Re: COPY ... FROM and index usage

On Nov 4, 2007, at 9:15 AM, Reg Me Please wrote:

> Il Sunday 04 November 2007 14:59:10 Josh Tolley ha scritto:
>> On 11/4/07, Reg Me Please <regmeplease(at)gmail(dot)com> wrote:
>>> Hi all.
>>>
>>> I'd like to know whether the indexes on a table are updated or
>>> not during
>>> a "COPY ... FROM" request.
>>>
>>> That is, should I drop all indexes during a "COPY ... FROM" in
>>> order to
>>> gain the maximum speed to load data?
>>>
>>> Thanks.
>>
>> Although questions of "which is faster" often depend very heavily on
>> the data involved, the database schema, the hardware, etc., typically
>> people find it best to drop all indexes during a large import and
>> recreate them afterward.
>>
>> - Josh/eggyknap
>
> This sounds very reasonable to me.
> But the first question remains unanswered:
>
> Are the indexes updated during the COPY ... FROM ?

Of course. Why would think that data could be inserted into a table
by any means without it updating the table's indexes? That would
make the index worthless.

Erik Jones

Software Developer | Emma®
erik(at)myemma(dot)com
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