30 lines
1.3 KiB
SQL
30 lines
1.3 KiB
SQL
|
-- Pre-clean for `restore cluster --empty`. A pg_dumpall stream recreates roles
|
||
|
|
-- and databases, so replaying it into a populated cluster dies on the first
|
||
|
|
-- CREATE ROLE. Emitted as one DROP per row and run via \gexec so each executes
|
||
|
|
-- as its own top-level statement: DROP DATABASE cannot run inside a
|
||
|
|
-- transaction block, which rules out a single DO block.
|
||
|
|
-- The phase column pins the order: databases must be gone before their owners
|
||
|
|
-- can be dropped, and DROP OWNED BY releases what a role still holds in the
|
||
|
|
-- control database. Template databases, the control database itself, the pg_*
|
||
|
|
-- system roles and the connecting role are kept - the dump does not recreate
|
||
|
|
-- them and dropping them would end the session.
|
||
|
|
SELECT statement
|
||
|
|
FROM (
|
||
|
|
SELECT 1 AS phase,
|
||
|
|
format('DROP DATABASE IF EXISTS %I', datname) AS statement
|
||
|
|
FROM pg_database
|
||
|
|
WHERE NOT datistemplate
|
||
|
|
AND datname <> current_database()
|
||
|
|
UNION ALL
|
||
|
|
SELECT 2, format('DROP OWNED BY %I', rolname)
|
||
|
|
FROM pg_roles
|
||
|
|
WHERE NOT starts_with(rolname, 'pg_')
|
||
|
|
AND rolname <> current_user
|
||
|
|
UNION ALL
|
||
|
|
SELECT 3, format('DROP ROLE IF EXISTS %I', rolname)
|
||
|
|
FROM pg_roles
|
||
|
|
WHERE NOT starts_with(rolname, 'pg_')
|
||
|
|
AND rolname <> current_user
|
||
|
|
) drops
|
||
|
|
ORDER BY phase
|
||
|
|
\gexec
|