MySQL 8.0 Query Rewrite支持DML

MySQL 8.0 Query Rewrite支持SELECT INSERT UPDETE DELETE REPLACE語句重寫

這個功能要點贊，比如開發上線時，有個SQL查詢字段索引忘記加了，直接把線上CPU打滿，此時，你可以將SQL重寫，讓業務先報錯，別打死數據庫，然后馬上通知開發回滾，等加完索引后再上線。

安裝插件

mysql?-S?/tmp/mysql_hcy.sock?-p123456?<./install_rewriter.sql

查看是否生效

SHOW?GLOBAL?VARIABLES?LIKE?'rewriter_enabled';

編寫重寫規則

insert?into?query_rewrite.rewrite_rules(pattern,?replacement,?
pattern_database)?values?(
"SELECT?*?from?sbtest1?limit??",
"SELECT?k,c?from?sbtest1?limit??",
"test");

意思為：

將以下語句

SELECT * from sbtest1 limit ?;

改寫成：

SELECT k,c from sbtest1 limit ?;

注：問號?為變量

執行規則生效

CALL?query_rewrite.flush_rewrite_rules();

演示

mysql>?SELECT?*?from?sbtest1?limit?1\G;
***************************?1.?row?***************************
k:?499284
c:?83868641912-28773972837-60736120486-75162659906-27563526494-20381887404-41576422241-93426793964-56405065102-33518432330
1?row?in?set,?1?warning?(0.00?sec)
?
ERROR:?
No?query?specified
?
mysql>?show?warnings\G
***************************?1.?row?***************************
??Level:?Note
???Code:?1105
Message:?Query?'SELECT?*?from?sbtest1?limit?1'?rewritten?to?'SELECT?k,c?from?sbtest1?limit?1'?by?a?query?rewrite?plugin
1?row?in?set?(0.00?sec)