Re: [SQL] Getting datatype before SELECT

Thus spake Glenn Sullivan
> In my C code which communicates with the Postgres database,
> I have the need to determine the datatype of a column, before
> I have done a SELECT command.  I have the name of the column,
> but I cannot seem to figure out how to get the datatype information
> until after I have done a SELECT.  Then I can call  PQfnumber() and
> PQftype() to get the type.  Does anyone know how to do this?

Here's a select statement I use to get the types of a class.

SELECT pg_attribute.attname, pg_type.typname
        FROM pg_class, pg_attribute, pg_type
        WHERE pg_class.relname = '%s' AND
            pg_attribute.attnum > 0 AND
            pg_attribute.attrelid = pg_class.oid AND
            pg_attribute.atttypid = pg_type.oid

The "%s" gets replaced by the class name and the typname shows the
name of the type.  Here's an example output.

attname  |typname
---------+-------
ride_id  |int4
name     |text
from_date|date
to_date  |date
contact  |text
phone    |text
email    |text
url      |text
(8 rows)

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