SQL Drop Table.

Using DROP TABLE.

• Beware of that table contents and definition are both gone after a DROP TABLE.
• Before you DROP any table, you should first remove (drop) any constraints related to the table.
  MySQL, PostgreSQL:

  DROP TABLE [ IF EXISTS ] table-name;

  Example:

  DROP TABLE IF EXISTS BOOKSTORE;

  MySQL, PostgreSQL, Oracle, SQL server:

  DROP TABLE  table-name;

  Example:

  DROP TABLE BOOKSTORE;

  Syntax for table existence test in SQL server:

  IF (EXISTS (SELECT table_name  FROM INFORMATION_SCHEMA.TABLES 
                   WHERE TABLE_SCHEMA = 'TheSchema_name' 
                   AND  TABLE_NAME = 'TheTable_name'))
  BEGIN
      DROP TABLE TheTable_name;
  END;

  Example:

  IF (EXISTS (SELECT table_name  FROM INFORMATION_SCHEMA.TABLES 
                   WHERE TABLE_SCHEMA = 'dbo' 
                   AND  TABLE_NAME = 'Customer'))
  BEGIN
      DROP TABLE Customer;
  END;

  Syntax for table existence test in Oracle:

  DECLARE 
   var_count int;
  BEGIN
   SELECT count(*) INTO var_count FROM all_tables WHERE table_name = 'TheTable_name';
   IF var_count > 0 THEN
     EXECUTE IMMEDIATE  'DROP TABLE TheTable_name';
     END IF;
  END;

  Example:

  DECLARE 
   var_count int;
  BEGIN
   SELECT count(*) INTO var_count FROM all_tables WHERE table_name = 'CUSTOMER';
   IF var_count > 0 THEN
     EXECUTE IMMEDIATE  'DROP TABLE CUSTOMER';
     END IF;
  END;