Re: Res: Finding all tables that have foreign keys referencing a table - Mailing list pgsql-sql

On Friday 07 November 2008 15:15:49 paulo matadr wrote:
> Try this
>
> select table_schema, table_name
> from information_schema.columns
> where table_schema not in
> ('information_schema','pg_catalog')
> and column_name = '?'

AFAICS this lists all tables which have a column named '?', which is not what I'm after. I'm after listing all columns
referencinga certain column as a FOREIGN KEY. 

Example, making the FK's names "$1" to mimic old PG-behaviour, and proving my point about the FK-names not needing to
beglobaly unique: 

CREATE TABLE test1(
id INTEGER PRIMARY KEY
);

CREATE TABLE test2(
id INTEGER PRIMARY KEY
);

CREATE TABLE test_ref1(
id INTEGER PRIMARY KEY,
entity_id INTEGER,
CONSTRAINT "$1" FOREIGN KEY (entity_id) REFERENCES test1(id)
);

CREATE TABLE test_ref2(
id INTEGER PRIMARY KEY,
entity_id INTEGER,
CONSTRAINT "$1" FOREIGN KEY (entity_id) REFERENCES test2(id)
);

andreak=# \d test_ref1   Table "public.test_ref1" Column   |  Type   | Modifiers
-----------+---------+-----------id        | integer | not nullentity_id | integer |
Indexes:   "test_ref1_pkey" PRIMARY KEY, btree (id)
Foreign-key constraints:   "$1" FOREIGN KEY (entity_id) REFERENCES test1(id)

andreak=# \d test_ref2   Table "public.test_ref2" Column   |  Type   | Modifiers
-----------+---------+-----------id        | integer | not nullentity_id | integer |
Indexes:   "test_ref2_pkey" PRIMARY KEY, btree (id)
Foreign-key constraints:   "$1" FOREIGN KEY (entity_id) REFERENCES test2(id)

andreak=#

Now, any idea about how to safely get all columns which reference test1.id?
-hackers; Any hints?

BTW:
andreak=# select version();                                           version
-----------------------------------------------------------------------------------------------PostgreSQL 8.3.3 on
i486-pc-linux-gnu,compiled by GCC cc (GCC) 4.2.3 (Ubuntu 4.2.3-2ubuntu7) 

--
Andreas Joseph Krogh <andreak@officenet.no>
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