Type of SQL Statements

 

Type of SQL statements are divided into five different categories: Data definition language (DDL), Data manipulation language (DML), Data Control Language (DCL), Transaction Control Statement (TCS), Session Control Statements (SCS).

Data Definition Language (DDL)

Data definition statement are use to define the database structure or table.

Statement	Description
CREATE	Create new database/table.
ALTER	Modifies the structure of database/table.
DROP	Deletes a database/table.
TRUNCATE	Remove all table records including allocated table spaces.
RENAME	Rename the database/table.

Data Manipulation Language (DML)

Data manipulation statement are use for managing data within table object.

Statement	Description
SELECT	Retrieve data from the table.
INSERT	Insert data into a table.
UPDATE	Updates existing data with new data within a table.
DELETE	Deletes the records rows from the table.
MERGE	MERGE (also called UPSERT) statements to INSERT new records or UPDATE existing records depending on condition matches or not.
LOCK TABLE	LOCK TABLE statement to lock one or more tables in a specified mode. Table access denied to a other users for the duration of your table operation.
CALL EXPLAIN PLAN	Statements are supported in PL/SQL only for executed dynamically. CALL a PL/SQL program or EXPLAIN PATH access the data path.

Data Control Language (DCL)

Data control statement are use to give privileges to access limited data.

Statement	Description
GRANT	Gives privileges to user for accessing database data.
REVOKE	Take back for given privileges.
ANALYZE	ANALYZE statement to collect statistics information about index, cluster, table.
AUDIT	To track the occurrence of a specific SQL statement or all SQL statements during the user sessions.
COMMENT	Write comment to the data table.

Transaction Control Statement (TCS)

Transaction control statement are use to apply the changes permanently save into database.

Statement	Description
COMMIT	Permanent work save into database.
ROLLBACK	Restore database to original form since the last COMMIT.
SAVEPOINT	Create SAVEPOINT for later use ROLLBACK the new changes.
SET TRANSACTION	SET TRANSACTION command set the transaction properties such as read-write/read only access.

PL/SQL Transaction commit, rollback, savepoint, autocommit, Set Transaction read more.

Session Control Statement (SCS)

Session control statement are manage properties dynamically of a user session.

Statement	Description
ALTER SESSION	ALTER SESSION statement to modify conditions or parameters that are affect to your database connection.
SET ROLE	SET ROLE statement to enable or disable the roles that are currently enabled for the session.