Hi all,
I'm sure it's a FAQ, and I discovered syscat.source, but was still not
able to determine how to get a table description in a query.
I want my code to be able to get column names and column types.
Thanks.
--
Stand Fast,
tjg.
Timothy Grant
www.craigelachie.org
Timothy Grant wrote:
> Hi all,
>
> I'm sure it's a FAQ, and I discovered syscat.source, but was still not
> able to determine how to get a table description in a query.
>
Start psql with "-E" on the command line. Then you see all the internally
generated queries. This is using cvs, but it works in prior versions also:
$ psql -E regression
********* QUERY **********
BEGIN; SELECT usesuper FROM pg_catalog.pg_user WHERE usename = 'postgres'; COMMIT
**************************
Welcome to psql 7.4devel, the PostgreSQL interactive terminal.
Type: \copyright for distribution terms
\h for help with SQL commands
\? for help on internal slash commands
\g or terminate with semicolon to execute query
\q to quit
regression=# \d foo
********* QUERY **********
SELECT c.oid,
n.nspname,
c.relname
FROM pg_catalog.pg_class c
LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE pg_catalog.pg_table_is_visible(c.oid)
AND c.relname ~ '^foo$'
ORDER BY 2, 3;
**************************
********* QUERY **********
SELECT relhasindex, relkind, relchecks, reltriggers, relhasrules
FROM pg_catalog.pg_class WHERE oid = '822242'
**************************
********* QUERY **********
SELECT a.attname,
pg_catalog.format_type(a.atttypid, a.atttypmod),
a.attnotnull, a.atthasdef, a.attnum
FROM pg_catalog.pg_attribute a
WHERE a.attrelid = '822242' AND a.attnum > 0 AND NOT a.attisdropped
ORDER BY a.attnum
**************************
********* QUERY **********
SELECT c2.relname, i.indisprimary, i.indisunique,
pg_catalog.pg_get_indexdef(i.indexrelid)
FROM pg_catalog.pg_class c, pg_catalog.pg_class c2, pg_catalog.pg_index i
WHERE c.oid = '822242' AND c.oid = i.indrelid AND i.indexrelid = c2.oid
ORDER BY i.indisprimary DESC, i.indisunique DESC, c2.relname
**************************
Table "public.foo"
Column | Type | Modifiers
--------+---------+-----------
f1 | integer | not null
f2 | text | not null
f3 | text[] |
Indexes: foo_pkey primary key btree (f1, f2)
HTH,
Joe
Joe,
Thank you so very much! That is gonna be hugely helpful!
Wow! Slightly more involved queries than I expected! Anyway that's a
huge help.
On Mon, 2002-12-02 at 19:44, Joe Conway wrote:
> Timothy Grant wrote:
> > Hi all,
> >
> > I'm sure it's a FAQ, and I discovered syscat.source, but was still not
> > able to determine how to get a table description in a query.
> >
>
> Start psql with "-E" on the command line. Then you see all the internally
> generated queries. This is using cvs, but it works in prior versions also:
>
> $ psql -E regression
> ********* QUERY **********
> BEGIN; SELECT usesuper FROM pg_catalog.pg_user WHERE usename = 'postgres'; COMMIT
> **************************
>
> Welcome to psql 7.4devel, the PostgreSQL interactive terminal.
>
> Type: \copyright for distribution terms
> \h for help with SQL commands
> \? for help on internal slash commands
> \g or terminate with semicolon to execute query
> \q to quit
>
> regression=# \d foo
> ********* QUERY **********
> SELECT c.oid,
> n.nspname,
> c.relname
> FROM pg_catalog.pg_class c
> LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
> WHERE pg_catalog.pg_table_is_visible(c.oid)
> AND c.relname ~ '^foo$'
> ORDER BY 2, 3;
> **************************
>
> ********* QUERY **********
> SELECT relhasindex, relkind, relchecks, reltriggers, relhasrules
> FROM pg_catalog.pg_class WHERE oid = '822242'
> **************************
>
> ********* QUERY **********
> SELECT a.attname,
> pg_catalog.format_type(a.atttypid, a.atttypmod),
> a.attnotnull, a.atthasdef, a.attnum
> FROM pg_catalog.pg_attribute a
> WHERE a.attrelid = '822242' AND a.attnum > 0 AND NOT a.attisdropped
> ORDER BY a.attnum
> **************************
>
> ********* QUERY **********
> SELECT c2.relname, i.indisprimary, i.indisunique,
> pg_catalog.pg_get_indexdef(i.indexrelid)
> FROM pg_catalog.pg_class c, pg_catalog.pg_class c2, pg_catalog.pg_index i
> WHERE c.oid = '822242' AND c.oid = i.indrelid AND i.indexrelid = c2.oid
> ORDER BY i.indisprimary DESC, i.indisunique DESC, c2.relname
> **************************
>
> Table "public.foo"
> Column | Type | Modifiers
> --------+---------+-----------
> f1 | integer | not null
> f2 | text | not null
> f3 | text[] |
> Indexes: foo_pkey primary key btree (f1, f2)
>
>
> HTH,
>
> Joe
>
>
>
>
--
Stand Fast,
tjg.
Timothy Grant
www.craigelachie.org
