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mysql:finding_and_deleting_orphaned_rows

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mysql:finding_and_deleting_orphaned_rows [2016/07/19 13:30] – created petermysql:finding_and_deleting_orphaned_rows [2020/07/15 09:30] (current) – external edit 127.0.0.1
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 The treatment of child rows with a NULL parent_id will vary depending on the requirements of your application, but in general I do not count NULL values as orphans. Thus in my queries above I explicitly check that **child.rental_id** is not NULL. The treatment of child rows with a NULL parent_id will vary depending on the requirements of your application, but in general I do not count NULL values as orphans. Thus in my queries above I explicitly check that **child.rental_id** is not NULL.
-What not to do+ 
 + 
 +===== What not to do =====
  
 I’ve also seen people write queries like the following to find orphaned rows.  In general this will be slower, especially if you are running an older version of MySQL, so I do not recommend this method: I’ve also seen people write queries like the following to find orphaned rows.  In general this will be slower, especially if you are running an older version of MySQL, so I do not recommend this method:
mysql/finding_and_deleting_orphaned_rows.1468935007.txt.gz · Last modified: 2020/07/15 09:30 (external edit)
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