黑洞引擎的创造性用途 [英] Creative uses for the blackhole engine

问题描述

根据文档:
http://dev.mysql.com/doc/refman/5.0/zh-CN/blackhole-storage-engine.html

According to the documentation:
http://dev.mysql.com/doc/refman/5.0/en/blackhole-storage-engine.html

黑洞存储引擎可用于诊断和将二进制日志卸载到另一台计算机上，而无需将数据库存储在该计算机上.

the blackhole storage engine can be used for things like diagnostics and offloading the binary log to a different machine, without having to store the database on that machine.

您还能为该引擎使用什么其他广告?

What other creative uses for this engine can you come up with?

推荐答案

使用触发器找到了一个:

Found one a using a trigger:

如果您需要在事务中进行一系列复杂的插入或更新操作，则可以在应用程序代码中完成这些操作，或者

If you have a complicated series of inserts or updates that needs to happen in a transaction, you can do these in application code, or

您可以创建一个具有足够多行以容纳所有值的大" blackhole表.

You can create one 'big' blackhole table with enough rows to hold all the values.

并创建一个触发器，例如:

And create a trigger like:

DELIMITER $$

CREATE TRIGGER ai_bh_table_each AFTER INSERT ON bh_table FOR EACH ROW
BEGIN
  DECLARE lastid1 integer;

  INSERT INTO table1 VALUES (null, new.field1, new.field2);
  SELECT LAST_INSERT_ID() INTO lastid1;
  INSERT INTO table2 VALUES (null, new.field3, lastid1);
  ....  
END$$

DELIMITER ;

如果包含错误检查代码，您甚至可以在不支持它的引擎(例如MyISAM)上模拟事务.

If you include error checking code you can even simulate transactions on engines that don't support it, like MyISAM.

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