Thread: SELECT INTO TEMPORARY problem
I have a servlet which gets its data through a DataSource (Tomcat 5.5) and starts each request as a new SQL transaction and either commits the transaction or rolls it back at the end of each request. In one of the requests I do a SELECT ... INTO TEMPORARY t1 ..., which works just fine when I first use it, but from then on it objects saying that t1 already exists. When I read the documentation (8.1 as that is what I am using) I thought I understood that the table would disappear at the end of the transaction. Other than deleting it, is there something else I need to do or have I missunderstood that into temporary does? David
David Goodenough <david.goodenough@btconnect.com> writes:
> In one of the requests I do a SELECT ... INTO TEMPORARY t1 ..., which
> works just fine when I first use it, but from then on it objects saying
> that t1 already exists. When I read the documentation (8.1 as that is
> what I am using) I thought I understood that the table would disappear
> at the end of the transaction.
No, the default is to last until end of session.
There's an ON COMMIT DROP option in the CREATE TEMP TABLE syntax,
but I don't think it's possible to stick it into an INTO TEMP clause.
regards, tom lane
David Goodenough wrote: > I thought I understood that the table would disappear > at the end of the transaction. Other than deleting it, is there something > else I need to do or have I missunderstood that into temporary does? Dropped when the connection is closed normally, but see the ON COMMIT. http://www.postgresql.org/docs/8.1/static/sql-createtable.html You might have to do CREATE TABLE then INSERT INTO ... SELECT though. -- Richard Huxton Archonet Ltd
am Wed, dem 17.01.2007, um 16:04:10 +0000 mailte David Goodenough folgendes: > I have a servlet which gets its data through a DataSource (Tomcat 5.5) > and starts each request as a new SQL transaction and either commits > the transaction or rolls it back at the end of each request. > > In one of the requests I do a SELECT ... INTO TEMPORARY t1 ..., which > works just fine when I first use it, but from then on it objects saying > that t1 already exists. When I read the documentation (8.1 as that is > what I am using) I thought I understood that the table would disappear > at the end of the transaction. Other than deleting it, is there something > else I need to do or have I missunderstood that into temporary does? known problem, FAQ. Use EXECUTE for your DDL-Statements. http://www.postgresql.org/docs/faqs.FAQ.html#item4.19 Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
On 1/17/07, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> David Goodenough <david.goodenough@btconnect.com> writes:
> > In one of the requests I do a SELECT ... INTO TEMPORARY t1 ..., which
> > works just fine when I first use it, but from then on it objects saying
> > that t1 already exists. When I read the documentation (8.1 as that is
> > what I am using) I thought I understood that the table would disappear
> > at the end of the transaction.
>
> No, the default is to last until end of session.
>
> There's an ON COMMIT DROP option in the CREATE TEMP TABLE syntax,
> but I don't think it's possible to stick it into an INTO TEMP clause.
>
> regards, tom lane
>
IIRC, you can do it using CREATE TEMP TABLE t1 ON COMMIT DROP AS query
but i think this new in 8.2
why not extending this to SELECT INTO TEMP?
--
regards,
Jaime Casanova
"Programming today is a race between software engineers striving to
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So far, the universe is winning."
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