PostgreSQL "DESCRIBE TABLE"

Question

How do you perform the equivalent of Oracle's DESCRIBE TABLE in PostgreSQL (using the psql command)?

Answer 1

The psql equivalent of "DESCRIBE TABLE" is "\d table".

See the psql portion of the PostgreSQL manual for more details.

Answer 2

It looks like you can do that with a psql slash command:

 \d table     describe table (or view, index, sequence)

From http://www.faqs.org/docs/ppbook/c4890.htm

Answer 3

Try this:

\d+ tablename

See this link for more info.

Answer 4

In addition to the PostgreSQL way (\d 'something' or \dt 'table' or \ds 'sequence' and so on)

The SQL standard way, as shown here:

select column_name from INFORMATION_SCHEMA.COLUMNS where table_name = 'table';

It's supported by many db engines.

Answer 5

If you want to obtain it from query instead of psql, you can query the catalog schema. Here's a complex query that does that:

SELECT f.attnum AS number, f.attname AS name, f.attnum, f.attnotnull AS notnull, pg_catalog.format_type(f.atttypid,f.atttypmod) AS type, CASE WHEN p.contype = 'p' THEN 't' ELSE 'f' END AS primarykey, CASE WHEN p.contype = 'u' THEN 't' ELSE 'f' END AS uniquekey, CASE WHEN p.contype = 'f' THEN g.relname END AS foreignkey, CASE WHEN p.contype = 'f' THEN p.confkey END AS foreignkey_fieldnum, CASE WHEN p.contype = 'f' THEN g.relname END AS foreignkey, CASE WHEN p.contype = 'f' THEN p.conkey END AS foreignkey_connnum, CASE WHEN f.atthasdef = 't' THEN d.adsrc END AS default FROM pg_attribute f JOIN pg_class c ON c.oid = f.attrelid JOIN pg_type t ON t.oid = f.atttypid LEFT JOIN pg_attrdef d ON d.adrelid = c.oid AND d.adnum = f.attnum LEFT JOIN pg_namespace n ON n.oid = c.relnamespace LEFT JOIN pg_constraint p ON p.conrelid = c.oid AND f.attnum = ANY ( p.conkey ) LEFT JOIN pg_class AS g ON p.confrelid = g.oid WHERE c.relkind = 'r'::char AND n.nspname = '%s' AND c.relname = '%s' AND f.attnum > 0 ORDER BY number;

It's pretty complex but it does show you the power and flexibility of the PostgreSQL system catalog and should get you on your way to pg_catalog mastery ;-). Be sure to change out the %s's in the query. The first is Schema and the second is the table name.