Thread

1. query column def

   Peter Harvey <pharvey@codebydesign.com> — 2001-08-21T18:49:54Z

   Hi;
   
   I am reverse engineering a PostgreSQL database by querying catalog
   tables. I have run into a problem where I can not determine the exact
   info used in i.e. the CREATE TABLE statement. For example; how to
   determine the exact precision/length and scale used in a NUMERIC(p,s)
   column def.
   
   Looking at the PostgreSQL ODBC driver I see that it does some funky
   stuff such as reporting VARCHAR(maxlen) instead of i.e. VARCHAR(50) or
   whatever the column def was. So it appears that the author had similar
   problems. The result is that the ODBC driver does not appear to be
   absolutely accurate.
   
   Is this information availible somewhere in the catalog tables?
   
   Peter
   
   
   
   
   

2. Re: query column def

   Tom Lane <tgl@sss.pgh.pa.us> — 2001-08-21T19:22:59Z

   Peter Harvey <pharvey@codebydesign.com> writes:
   > Is this information availible somewhere in the catalog tables?
   
   Yes, in the atttypmod column of pg_attribute.
   
   I'd recommend looking at psql's \d commands (describe.c), or at
   pg_dump, to see the approved way to retrieve catalog info.  Those
   are kept up to date pretty faithfully, whereas other interfaces
   aren't necessarily.  (Feel free to submit a patch to fix ODBC...)
   
   			regards, tom lane