SET @rownum:= 30 ;
SET @cid:= 0 ;
SET @count:= 0 ;
SELECT @count:=COUNT(*) FROM my_table;

SET @count:=@count-@rownum;
SET @count:=IF (@count>= 0 ,@count, 0 );

CREATE TEMPORARY TABLE zz(row_id INTEGER, id INTEGER);
INSERT INTO zz SELECT @cid:=@cid+ 1 , t1.id FROM my_table t1;

SELECT * FROM zz WHERE zz.row_id>@count ORDER BY zz.id;

 -- Вместо
 
SELECT * FROM zz WHERE zz.row_id>@count ORDER BY zz.id;

SELECT t1.* FROM zz LEFT JOIN My_Table t1 ON zz.id=t1.id
WHERE zz.row_id>@count ORDER BY zz.id;