Creating a heirarchy of tables in a schema based on FK

From: Steven Rebello <>
Date: Wed, 18 Nov 2009 13:00:27 +0530
Message-ID: <>

Hi List members

Would like your help/inputs in a problem I am facing here.

I want to clear out records from a huge bunch of selected tables (1000+) which have interdependencies established using FK constraints. Of course, just creating a "delete * from table" doesn't work because of the FK constraints.

What I want to do is to identify the "child" tables which can be deleted first and then create the hierarchy of tables so that the parent tables can then be cleared out, and so on.

Can anyone point me to any reference or script which can generate this hierarchy based on the foreign key constraints? Based on that I can then make the delete script pretty quickly.

I thought of disabling the constraints and re-enabling them after the "delete * from table" script, but would like to try the cleaner approach of starting from the bottom of the dependency tree for these tables.

Steven Rebello
Mastek is in NASSCOM's 'India Top 20' Software Service Exporters List. In the US, we're called MAJESCOMASTEK

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Received on Wed Nov 18 2009 - 01:30:27 CST

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