[GRASS5] Trouble with d.what.v.pg

GRASS GRASS developer
1

I'm trying to run d.what.v.pg in 5.0.2 CVS head in the command line mode. It fails with an error if I select a text column from the database.

Executing
SELECT * from POLBNDA_area where nam=8222
--------------------
Error: select Postgres:ERROR: Unable to identify an operator '=' for types 'text' and 'integer'
You will have to retype this query using an explicit cast

If I select a numeric column, I get no error but also get no results: it returns "0 rows selected". It looks like buildPg.c is assigning the category value from dig_cats to the variable that is supposed to hold the search results. Does anyone know how this is supposed to work?

2

I'm trying to run d.what.v.pg in 5.0.2 CVS head in the command line mode.
It fails with an error if I select a text column from the database.

Executing
SELECT * from POLBNDA_area where nam=8222
--------------------
Error: select Postgres:ERROR: Unable to identify an operator '=' for types
'text' and 'integer'
You will have to retype this query using an explicit cast

If I select a numeric column, I get no error but also get no results: it
returns "0 rows selected". It looks like buildPg.c is assigning the
category value from dig_cats to the variable that is supposed to hold the
search results. Does anyone know how this is supposed to work?

If nam is text, the condition in the query should be: nam='8222'

Moritz

3

------ Original Message -----
From: "Moritz Lennert" <mlennert@club.worldonline.be>
To: "Chris Heg" <cheg01@attbi.com>
Cc: "grass5 developers list" <grass5@grass.itc.it>
Sent: Monday, March 10, 2003 1:15 AM
Subject: Re: [GRASS5] Trouble with d.what.v.pg

> I'm trying to run d.what.v.pg in 5.0.2 CVS head in the command line

mode.

> It fails with an error if I select a text column from the database.
>
>
> Executing
> SELECT * from POLBNDA_area where nam=8222
> --------------------
> Error: select Postgres:ERROR: Unable to identify an operator '=' for

types

> 'text' and 'integer'
> You will have to retype this query using an explicit cast
>
>
>
> If I select a numeric column, I get no error but also get no results: it
> returns "0 rows selected". It looks like buildPg.c is assigning the
> category value from dig_cats to the variable that is supposed to hold

the

> search results. Does anyone know how this is supposed to work?

If nam is text, the condition in the query should be: nam='8222'

Moritz

But I don't know apriori what the value of nam is, the SQL querey is
supposer to extract that information from the database. I don't understand
how assigning the cat number to the query field name can work.I don't know
much about SQL, but it seems to me I need "find the value of 'nam' for the
record where 'id=8222'. It would require a mapping between a known column in
the database and the value stored in dig_cats.