Message-ID: <6fff7b00a759e89f6468757602ac752c8d4ffdfc.camel@cybertec.at>
Subject: Re: Adding Column on Huge Table
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Moin Akther <moindba@hotmail.com>, "pgsql-admin@lists.postgresql.org"
	 <pgsql-admin@lists.postgresql.org>
Date: Tue, 19 Mar 2019 18:02:19 +0100
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Organization: Cybertec
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Moin Akther wrote:
> We want to add a column on table size of 1.5TB, we have to perform this activity with minimal downtime. 
> 
> What are the best practises to add a column on huge table ?
> 
> How much time alter statement will take to add column ?
> 
> Any alternate solution other than alter statement to add column ?
> 
> Will adding a new column on a huge table generate huge WAL files ?

As a quick experiment would have told you, adding a column without a DEFAULT
clause is very fast.  Since v11, it is fast even if the new column has a
DEFAULT clause.

Yours,
Laurenz Albe
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