DROP_STATISTICS_PARTITION

Removes statistical data on database projections previously generated by ANALYZE_STATISTICS_PARTITION. When you drop this data, the Vertica optimizer creates query plans using table-level statistics, if available, or default statistics.

This is a meta-function. You must call meta-functions in a top-level SELECT statement.

Behavior type

Syntax

DROP_STATISTICS_PARTITION ('[[database.]schema.]table', '[min-range-value]', '[max-range-value]' [, category [, '[column-list]'] )

Parameters

[database.]schema

Database and schema. The default schema is public. If you specify a database, it must be the current database.

table

Table on which to drop statistics.

min-range-value max-range-value

The minimum and maximum value of partition keys on which to drop statistics, where min-range-value must be ≤ max-range-value. If you supply empty strings for both parameters, Vertica drops all partition-level statistics for this table or the specified columns.

Important

The range of keys to drop must be equal to, or a superset of, the full range of partitions previously analyzed by ANALYZE_STATISTICS_PARTITION. If the range omits any analyzed partition, DROP_STATISTICS_PARTITION drops no statistics.

category

The category of statistics to drop, one of the following:

• BASE (default): Drop histograms and row counts (min/max column values, histogram).

• HISTOGRAMS: Drop only histograms. Row count statistics remain.

• ALL: Drop all statistics.

column-list

A comma-delimited list of columns in table, typically predicate columns. Vertica narrows the scope of dropped statistics to the specified columns. If you omit this parameter or supply an empty string, Vertica drops statistics on all columns.

Privileges

Non-superuser:

• Schema: USAGE

• Table: One of INSERT, DELETE, or UPDATE

See also