Tsearch2: casting text to tsquery

On Wed, 16 Nov 2005, Alexander Presber wrote:

Hello,

I have a question that arose while using tsearch on a large database of book
information.

In order to inject unstemmed + stemmed versions of searchstrings into a query
we want to cast an expression of type text to tsquery.
Unfortunately

SELECT 'word'::tsquery

(where the literal 'word' is of type 'unknown' seemingly) works just fine
while e.g.

SELECT ('word' || '&fullword')::tsquery

or, simpler

SELECT 'word&fullword'::text::tsquery

gives

ERROR: cannot cast type text to tsearch2.tsquery

How can we work around that? Thanks for any help

no workaround needed. to_tsquery provides everything you need. If you
want fancy-shmancy solution you could always write wrapper around tsquery, but
I doubt you enter queries by hand, so why do you bothering ?

Sincerely yours
Alexander Presber

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Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

Am 16.11.2005 um 13:52 schrieb Oleg Bartunov:

On Wed, 16 Nov 2005, Alexander Presber wrote:

Hello,

I have a question that arose while using tsearch on a large
database of book information.

In order to inject unstemmed + stemmed versions of searchstrings
into a query we want to cast an expression of type text to tsquery.
Unfortunately

SELECT 'word'::tsquery

(where the literal 'word' is of type 'unknown' seemingly) works
just fine while e.g.

SELECT ('word' || '&fullword')::tsquery

or, simpler

SELECT 'word&fullword'::text::tsquery

gives

ERROR: cannot cast type text to tsearch2.tsquery

How can we work around that? Thanks for any help

no workaround needed. to_tsquery provides everything you need. If
you want fancy-shmancy solution you could always write wrapper
around tsquery, but
I doubt you enter queries by hand, so why do you bothering ?

No. No fancy-shmancy solution needed, just one that works.

I do not see a way to include both a stemmed and unstemmed version of
a string into a tsquery.
Can you give an example, please?

Thanks
Alex

P.S. I have read the documentation (twice.)

On Wed, 16 Nov 2005, Alexander Presber wrote:

Am 16.11.2005 um 13:52 schrieb Oleg Bartunov:

On Wed, 16 Nov 2005, Alexander Presber wrote:

Hello,

I have a question that arose while using tsearch on a large database of
book information.

In order to inject unstemmed + stemmed versions of searchstrings into a
query we want to cast an expression of type text to tsquery.
Unfortunately

SELECT 'word'::tsquery

(where the literal 'word' is of type 'unknown' seemingly) works just fine
while e.g.

SELECT ('word' || '&fullword')::tsquery

or, simpler

SELECT 'word&fullword'::text::tsquery

gives

ERROR: cannot cast type text to tsearch2.tsquery

How can we work around that? Thanks for any help

no workaround needed. to_tsquery provides everything you need. If you want
fancy-shmancy solution you could always write wrapper around tsquery, but
I doubt you enter queries by hand, so why do you bothering ?

No. No fancy-shmancy solution needed, just one that works.

I do not see a way to include both a stemmed and unstemmed version of a
string into a tsquery.
Can you give an example, please?

This is quite different question and Teodor has already answered you -
use different configurations. But I'm wondering why do you need that.

Thanks
Alex

P.S. I have read the documentation (twice.)

Sincerely yours
Alexander Presber

---------------------------(end of broadcast)---------------------------
TIP 6: explain analyze is your friend

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

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Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83