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.
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.