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Effective way to update a column to null (based on a condition) quickly in a huge 800 GB table [message #629225]

Thu, 04 December 2014 12:21

orausern
Messages: 826
Registered: December 2005

Senior Member

Hi,

I have a huge 800 GB table and need to quickly set a CLOB column of that table - which is taking up all that space to null. Now there is a criteria for this update - only based on a condition I have to set it null. Like if the length of that column is more than x bytes then set it to null. The question is that : if I do a simple UPDATE, for that CLOB column and which will affect about 600 GB, can that space be effectively reused for new inserts updates in that same table? I am guessing yes - because since setting that column to null means space is available in that table so it should be able to be reused , but I would like to know about the opinion on it.

Thanks,

OrauserN

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