Re: [SPAM?]: Re: Support for REINDEX CONCURRENTLY

On 10 December 2012 22:27, Peter Eisentraut <peter_e@gmx.net> wrote:
> On 12/10/12 5:21 PM, Simon Riggs wrote:
>> On 10 December 2012 22:18, Peter Eisentraut <peter_e@gmx.net> wrote:
>>> On 12/8/12 9:40 AM, Tom Lane wrote:
>>>> I'm tempted to propose that REINDEX CONCURRENTLY simply not try to
>>>> preserve the index name exactly.  Something like adding or removing
>>>> trailing underscores would probably serve to generate a nonconflicting
>>>> name that's not too unsightly.
>>>
>>> If you think you can rename an index without an exclusive lock, then why
>>> not rename it back to the original name when you're done?
>>
>> Because the index isn't being renamed. An alternate equivalent index
>> is being created instead.
>
> Right, basically, you can do this right now using
>
> CREATE INDEX CONCURRENTLY ${name}_tmp ...
> DROP INDEX CONCURRENTLY ${name};
> ALTER INDEX ${name}_tmp RENAME TO ${name};
>
> The only tricks here are if ${name}_tmp is already taken, in which case
> you might as well just error out (or try a few different names), and if
> ${name} is already in use by the time you get to the last line, in which
> case you can log a warning or an error.
>
> What am I missing?

That this is already recorded in my book> ;-)

And also that REINDEX CONCURRENTLY doesn't work like that, yet.

-- Simon Riggs                   http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services