Truncate table tool

[kevinburke1]

One thing I frequently want/need to do is truncate a test database. Generally this is something along the lines of

BEGIN 
SET CONSTRAINTS ALL DEFERRED
DELETE FROM <>;
DELETE FROM <>;
COMMIT;

It would be nice to be able to get a list of tables out in order to run this query.

(My initial thought was sqlc should build a dependency graph to delete the tables in the right order and then realized we don't need to do that because you can defer constraint enforcement to the end.)

[kevinburke1]

Related, I am needing to add info about the pg_tables or information_schema tables in order to get sqlc to compile a query to list all of the tables.

[kevinburke1]

Ahhh, right, I do need the dependency graph because foreign keys are not deferrable by default so I need to go back and make them all deferrable or delete the tables in the "correct" order which in theory sqlc could infer.

[kyleconroy]

I'm working on adding support for all the pg_* tables from the system catalog here #1171.