This code drops all tables in the currently selected MySQL database.

Drop-All-Tables.sql

SET FOREIGN_KEY_CHECKS   = 0;
SET GROUP_CONCAT_MAX_LEN = 32768;
SET @tables              = NULL;

SELECT GROUP_CONCAT('`', table_name, '`')   INTO @tables
  FROM information_schema.tables
  WHERE table_schema = (SELECT DATABASE());
SELECT IFNULL(@tables,'dummy')              INTO @tables;

SET @tables = CONCAT('DROP TABLE IF EXISTS ', @tables);
PREPARE stmt FROM @tables;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
SET FOREIGN_KEY_CHECKS = 1;