlesessiontimeout = '300 secs';
  

DHParams

Deprecated

This parameter has been deprecated and will be removed in a future release.

String, a Diffie-Hellman group of at least 2048 bits in the form:

 -----BEGIN DH PARAMETERS-----...-----END DH PARAMETERS-----

You can generate your own or use the pre-calculated Modular Exponential (MODP) Diffie-Hellman groups specified in RFC 3526.

Changes to this parameter do not take effect until you restart the database.

Default: RFC 3526 2048-bit MODP Group 14:

  
-----BEGIN DH PARAMETERS-----MIIBCAKCAQEA///////////
JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxObIlFKCHmONAT
d75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjf
tawv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKF
jvwWY2kg2HFXTmmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQd
wlpZtZww1Tkq8mATxdGwIyhghfDKQXkYuNs474553LBgOhgObJ4O
i7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq5RXSJhiY+gUQFXK
OWoqsqmj//////////wIBAg==-----END DH PARAMETERS-----
  

DisableInheritedPrivileges

Boolean, whether to disable privilege inheritance at the database level (enabled by default).

DoUserSpecificFilteringInSysTables

Boolean, specifies whether a non-superuser can view details of another user:

• 0: Users can view details of other users.

• 1: Users can only view details about themselves.

Default: 0

EnableAllRolesOnLogin

Boolean, specifies whether to automatically enable all roles granted to a user on login:

• 0: Do not automatically enable roles

• 1: Automatically enable roles. With this setting, users do not need to run SET ROLE.

Default: 0 (disable)

EnabledCipherSuites

Specifies which SSL cipher suites to use for secure client-server communication. Changes to this parameter apply only to new connections.

Default: Vertica uses the Microsoft Schannel default cipher suites. For more information, see the Schannel documentation.

EnableOAuth2JITCleanup

If enabled, users created by just-in-time OAuth provisioning are automatically dropped if the user does not log in after the number of days specified by OAuth2UserExpiredInterval.

To view provisioned users, see USERS.

Default: 0 (disable)

EncryptSpreadComm

Enables Spread encryption on the control channel, set to one of the following strings:

• vertica: Specifies that Vertica generates the Spread encryption key for the database cluster.

• aws-kms|key-name, where key-name is a named key in the iAWS Key Management Service (KMS). On database restart, Vertica fetches the named key from the KMS instead of generating its own.

If the parameter is empty, Spread communication is unencrypted. In general, you should enable this parameter before modifying other security parameters.

Enabling this parameter requires database restart.

GlobalHeirUsername

A string that specifies which user inherits objects after their owners are dropped. This setting ensures preservation of data that would otherwise be lost.

Set this parameter to one of the following string values:

• Empty string: Objects of dropped users are removed from the database.

• username: Reassigns objects of dropped users to username. If username does not exist, Vertica creates that user and sets GlobalHeirUsername to it.

• <auto>: Reassigns objects of dropped LDAP or just-in-time-provisioned users to the dbadmin user. The brackets (< and >) are required for this option.

For more information about usage, see Examples.

Default: <auto>

ImportExportTLSMode

When using CONNECT TO VERTICA to connect to another Vertica cluster for import or export, specifies the degree of stringency for using TLS. Possible values are:

• PREFER: Try TLS but fall back to plaintext if TLS fails.

• REQUIRE: Use TLS and fail if the server does not support TLS.

• VERIFY_CA: Require TLS (as with REQUIRE), and also validate the other server's certificate using the CA specified by the "server" TLS Configuration's CA certificates (in this case, "ca_cert" and "ica_cert"):

  => SELECT name, certificate, ca_certificate, mode FROM tls_configurations WHERE name = 'server';
    name  |   certificate    |   ca_certificate   |   mode
  --------+------------------+--------------------+-----------
   server | server_cert      | ca_cert,ica_cert   | VERIFY_CA
  (1 row)
  

• VERIFY_FULL: Require TLS and validate the certificate (as with VERIFY_CA), and also validate the server certificate's hostname.

• REQUIRE_FORCE, VERIFY_CA_FORCE, and VERIFY_FULL_FORCE: Same behavior as REQUIRE, VERIFY_CA, and VERIFY_FULL, respectively, and cannot be overridden by CONNECT TO VERTICA.

Default: PREFER

InternodeTLSConfig

The TLS Configuration to use for internode encryption.

For example:

=> ALTER DATABASE DEFAULT SET InternodeTLSConfig = my_tls_config;

Default: data_channel

LDAPAuthTLSConfig

The TLS Configuration to use for TLS with LDAP authentication.

For example:

=> ALTER DATABASE DEFAULT SET LDAPAuthTLSConfig = my_tls_config;

Default: ldapauth

LDAPLinkTLSConfig

The TLS Configuration to use for TLS for the LDAP Link service.

For example:

=> ALTER DATABASE DEFAULT SET LDAPLinkTLSConfig = my_tls_config;

Default: ldaplink

OAuth2JITClient

The client/application name that contains Vertica roles in the identity provider. The Vertica roles under resource_access.OAuth2JITClient.roles are automatically granted to and set as default roles for users created by just-in-time provisioning. Roles that do not exist in Vertica are ignored.

For details, see Just-in-time user provisioning.

Default: vertica

OAuth2UserExpiredInterval

If EnableOAuthJITCleanup is enabled, users created by just-in-time OAuth provisioning are automatically dropped after not logging in for the number of days specified by OAuth2UserExpiredInterval. The number of days the user has not logged in is calculated relative to the LAST_LOGIN_TIME column in the USERS system table.

Note

The LAST_LOGIN_TIME as recorded by the USERS system table is not persistent; if the database is restarted, the LAST_LOGIN_TIME for users created by just-in-time user provisioning is set to the database start time (this appears as an empty value in LAST_LOGIN_TIME).

You can view the database start time by querying the DATABASES system table:

=> SELECT database_name, start_time FROM databases;
 database_name |          start_time
---------------+-------------------------------
 VMart         | 2023-02-06 14:26:50.630054-05
(1 row)

Default: 14

PasswordLockTimeUnit

The time units for which an account is locked by PASSWORD_LOCK_TIME after FAILED_LOGIN_ATTEMPTS, one of the following:

• 'd': days (default)

• 'h': hours

• 'm': minutes

• 's': seconds

For example, to configure the default profile to lock user accounts for 30 minutes after three unsuccessful login attempts:

  
=> ALTER DATABASE DEFAULT SET PasswordLockTimeUnit = 'm'
=> ALTER PROFILE DEFAULT LIMIT PASSWORD_LOCK_TIME 30;
  

RequireFIPS

Boolean, specifies whether the FIPS mode is enabled:

• 0 (disable)

• 1: (enable)

On startup, Vertica automatically sets this parameter from the contents of the file crypto.fips_enabled. You cannot modify this parameter.

For details, see FIPS compliance for the Vertica server.

Default: 0

SecurityAlgorithm

Sets the algorithm for the function that hash authentication uses, one of the following:

• SHA512

• MD5

For example:

=> ALTER DATABASE DEFAULT SET SecurityAlgorithm = 'SHA512';

Default: SHA512

ServerTLSConfig

The TLS Configuration to use for client-server TLS.

For example:

=> ALTER DATABASE DEFAULT SET ServerTLSConfig = my_tls_config;

Default: server

SystemCABundlePath

The absolute path to a certificate bundle of trusted CAs. This CA bundle is used when establishing TLS connections to external services such as AWS or Azure through their respective SDKs and libcurl. The CA bundle file must be in the same location on all nodes.

If this parameter is empty, Vertica searches the "standard" paths for the CA bundles, which differs between distributions:

• Red Hat-based: /etc/pki/tls/certs/ca-bundle.crt
• Debian-based: /etc/ssl/certs/ca-certificates.crt
• SUSE: /var/lib/ca-certificates/ca-bundle.pem

Example:

=> ALTER DATABASE DEFAULT SET SystemCABundlePath = 'path/to/ca_bundle.pem';
  

Default: Empty

TLS parameters

To set your Vertica database's TLSMode, private key, server certificate, and CA certificate(s), see TLS configurations. In versions prior to 11.0.0, these parameters were known as EnableSSL, SSLPrivateKey, SSLCertificate, and SSLCA, respectively.

Examples

Set the database parameter GlobalHeirUsername:

=> \du
      List of users
 User name | Is Superuser
-----------+--------------
 Joe       | f
 SuzyQ     | f
 dbadmin   | t
(3 rows)

=> ALTER DATABASE DEFAULT SET PARAMETER GlobalHeirUsername='SuzyQ';
ALTER DATABASE
=>  \c - Joe
You are now connected as user "Joe".
=> CREATE TABLE t1 (a int);
CREATE TABLE

=> \c
You are now connected as user "dbadmin".
=> \dt t1
             List of tables
 Schema | Name | Kind  | Owner | Comment
--------+------+-------+-------+---------
 public | t1   | table | Joe   |
(1 row)

=> DROP USER Joe;
NOTICE 4927:  The Table t1 depends on User Joe
ROLLBACK 3128:  DROP failed due to dependencies
DETAIL:  Cannot drop User Joe because other objects depend on it
HINT:  Use DROP ... CASCADE to drop the dependent objects too
=> DROP USER Joe CASCADE;
DROP USER
=> \dt t1
             List of tables
 Schema | Name | Kind  | Owner | Comment
--------+------+-------+-------+---------
 public | t1   | table | SuzyQ |
(1 row)

21 - Stored procedure parameters

The following parameters configure the behavior of stored procedures and triggers.

EnableNestedStoredProcedures

Boolean, whether to enable nested stored procedures.

Default: 0

EnableStoredProcedureScheduler

Boolean, whether to enable the scheduler. For details, see Scheduled execution.

Default: 1

PLvSQLCoerceNull

Boolean, whether to allow NULL-to-false type coercion to improve compatibility with PLpgSQL. For details, see PL/pgSQL to PL/vSQL migration guide.

Default: 0

22 - Text search parameters

You can configure Vertica for text search using the following parameter.

TextIndexMaxTokenLength

Controls the maximum size of a token in a text index.

For example:

ALTER DATABASE database_name SET PARAMETER TextIndexMaxTokenLength=760;

If the parameter is set to a value greater than 65000 characters, then the tokenizer truncates the token at 65000 characters.

Caution

Avoid setting this parameter near its maximum value, 65000. Doing so can result in a significant decrease in performance. For optimal performance, set this parameter to the maximum token value of your tokenizer.

Default: 128 (characters)

23 - Tuple mover parameters

These parameters control how the Tuple Mover operates.

ActivePartitionCount

Sets the number of active partitions. The active partitions are those most recently created. For example:

=> ALTER DATABASE DEFAULT SET ActivePartitionCount = 2;

For information about how the Tuple Mover treats active and inactive partitions during a mergeout operation, see Partition mergeout.

Default: 1

CancelTMTimeout

When partition, copy table, and rebalance operations encounter a conflict with an internal Tuple Mover job, those operations attempt to cancel the conflicting Tuple Mover job. This parameter specifies the amount of time, in seconds, that the blocked operation waits for the Tuple Mover cancellation to take effect. If the operation is unable to cancel the Tuple Mover job within limit specified by this parameter, the operation displays an error and rolls back.

Default: 300

EnableTMOnRecoveringNode

Boolean, specifies whether Tuple Mover performs mergeout activities on nodes with a node state of RECOVERING. Enabling Tuple Mover reduces the number of ROS containers generated during recovery. Having fewer than 1024 ROS containers per projection allows Vertica to maintain optimal recovery performance.

Default: 1 (enabled)

MaxMrgOutROSSizeMB

Specifies in MB the maximum size of ROS containers that are candidates for mergeout operations. The Tuple Mover avoids merging ROS containers that are larger than this setting.

Note

After a rebalance operation, Tuple Mover groups ROS containers in batches that are smaller than MaxMrgOutROSSizeMB. ROS containers that are larger than MaxMrgOutROSSizeMB are merged individually

Default: -1 (no maximum limit)

MergeOutInterval

Specifies in seconds how frequently the Tuple Mover checks the mergeout request queue for pending requests:

1. If the queue contains mergeout requests, the Tuple Mover does nothing and goes back to sleep.

2. If the queue is empty, the Tuple Mover:

   • Processes pending storage location move requests.

   • Checks for new unqueued purge requests and adds them to the queue.

   It then goes back to sleep.

Default: 600

PurgeMergeoutPercent

Specifies as a percentage the threshold of deleted records in a ROS container that invokes an automatic mergeout operation, to purge those records. Vertica only counts the number of 'aged-out' delete vectors—that is, delete vectors that are as 'old' or older than the ancient history mark (AHM) epoch.

This threshold applies to all ROS containers for non-partitioned tables. It also applies to ROS containers of all inactive partitions. In both cases, aged-out delete vectors are permanently purged from the ROS container.

Note

This configuration parameter only applies to automatic mergeout operations. It does not apply to manual mergeout operations that are invoked by calling meta-functions DO_TM_TASK('mergeout') and PURGE.

Default: 20 (percent)