query:
	selects | dml | transaction;

selects:
	select | union ;

dml:
	update | insert;

select:
	SELECT select_item FROM join WHERE where_cond_2 group_by order_by limit;

order_by:
	| ORDER BY field_name;

group_by:
	| GROUP BY field_name;

limit:
	| LIMIT tinyint_unsigned ;

select_item:
	X . field_name | value | COUNT( X . field_name ) | AVG( Y . field_name );

from: 
	table_name AS X | ( select ) AS X;

where_cond_2:
	X . field_name < value;

where_cond_1:
	field_name < value;

insert:
	INSERT INTO table_name ( field_name , field_name ) VALUES ( value , value ) ;

update:
	UPDATE table_name AS X
	SET field_name = value
	WHERE where_cond_2 ORDER BY RAND ( ) limit ;

delete:
	DELETE FROM table_name WHERE where_cond_1 ORDER BY RAND ( ) limit;

join:
	table_name AS X LEFT JOIN table_name AS Y ON ( X . field_name = Y . field_name );

transaction: start | end;

start: START TRANSACTION;

end: COMMIT | ROLLBACK;

union:
	( select ) UNION ALL ( select ) ;

value:
	tinyint_unsigned;

table_name:
	A | B | C | D | E | F ;

field_name:
	'pk' | 'int_key' | 'int_nokey' ;