The statements like SELECT, INSERT, UPDATE, DELETE are used to manipulate the table, while ALTER TABLE, CREATE TABLE and DELETE TABLE are used to manage table.
The most important statement for database testing is the SELECT statement, which returns data rows from one or multiple tables that satisfies a given set of criteria.
You may need to use other DML (Data Manipulation Language) statements like INSERT, UPDATE and DELTE to manage your test data.
You may also need to use DDL (Data Definition Language) statements like CREATE TABLE, ALTER TABLE, and DROP TABLE to manage your test tables.
You may also need to some other commands to view table structures, column definitions, indexes, constraints and store procedures.