SQL components |
CREATE - used to create objects ALTER - used to change the structure of an object DROP - used to delete an object INSERT - used to insert or add new data into a database table UPDATE - used to update or change table data DELETE - used to delete or remove data from a database table SELECT - used to retrieve data stored in database tables COMMIT - used permanently store values used in a transaction into a database table. ROLLBACK - used to reverse changes made to the table data during a transaction GRANT - used to grant permissions to use database objects. For example, you can grant users permissions to view data from a certain table and not others. You can use this command to control who can perform what functions on your database. REVOKE - used to take away granted permissions to perform certain database functions. For example, you granted permissions to user XYZ to delete data from table C. If for some reason, you wish to take away those permissions using the revoke command. |
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