使用折半查找法删除

DELIMITER //
DROP PROCEDURE IF EXISTS `PRO_BinarySearch_DeleteData` ;
CREATE PROCEDURE PRO_BinarySearch_DeleteData(IN p_tab VARCHAR(50),IN p_key1  VARCHAR(30), IN p_key2 VARCHAR(30),IN p_date DATETIME)
BEGIN
/*折半查找最大主键ID*/
/*Auther:Gerald*/
SET @v_str =
CONCAT('select 
    max(',p_key1,') into @v_maxid 
from 
    ',p_tab);
    
PREPARE stmt FROM @v_str;
EXECUTE stmt;


SET @v_str=
CONCAT('SELECT 
    min(',p_key1,') INTO @v_minid 
FROM 
    ',p_tab);

PREPARE stmt FROM @v_str;
EXECUTE stmt;

SELECT UNIX_TIMESTAMP(p_date) INTO @v_date;

SET @v_id=@v_minid;
WHILE @v_minid<=@v_maxid DO 
    SELECT CEIL((@v_minid+@v_maxid)/2) INTO @v_midid;
    SET @v_str =CONCAT('select ',p_key2,' into @v_created_at from ',p_tab,' where ',p_key1,'>=@v_midid order by 1 limit 1');
    
    PREPARE stmt FROM @v_str;
    EXECUTE stmt;
    

    /*right*/
    IF @v_created_at<=@v_date THEN 
    SET @v_minid=@v_midid+1;
    END IF;
    
    /*left*/
    IF @v_created_at>=@v_date THEN
    SET @v_maxid=@v_midid-1;
    END IF;
END WHILE;

/*分批次删除历史数据*/
SET @rowcnt=0;
START TRANSACTION;
cursor_loop:LOOP
    set @v_str =CONCAT('DELETE FROM ',p_tab,' WHERE ',p_key1,'=',@v_id);
    PREPARE stmt FROM @v_str;
    EXECUTE stmt;
    
    SET @rowcnt=@rowcnt+1;
    IF @rowcnt=1000 THEN
        SET @rowcnt =0 ;
        COMMIT;
        START TRANSACTION;
    END IF ;
    SET @v_id=@v_id+1;
    IF @v_id > @v_midid THEN
        LEAVE cursor_loop ;
    END IF ;
END LOOP cursor_loop ;
COMMIT ;

SELECT @v_midid;
END;
//


DELIMITER  ;