DELIMITER $$

USE 'dzhst2'$$

DROP PROCEDURE IF EXISTS `test_mwl`$$

CREATE PROCEDURE `test_mwl`()
BEGIN
DECLARE flag INT DEFAULT 0;
DECLARE v_co VARCHAR(32);
DECLARE v_c10 MEDIUMTEXT;
DECLARE objs LONGTEXT;
-- 定义游标
DECLARE myCursor CURSOR FOR
    (SELECT DISTINCT co,c10 FROM ST22059_main WHERE c10 IS NOT NULL);
DECLARE CONTINUE HANDLER FOR NOT FOUND SET flag=1;
-- 创建临时表
DROP TABLE IF EXISTS tmp_table;   
CREATE TEMPORARY TABLE tmp_table(
tmp_co VARCHAR(32),
tmp_c10 MEDIUMTEXT
)ENGINE=MEMORY;
-- 打开游标
OPEN myCursor;
-- 将游标指定的数据赋值给变量
FETCH myCursor INTO v_co,v_c10;
REPEAT
IF NOT flag THEN 
    INSERT INTO tmp_table(tmp_co,tmp_c10) VALUES(v_co,v_c10);
END IF;
UNTIL flag
END REPEAT;
-- 关闭游标
CLOSE myCursor; 
-- 查询临时表
SET objs='SELECT DISTINCT tmp_co,tmp_c10 FROM tmp_table';
SET @sql_txt = objs;
PREPARE stmt FROM @sql_txt;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
-- 清空临时表
TRUNCATE tmp_table;
END$$

DELIMITER ;