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Postsdbo
PO
 

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  1. PO
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    <p>Not sure why you are trying to do this at the app layer. MySQL provides the ability to delete child rows using foreign key constraints (ON DELETE CASCADE). Check your current schema and see if they are already available: </p> <pre><code>mysql&gt; show create table child_table; </code></pre> <p>If there is a foreign key constraint available you should see something like:</p> <pre><code>CONSTRAINT `constraint_id` FOREIGN KEY (`some_id`) REFERENCES `some_table` (`id`) ON DELETE CASCADE </code></pre> <p>What this means is if you delete a row from 'some_table', any rows in 'child_table' which reference the same id as 'some_table' will automatically be deleted.</p> <p><a href="http://dev.mysql.com/doc/refman/5.6/en/innodb-foreign-key-constraints.html" rel="nofollow">http://dev.mysql.com/doc/refman/5.6/en/innodb-foreign-key-constraints.html</a> for more info.</p> <p>If you need to do this at the app layer then you should really consider a transaction, I am assuming you are using PDO, although it may work with mysqli. Below is a potential solution, as such I assume no responsibility for any data loss you may incur. </p> <pre><code>$this-&gt;db-&gt;beginTransaction(); try { $this-&gt;db-&gt;execute('DELETE FROM table_1 WHERE id = 65'); $this-&gt;db-&gt;execute('DELETE FROM table_2 WHERE rela = 65'); $this-&gt;db-&gt;execute('DELETE FROM table_3 WHERE h_id = 11'); $this-&gt;db-&gt;execute('DELETE FROM table_4 WHERE rela = 65'); $this-&gt;db-&gt;execute('DELETE FROM table_5 WHERE h_id = 11'); $this-&gt;db-&gt;commit(); } catch (Exception $e) { error_log($e-&gt;getMessage()); $this-&gt;db-&gt;rollBack(); $e = null; // PHP is notorious for not cleaning exceptions very well so force it } </code></pre>
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    1. POSQL DELETE with JOIN
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    1. USMike Purcell
    1. USMike Purcell
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    1. COIn other tables there is not row id, Some of them are `h_id` and some other are `rela`, values their in table row are different. please see my update in first post.
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      1. USJimBo
    2. CODid you check to see if there are already any existing FK constraints?
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      1. USMike Purcell
    3. COI don't understand your mean"already any existing FK constraints"?
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      1. USJimBo
 

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