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How to Use GRANT Statement in PostgreSQL

In PostgreSQL, users can access and override the privileges/rights of the database objects through the “GRANT” statement.

How to Use REVOKE Privileges in PostgreSQL

In PostgreSQL, the “REVOKE” statement is quite helpful in revoking the granted privileges from single or multiple roles.

How to Drop Roles in PostgreSQL

In Postgres, the DROP ROLE statement is used to drop an existing role with its attributes. In the case of dependent objects, the DROP OWNED statement is used.

How to Show Users in PostgreSQL

In PostgreSQL, the “\du” and “\du+” statements are used to show the list of users along with their attributes and descriptions.

How to Drop Schema in PostgreSQL

To drop a schema in Postgres, the DROP SCHEMA statement is used. A schema is a collection of several objects, so dropping a schema will drop all the objects present in it.


PostgreSQL offers an “ALTER SCHEMA” statement that is used to modify the schema’s definition, such as altering the schema’s owner, renaming a schema, etc.

How to Rename a Schema in PostgreSQL

In PostgreSQL, the “ALTER SCHEMA” statement is used with the collaboration of the “RENAME TO” statement to rename a particular schema.

How to Create Schema in PostgreSQL

In PostgreSQL, the “CREATE SCHEMA” statement is used to create a schema. A schema is a namespace that offers various objects, such as tables, views, indexes etc.

How to Create Roles in PostgreSQL

In PostgreSQL, the CREATE ROLE statement is used with different role attributes to create a role with specific privileges such as SUPERUSER, CONNECTION LIMIT, etc.


Postgres doesn’t offer the “IF NOT EXISTS” option for the INSERT query. Alternatively, you can use the subquery to check the existence of a specific record.