Exporting tables

Vertica function EXPORT_TABLES exports DDL for tables and related objects in the current database. The generated SQL includes all non-virtual table objects to which you have access. You can use this SQL to recreate tables and related non-virtual objects on a different cluster.

You execute EXPORT_TABLES as follows:

EXPORT_TABLES( ['[destination]' [, '[scope]']] )

The SQL script conforms to the following requirements:

• Only includes objects to which the user has access.

• Orders CREATE statements according to object dependencies so they can be recreated in the correct sequence. For example, if a table references a named sequence, a CREATE SEQUENCE statement precedes the CREATE TABLE statement. Similarly, a table's CREATE ACCESS POLICY statement follows the table's CREATE TABLE statement.

Setting export scope

The EXPORT_TABLES scope argument specifies the scope of the export operation:

Exporting all table objects

If you set the scope parameter to an empty string (''), EXPORT_TABLES exports all tables and their related objects. For example, the following call to EXPORT_TABLES exports all table objects in the VMart database to the specified output file.

 => SELECT EXPORT_TABLES(
      '/home/dbadmin/xtest/sql_tables_empty.sql', '');
            EXPORT_TABLES
-------------------------------------
 Catalog data exported successfully
(1 row)

The exported SQL includes the following types of statements, depending on what is required to recreate the tables and related objects, such as schemas, sequences and access policies:

• CREATE SCHEMA

• CREATE TABLE

• CREATE SEQUENCE

• CREATE ACCESS POLICY

• ALTER TABLE (to add foreign key constraints)

Exporting individual table objects

EXPORT_TABLES can specify a comma-separated list of tables and table-related objects such as sequences or schemas to export. The generated SQL script includes the CREATE statements for the specified objects and their dependent objects:

• CREATE SCHEMA

• CREATE TABLE

• CREATE SEQUENCE

• CREATE ACCESS POLICY

• ALTER TABLE (to add foreign keys)

For example, the following call to EXPORT_TABLES exports two VMart tables: store.store_sales_fact and store.store_dimension:

=> SELECT export_tables('','store.store_sales_fact, store.store_dimension');
                              export_tables
-------------------------------------------------------------------------

CREATE TABLE store.store_dimension
(
    store_key int NOT NULL,
    store_name varchar(64),
    store_number int,
    store_address varchar(256),
    store_city varchar(64),
    store_state char(2),
    store_region varchar(64),
    floor_plan_type varchar(32),
    photo_processing_type varchar(32),
    financial_service_type varchar(32),
    selling_square_footage int,
    total_square_footage int,
    first_open_date date,
    last_remodel_date date,
    number_of_employees int,
    annual_shrinkage int,
    foot_traffic int,
    monthly_rent_cost int,
    CONSTRAINT C_PRIMARY PRIMARY KEY (store_key) DISABLED
);

CREATE TABLE store.store_sales_fact
(
    date_key int NOT NULL,
    product_key int NOT NULL,
    product_version int NOT NULL,
    store_key int NOT NULL,
    promotion_key int NOT NULL,
    customer_key int NOT NULL,
    employee_key int NOT NULL,
    pos_transaction_number int NOT NULL,
    sales_quantity int,
    sales_dollar_amount int,
    cost_dollar_amount int,
    gross_profit_dollar_amount int,
    transaction_type varchar(16),
    transaction_time time,
    tender_type varchar(8)
);

ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_date FOREIGN KEY (date_key) references public.date_dimension (date_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_product FOREIGN KEY (product_key, product_version) references public.product_dimension (product_key, product_version);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_store FOREIGN KEY (store_key) references store.store_dimension (store_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_promotion FOREIGN KEY (promotion_key) references public.promotion_dimension (promotion_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_customer FOREIGN KEY (customer_key) references public.customer_dimension (customer_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_employee FOREIGN KEY (employee_key) references public.employee_dimension (employee_key);

The following call to EXPORT_TABLES specifies to export all tables in the VMart schema store :

=> select export_tables('','store');
                          export_tables
-----------------------------------------------------------------
CREATE SCHEMA store;

CREATE TABLE store.store_dimension
(
 ...
);

CREATE TABLE store.store_sales_fact
(
 ...
);

CREATE TABLE store.store_orders_fact
(
  ...
);

ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_date FOREIGN KEY (date_key) references public.date_dimension (date_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_product FOREIGN KEY (product_key, product_version) references public.product_dimension (product_key, product_version);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_store FOREIGN KEY (store_key) references store.store_dimension (store_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_promotion FOREIGN KEY (promotion_key) references public.promotion_dimension (promotion_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_customer FOREIGN KEY (customer_key) references public.customer_dimension (customer_key);
ALTER TABLE store.store_sales_fact ADD CONSTRAINT fk_store_sales_employee FOREIGN KEY (employee_key) references public.employee_dimension (employee_key);
ALTER TABLE store.store_orders_fact ADD CONSTRAINT fk_store_orders_product FOREIGN KEY (product_key, product_version) references public.product_dimension (product_key, product_version);
ALTER TABLE store.store_orders_fact ADD CONSTRAINT fk_store_orders_store FOREIGN KEY (store_key) references store.store_dimension (store_key);
ALTER TABLE store.store_orders_fact ADD CONSTRAINT fk_store_orders_vendor FOREIGN KEY (vendor_key) references public.vendor_dimension (vendor_key);
ALTER TABLE store.store_orders_fact ADD CONSTRAINT fk_store_orders_employee FOREIGN KEY (employee_key) references public.employee_dimension (employee_key);

(1 row)

See also

• Exporting objects
• Exporting the catalog