复现方式：

Delete FROM user Where User='test' and Host='%';

flush privileges;

修复流程：

1.用root用户删除两个函数，语句分别为

DROP FUNCTION IF EXISTS currval;

DROP FUNCTION IF EXISTS nextval;

2.然后用程序用户(sharding_slave)创建函数，创建语句为：

DELIMITER $

CREATE FUNCTION currval (seq_name VARCHAR(50))

RETURNS BIGINT(20)

LANGUAGE SQL

DETERMINISTIC

CONTAINS SQL

SQL SECURITY DEFINER

COMMENT ''

BEGIN

DECLARE value BIGINT(20);

SET value = 0;

SELECT current_value INTO value

FROM key_sequence

WHERE table_name = seq_name;

RETURN value;

END

$

DELIMITER ;

DELIMITER $

CREATE FUNCTION nextval (seq_name VARCHAR(50))

RETURNS BIGINT(20)

LANGUAGE SQL

DETERMINISTIC

CONTAINS SQL

SQL SECURITY DEFINER

COMMENT ''

BEGIN

UPDATE key_sequence

SET current_value = current_value + increment

WHERE table_name = seq_name;

RETURN currval(seq_name);

END

$

DELIMITER ;

3.查看definer 是否为 程序用户

select db,name,type,created,definer from mysql.proc where db like 'dbname;

修改definer:

参考博客：https://www.cnblogs.com/zejin2008/p/4767531.html