mysql - SQL MariaDB - 对每个数据库中的每个表循环此查询，但有异常(exception)

Question

我有一个大型数据库，我使用下面的查询每月对其进行修剪。但是，我有数百个表，并且希望将其放入数据库中每个表的 foreach 循环中。

我知道如何在 PHP 中实现此循环，但如果能在纯 SQL 中直接作为数据库查询运行，那就太好了。

以 noprune 为前缀的表(例如 noprune_master_tableZ)需要排除在循环之外。

我从哪里开始？谢谢

START TRANSACTION;
set @N := (now());
CREATE TABLE master_tableA_snapshot AS SELECT * FROM master_tableA where insertDATE < date_sub(@N,INTERVAL 32 DAY);
SELECT * from master_tableA_snapshot INTO OUTFILE '/tmp/master_tableA_snapshot_TODAYSDATE.csv' FIELDS TERMINATED BY ',' ENCLOSED BY '"' LINES TERMINATED BY '\n';
DELETE from master_tableA where insertDATE < date_sub(@N,INTERVAL 32 DAY);
DROP TABLE master_tableA_snapshot;
COMMIT;

Answer 1

您实际上只有两个带有辅助变量的语句，简化为:

set @N := date_sub(NOW(),INTERVAL 32 DAY);

SELECT *
FROM master_tableA
WHERE insertDATE < @N
INTO OUTFILE '/tmp/master_tableA_snapshot_TODAYSDATE.csv'
FIELDS TERMINATED BY ',' ENCLOSED BY '"' LINES TERMINATED BY '\n';

DELETE from master_tableA where insertDATE < @N;

PHP 通过查询选择表名:

SELECT TABLE_NAME
FROM information_schema.TABLES
WHERE SCHEMA='mydatabase'
  AND TABLE_NAME NOT LIKE 'noprune%';