Thread: index auto changes after copying data ?

index auto changes after copying data ?

From
"energumen@buaa.edu.cn"
Date:
I know in mysql, index will auto change after copying data
Of course, index will change after inserting a line in postgresql, but what about copying data?


Re: index auto changes after copying data ?

From
Richard Huxton
Date:
energumen@buaa.edu.cn wrote:
> I know in mysql, index will auto change after copying data
> Of course, index will change after inserting a line in postgresql, but what about copying data?

The index will (of course) know about the new data.
You might want to ANALYZE the table again after a large copy in case the
statistics about how many different values are present changes.

--
  Richard Huxton
  Archonet Ltd

Re: index auto changes after copying data ?

From
Chris Browne
Date:
energumen@buaa.edu.cn ("energumen@buaa.edu.cn") writes:
> I know in mysql, index will auto change after copying data Of
> course, index will change after inserting a line in postgresql, but
> what about copying data?

Do you mean, by this, something like...

"Are indexes affected by loading data using the COPY command just as
they are if data is loaded using INSERT?"

If so, then the answer is "Yes, certainly."  Indexes are updated
whichever statement you use to load in data.
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