Rearrange core regression tests to reduce cross-script dependencies.

The idea behind this patch is to make it possible to run individual
test scripts without running the entire core test suite.  Making all
the scripts completely independent would involve a massive rewrite,
and would probably be worse for coverage of things like concurrent DDL.
So this patch just does what seems practical with limited changes.

The net effect is that any test script can be run after running
limited earlier dependencies:
* all scripts depend on test_setup
* many scripts depend on create_index
* other dependencies are few in number, and are documented in
  the parallel_schedule file.

To accomplish this, I chose a small number of commonly-used tables
and moved their creation and filling into test_setup.  Later scripts
are expected not to modify these tables' data contents, for fear of
affecting other scripts' results.  Also, our former habit of declaring
all C functions in one place is now gone in favor of declaring them
where they're used, if that's just one script, or in test_setup if
necessary.

There's more that could be done to remove some of the remaining
inter-script dependencies, but significantly more-invasive changes
would be needed, and at least for now it doesn't seem worth it.

Discussion: https://postgr.es/m/1114748.1640383217@sss.pgh.pa.us

1 files changed, 0 insertions, 27 deletions

diff --git a/src/test/regress/sql/insert.sql b/src/test/regress/sql/insert.sql
index bfaa8a3b27..bdcffd0314 100644
--- a/src/test/regress/sql/insert.sql
+++ b/src/test/regress/sql/insert.sql
@@ -250,33 +250,6 @@ select tableoid::regclass::text, a, min(b) as min_b, max(b) as max_b from list_p
 
 -- direct partition inserts should check hash partition bound constraint
 
--- Use hand-rolled hash functions and operator classes to get predictable
--- result on different machines.  The hash function for int4 simply returns
--- the sum of the values passed to it and the one for text returns the length
--- of the non-empty string value passed to it or 0.
-
-create or replace function part_hashint4_noop(value int4, seed int8)
-returns int8 as $$
-select value + seed;
-$$ language sql immutable;
-
-create operator class part_test_int4_ops
-for type int4
-using hash as
-operator 1 =,
-function 2 part_hashint4_noop(int4, int8);
-
-create or replace function part_hashtext_length(value text, seed int8)
-RETURNS int8 AS $$
-select length(coalesce(value, ''))::int8
-$$ language sql immutable;
-
-create operator class part_test_text_ops
-for type text
-using hash as
-operator 1 =,
-function 2 part_hashtext_length(text, int8);
-
 create table hash_parted (
 	a int
 ) partition by hash (a part_test_int4_ops);