Catalog Reference

The SQreamDB database uses a schema called sqream_catalog that contains information about database objects such as tables, columns, views, and permissions. Some additional catalog tables are used primarily for internal analysis and may differ across SQreamDB versions.

What Information Does the Schema Contain?

The schema contains data management tables with information about structure and management of database elements, including tables, schemas, queries, and permissions, and physical storage and organization of data tables of extents, chunk columns, chunks, and delete predicates.

How to Get Table Information?

To get the information stored on a table, use this syntax, as in this example of working with the parameters table:

SELECT * FROM sqream_catalog.parameters;

To get the table ddl, use this syntax, as in this example of working with the parameters table:

SELECT get_ddl('sqream_catalog.parameters');

Database Management Tables

Database Object	Table
Clustering Keys	clustering_keys
Columns	columns, external_table_columns
Databases	databases
Parameters	parameters
Permissions	table_permissions, database_permissions, schema_permissions, permission_types, udf_permissions, sqream_catalog.table_default_permissions
Queries	savedqueries
Roles	roles, role_memberships
Schemas	schemas
Tables	tables, external_tables
Views	views
User Defined Functions	user_defined_functions

Data Storage and Organization Tables

Database Object	Table
Extents	Shows extents
Chunk columns	Shows chunks_columns
Chunks	Shows chunks
Delete predicates	Shows delete_predicates. For more information, see Deleting Data