PG17 regress sanity: fix diffs in multi_router_planner,

multi_router_planner_fast_path and query_single_shard_table

Restore the expected DEBUG error messages from the router planner.
In the case of query_single_shard_table the diffs are because of
PG17's ability to pull up correlated ANY subqueries (*). The fix
is to inhibit pull up with a volatile function.

In the case of multi_router_planner and multi_router_planner_fast_path
the diffs are because of PG17's ability to remove redundant IS (NOT)
NULL expressions (**). The fix is to adjust the table definition so
the column used for distribution is not marked NOT NULL.

(*) https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=9f1337639
(**) https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=b262ad440

src/test/regress/expected/multi_router_planner.out

@@ -10,7 +10,7 @@ CREATE SCHEMA multi_router_planner;
 SET search_path TO multi_router_planner;
 CREATE TABLE articles_hash (
 	id bigint NOT NULL,
-	author_id bigint NOT NULL,
+	author_id bigint,
 	title varchar(20) NOT NULL,
 	word_count integer
 );

src/test/regress/expected/multi_router_planner_fast_path.out

@@ -1157,7 +1157,7 @@ DEBUG:  query has a single distribution column value: 10
 SELECT *
 	FROM articles_hash a
 	WHERE a.author_id is null;
-DEBUG:  Router planner cannot handle multi-shard select queries
+DEBUG:  Creating router plan
  id | author_id | title | word_count
 ---------------------------------------------------------------------
 (0 rows)

src/test/regress/expected/query_single_shard_table.out

@@ -1183,7 +1183,7 @@ DEBUG:  Local tables cannot be used in distributed queries.
 DEBUG:  skipping recursive planning for the subquery since it contains references to outer queries
 ERROR:  direct joins between distributed and local tables are not supported
 SELECT COUNT(*) FROM nullkey_c1_t1 t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM citus_local_table t2 WHERE t2.b = t1.a
 );
 DEBUG:  router planner does not support queries that reference non-colocated distributed tables
@@ -1258,7 +1258,7 @@ DEBUG:  Local tables cannot be used in distributed queries.
 DEBUG:  skipping recursive planning for the subquery since it contains references to outer queries
 ERROR:  direct joins between distributed and local tables are not supported
 SELECT COUNT(*) FROM citus_local_table t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM nullkey_c1_t1 t2 WHERE t2.b = t1.a
 );
 DEBUG:  router planner does not support queries that reference non-colocated distributed tables
@@ -1312,7 +1312,7 @@ DEBUG:  skipping recursive planning for the subquery since it contains reference
 ERROR:  direct joins between distributed and local tables are not supported
 HINT:  Use CTE's or subqueries to select from local tables and use them in joins
 SELECT COUNT(*) FROM nullkey_c1_t1 t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM postgres_local_table t2 WHERE t2.b = t1.a
 );
 DEBUG:  found no worker with all shard placements
@@ -1344,7 +1344,7 @@ DEBUG:  skipping recursive planning for the subquery since it contains reference
 ERROR:  direct joins between distributed and local tables are not supported
 HINT:  Use CTE's or subqueries to select from local tables and use them in joins
 SELECT COUNT(*) FROM postgres_local_table t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM nullkey_c1_t1 t2 WHERE t2.b = t1.a
 );
 DEBUG:  found no worker with all shard placements

src/test/regress/sql/multi_router_planner.sql

@@ -15,7 +15,7 @@ SET search_path TO multi_router_planner;
 
 CREATE TABLE articles_hash (
 	id bigint NOT NULL,
-	author_id bigint NOT NULL,
+	author_id bigint,
 	title varchar(20) NOT NULL,
 	word_count integer
 );

src/test/regress/sql/query_single_shard_table.sql

@@ -502,7 +502,7 @@ WHERE NOT EXISTS (
 );
 
 SELECT COUNT(*) FROM nullkey_c1_t1 t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM citus_local_table t2 WHERE t2.b = t1.a
 );
 
@@ -543,7 +543,7 @@ WHERE EXISTS (
 );
 
 SELECT COUNT(*) FROM citus_local_table t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM nullkey_c1_t1 t2 WHERE t2.b = t1.a
 );
 
@@ -573,7 +573,7 @@ WHERE NOT EXISTS (
 );
 
 SELECT COUNT(*) FROM nullkey_c1_t1 t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM postgres_local_table t2 WHERE t2.b = t1.a
 );
 
@@ -593,7 +593,7 @@ WHERE EXISTS (
 );
 
 SELECT COUNT(*) FROM postgres_local_table t1
-WHERE t1.b IN (
+WHERE t1.b + random() IN (
     SELECT b+1 FROM nullkey_c1_t1 t2 WHERE t2.b = t1.a
 );