Here is a list of SQL commands and what they do, these would be used in some injection methods and of course legitimate sql functions.
On thier own they wont exploit anything but eventually youl find an exploit that needs these and they are good to know for injection or just to better understand how SQL works.
ABORT -- abort the current transaction ALTER DATABASE -- change a database ALTER GROUP -- add users to a group or remove users from a group ALTER TABLE -- change the definition of a table ALTER TRIGGER -- change the definition of a trigger ALTER USER -- change a database user account ANALYZE -- collect statistics about a database BEGIN -- start a transaction block CHECKPOINT -- force a transaction log checkpoint CLOSE -- close a cursor CLUSTER -- cluster a table according to an index COMMENT -- define or change the comment of an object COMMIT -- commit the current transaction COPY -- copy data between files and tables CREATE AGGREGATE -- define a new aggregate function CREATE CAST -- define a user-defined cast CREATE CONSTRAINT TRIGGER -- define a new constraint trigger CREATE CONVERSION -- define a user-defined conversion CREATE DATABASE -- create a new database CREATE DOMAIN -- define a new domain CREATE FUNCTION -- define a new function CREATE GROUP -- define a new user group CREATE INDEX -- define a new index CREATE LANGUAGE -- define a new procedural language CREATE OPERATOR -- define a new operator CREATE OPERATOR CLASS -- define a new operator class for indexes CREATE RULE -- define a new rewrite rule CREATE SCHEMA -- define a new schema CREATE SEQUENCE -- define a new sequence generator CREATE TABLE -- define a new table CREATE TABLE AS -- create a new table from the results of a query CREATE TRIGGER -- define a new trigger CREATE TYPE -- define a new data type CREATE USER -- define a new database user account CREATE VIEW -- define a new view DEALLOCATE -- remove a prepared query DECLARE -- define a cursor DELETE -- delete rows of a table DROP AGGREGATE -- remove a user-defined aggregate function DROP CAST -- remove a user-defined cast DROP CONVERSION -- remove a user-defined conversion DROP DATABASE -- remove a database DROP DOMAIN -- remove a user-defined domain DROP FUNCTION -- remove a user-defined function DROP GROUP -- remove a user group DROP INDEX -- remove an index DROP LANGUAGE -- remove a user-defined procedural language DROP OPERATOR -- remove a user-defined operator DROP OPERATOR CLASS -- remove a user-defined operator class DROP RULE -- remove a rewrite rule DROP SCHEMA -- remove a schema DROP SEQUENCE -- remove a sequence DROP TABLE -- remove a table DROP TRIGGER -- remove a trigger DROP TYPE -- remove a user-defined data type DROP USER -- remove a database user account DROP VIEW -- remove a view END -- commit the current transaction EXECUTE -- execute a prepared query EXPLAIN -- show the execution plan of a statement FETCH -- retrieve rows from a table using a cursor GRANT -- define access privileges INSERT -- create new rows in a table LISTEN -- listen for a notification LOAD -- load or reload a shared library file LOCK -- explicitly lock a table MOVE -- position a cursor on a specified row of a table NOTIFY -- generate a notification PREPARE -- create a prepared query REINDEX -- rebuild corrupted indexes RESET -- restore the value of a run-time parameter to a default value REVOKE -- remove access privileges ROLLBACK -- abort the current transaction SELECT -- retrieve rows from a table or view SELECT INTO -- create a new table from the results of a query SET -- change a run-time parameter SET CONSTRAINTS -- set the constraint mode of the current transaction SET SESSION AUTHORIZATION -- set the session user identifier and the current user identifier of the current session SET TRANSACTION -- set the characteristics of the current transaction SHOW -- show the value of a run-time parameter START TRANSACTION -- start a transaction block TRUNCATE -- empty a table UNLISTEN -- stop listening for a notification UPDATE -- update rows of a table VACUUM -- garbage-collect and optionally analyze a database