Merge #145567

145567: scbuildstmt: remove fallback for DROP DATABASE with MR system database r=rafiss a=rafiss

This fallback was only needed before we implemeted the region liveness changes.

Epic: None
Release note: None

Co-authored-by: Rafi Shamim <[email protected]>

Author: craig[bot]

pkg/bench/rttanalysis/testdata/benchmark_expectations

@@ -35,10 +35,10 @@ exp,benchmark
 14,"Discard/DISCARD_ALL,_1_tables_in_1_db"
 19,"Discard/DISCARD_ALL,_2_tables_in_2_dbs"
 0,"Discard/DISCARD_ALL,_no_tables"
-17,DropDatabase/drop_database_0_tables
-18,DropDatabase/drop_database_1_table
-18,DropDatabase/drop_database_2_tables
-18,DropDatabase/drop_database_3_tables
+15,DropDatabase/drop_database_0_tables
+16,DropDatabase/drop_database_1_table
+16,DropDatabase/drop_database_2_tables
+16,DropDatabase/drop_database_3_tables
 29-30,DropRole/drop_1_role
 37,DropRole/drop_2_roles
 45-49,DropRole/drop_3_roles

pkg/sql/schemachanger/scbuild/internal/scbuildstmt/drop_database.go

@@ -6,20 +6,16 @@
 package scbuildstmt
 
 import (
-	"github.com/cockroachdb/cockroach/pkg/keys"
 	"github.com/cockroachdb/cockroach/pkg/sql/pgwire/pgcode"
 	"github.com/cockroachdb/cockroach/pkg/sql/pgwire/pgerror"
 	"github.com/cockroachdb/cockroach/pkg/sql/privilege"
-	"github.com/cockroachdb/cockroach/pkg/sql/schemachanger/scerrors"
 	"github.com/cockroachdb/cockroach/pkg/sql/schemachanger/scpb"
 	"github.com/cockroachdb/cockroach/pkg/sql/sem/catid"
 	"github.com/cockroachdb/cockroach/pkg/sql/sem/tree"
 )
 
 // DropDatabase implements DROP DATABASE.
 func DropDatabase(b BuildCtx, n *tree.DropDatabase) {
-	fallBackIfMRSystemDatabase(b, n)
-
 	elts := b.ResolveDatabase(n.Name, ResolveParams{
 		IsExistenceOptional: n.IfExists,
 		RequiredPrivilege:   privilege.DROP,
@@ -67,11 +63,3 @@ func DropDatabase(b BuildCtx, n *tree.DropDatabase) {
 	panic(pgerror.DangerousStatementf(
 		"DROP DATABASE on non-empty database without explicit CASCADE"))
 }
-
-func fallBackIfMRSystemDatabase(b BuildCtx, t *tree.DropDatabase) {
-	// TODO(jeffswenson): delete once region_livess is implemented (#107966)
-	_, _, dbRegionConfig := scpb.FindDatabaseRegionConfig(b.QueryByID(keys.SystemDatabaseID))
-	if dbRegionConfig != nil {
-		panic(scerrors.NotImplementedErrorf(t, "drop database not implemented when the system database is multi-region"))
-	}
-}