Question

我有大型数据库，每月使用以下查询进行修剪。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，但是最好在纯SQL中将其作为查询直接运行在数据库上。

以noprune为前缀的表（例如noprune_master_tableZ）需要放在循环之外。

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

您实际上只有两个语句，其帮助变量简化为：

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%';

SQL MariaDB-循环查询每个数据库中的每个表，但有例外

1 个答案: