MySql代码: 1241 operand should contain 1 column(s)

Question

我在 stackoverflow 中发现了与 Mysql 错误:1241 相关的不同主题。当我阅读所有主题时，他们有一些与其子查询相关的常见问题。但我的问题不同。

问题: - MySql 代码:1241 操作数应包含 1 列

来自 - 我的一个带有准备好的语句的存储过程

注意 - 我的 select 语句和我的 update 语句一样没有子查询。

屏幕截图 -ACTUAL SS

存储过程代码

CREATE PROCEDURE CancelRow_EM(IN tbl_name VARCHAR(25), IN rowindex FLOAT, OUT flagresult TINYINT, OUT msgresult VARCHAR(300))

 BEGIN
 START TRANSACTION;
IF tbl_name="emps_tbl" THEN
    SET @PrimaryCol="EMPS_ID";
    SET @RefCol="OBR NO.";

ELSEIF tbl_name="emmooe_tbl" THEN
    SET @PrimaryCol="EMMOOE_ID";
    SET @RefCol="PR NO.";

ELSEIF tbl_name="emco_tbl" THEN
    SET @PrimaryCol="EMCO_ID";
    SET @RefCol="PR NO.";

END IF;

SET @select1=CONCAT("SELECT `LINK_ID`,`",@RefCol,"` INTO @li,@Ref FROM `",tbl_name,"` WHERE ROUND(`EMPS_ID`,3)=",rowindex);
PREPARE stmtselect1 FROM @select1;
EXECUTE stmtselect1;
DEALLOCATE PREPARE stmtselect1; 

If @li IS NOT NULL THEN
    SET flagresult=0;
    SET msgresult="Cancellation of record was stopped. Reason: Earmark record was already utilize.";

ELSE
    SET @update1=CONCAT("UPDATE `",tbl_name,"` SET `CANCEL_STATUS`=1 WHERE ROUND(`",@PrimaryCol,"`,3)=",rowindex," AND `",@RefCol,"`='",@Ref,"'");
    PREPARE stmtupdate1 FROM @update1;
    EXECUTE stmtupdate1;

    SELECT row_count() INTO @RowsAffected1;
    DEALLOCATE PREPARE stmtupdate1;

    IF @RowsAffected1>0 THEN
        SET flagresult=1;
        SET msgresult=("No. of affected rows(s):",@RowsAffected1,", from modification process.");
        COMMIT;
    ELSE
        SET flagresult=0;
        SET msgresult=("There are no affected row(s) from modification process.");
        ROLLBACK;   
    END IF;
END IF;

END

Answer 1

您不能将元组分配给单个变量。

这个:

SET msgresult=("No. of affected rows(s):",@RowsAffected1,", from modification process.");

应该是:

SET msgresult=CONCAT("No. of affected rows(s):",@RowsAffected1,", from modification process.");