mysql - 在另一个过程中使用 mysql 获取诊断

Question

我想建立一个公共(public)错误日志程序。 mysql 5.7.2 我尝试在同一过程中使用 get 条件，有效。 我记得这种方法以前有效，可能是旧的mysql版本，或者我更改了设置。现在，@errNo、@errMsg 始终为 NULL。

CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_err_log`()
BEGIN
    GET DIAGNOSTICS @cno = NUMBER;
    GET DIAGNOSTICS CONDITION 1 @errNo = MYSQL_ERRNO, @errMsg = MESSAGE_TEXT;
SELECT @errNo, @errMsg;
END

CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_test`()
BEGIN

    DECLARE CONTINUE HANDLER FOR SQLEXCEPTION
    BEGIN 
        CALL sp_err_log();         
    END;

    select 1;
    select * from tbl_not_exist;
    select 2;
END

Answer 1

13.6.7.7 The MySQL Diagnostics Area :: 13.6.7.7.3 How the Diagnostics Area is Populated

...

SQL statements clear and set the diagnostics area as follows:

• When the server starts executing a statement after parsing it, it clears the diagnostics area for nondiagnostic statements that use tables. ...

...

参见db-fiddle .

>= MySQL 5.7.2

13.6.7.7 The MySQL Diagnostics Area :: 13.6.7.7.3 How the Diagnostics Area is Populated

...

SQL statements clear and set the diagnostics area as follows:

• When the server starts executing a statement after parsing it, it clears the diagnostics area for nondiagnostic statements. (Before MySQL 5.7.2, the server clears the diagnostics area for nondiagnostic statements that use tables.) ...

...

参见db-fiddle .

可能的替代解决方案(>= MySQL 5.7.2):

DELIMITER //

CREATE PROCEDURE `sp_err_log`(
  `_MYSQL_ERRNO` INT,
  `_MESSAGE_TEXT` TEXT
)
BEGIN
  SELECT
    `_MYSQL_ERRNO`,
    `_MESSAGE_TEXT`;
END//

CREATE PROCEDURE `sp_test`()
BEGIN
  DECLARE CONTINUE HANDLER FOR SQLEXCEPTION
  BEGIN
    DECLARE
      `_NUMBER`,
      `_MYSQL_ERRNO` INT;
    DECLARE
      `_MESSAGE_TEXT` TEXT;
    GET STACKED DIAGNOSTICS `_NUMBER` = NUMBER;
    GET STACKED DIAGNOSTICS CONDITION `_NUMBER`
      `_MYSQL_ERRNO` = MYSQL_ERRNO,
      `_MESSAGE_TEXT` = MESSAGE_TEXT;
    CALL `sp_err_log`(
      `_MYSQL_ERRNO`,
      `_MESSAGE_TEXT`
    );
  END;
  SELECT 1;
  SELECT NULL
  FROM `tbl_not_exist`;
  SELECT 2;
END//

DELIMITER ;

参见db-fiddle .