Data Definition Language (DDL)

Data Definition Language (DDL)#

Data Definition Language (DDL) statements define and change the structure of your data — virtual databases, schemas, tables, views, indexes, functions and roles. Because Querona virtualizes data, these structures are metadata mapped over the connected sources rather than physical storage; see Materialization for when they are materialized into a backing store.

Create#

Statement	Description
CREATE DATABASE	Creates a virtual database over a connection.
CREATE SCHEMA	Creates a schema in a virtual database.
CREATE TABLE	Creates a new table in the virtual database.
CREATE VIRTUAL TABLE	Creates a metadata-only virtual table that maps to a source object without copying data.
CREATE VIEW	Creates a view in the virtual database.
CREATE INDEX	Creates an index on a view.
CREATE FUNCTION	Creates a user-defined function (UDF).
CREATE ROLE	Creates a database role.
CREATE CREDENTIAL	Creates a server-level credential (identity + optional secret) shared by all databases on the cluster.
CREATE DATABASE SCOPED CREDENTIAL	Creates a database scoped credential (identity + optional secret) in the current virtual database.
CREATE MASTER KEY	Accepted for SQL Server compatibility; a no-op — no master key is persisted.

Alter#

Statement	Description
ALTER TABLE	Adds a column or constraint to a table, or renames it.
ALTER VIEW	Changes the definition of an existing view.
ALTER INDEX	Modifies an existing index.
ALTER CREDENTIAL	Resets a server-level credential’s identity and secret.
ALTER DATABASE SCOPED CREDENTIAL	Resets a database scoped credential’s identity and secret.

Drop#

Statement	Description
DROP DATABASE	Removes a virtual database.
DROP SCHEMA	Removes a schema.
DROP INDEX	Removes an index from a view.
DROP FUNCTION	Removes a user-defined function.
DROP CREDENTIAL	Removes a server-level credential from the server.
DROP DATABASE SCOPED CREDENTIAL	Removes a database scoped credential from the current virtual database.
DROP MASTER KEY	Accepted for SQL Server compatibility; a no-op.

Sensitivity classification#

Statement	Description
SENSITIVITY CLASSIFICATION	Adds or removes a data-sensitivity classification (label and information type) on table columns.