From 7ff698da2f9e6b2f9fe2cb1e2bbe29c1833caf32 Mon Sep 17 00:00:00 2001
From: Xiang Gu <xiang@cockroachlabs.com>
Date: Thu, 29 Jun 2023 16:08:52 -0400
Subject: [PATCH] sctest: Run backup/restore tests if exactly one database has
 schema changed

We skip backup/restore tests in declarative schema changer if more than
one databases have had schema changes, because we are doing database
level backup. This should not change any existing test case but rather
skip new ones (to be added in the next commit) like
```
create index idx on t (i);
create database db;
```

Release note: None
---
 pkg/sql/schemachanger/sctest/framework.go | 66 ++++++++++++-----------
 1 file changed, 34 insertions(+), 32 deletions(-)

diff --git a/pkg/sql/schemachanger/sctest/framework.go b/pkg/sql/schemachanger/sctest/framework.go
index a66f6ea4467f..cd8e5713bd88 100644
--- a/pkg/sql/schemachanger/sctest/framework.go
+++ b/pkg/sql/schemachanger/sctest/framework.go
@@ -753,40 +753,42 @@ func maybeGetDatabaseForIDs(
 	t *testing.T, tdb *sqlutils.SQLRunner, ids catalog.DescriptorIDSet,
 ) (dbName string, exists bool) {
 	const q = `
-SELECT
-	name
-FROM
-	system.namespace
-WHERE
-	id
-	IN (
-			SELECT
-				DISTINCT
-				COALESCE(
-					d->'database'->>'id',
-					d->'schema'->>'parentId',
-					d->'type'->>'parentId',
-					d->'function'->>'parentId',
-					d->'table'->>'parentId'
-				)::INT8
-			FROM
-				(
-					SELECT
-						crdb_internal.pb_to_json('desc', descriptor) AS d
-					FROM
-						system.descriptor
-					WHERE
-						id IN (SELECT * FROM ROWS FROM (unnest($1::INT8[])))
-				)
-		)
-`
-	err := tdb.DB.QueryRowContext(context.Background(), q, pq.Array(ids.Ordered())).Scan(&dbName)
-	if errors.Is(err, gosql.ErrNoRows) {
+	SELECT
+		name
+	FROM
+		system.namespace
+	WHERE
+		id
+		IN (
+				SELECT
+					DISTINCT
+					COALESCE(
+						d->'database'->>'id',
+						d->'schema'->>'parentId',
+						d->'type'->>'parentId',
+						d->'function'->>'parentId',
+						d->'table'->>'parentId'
+					)::INT8
+				FROM
+					(
+						SELECT
+							crdb_internal.pb_to_json('desc', descriptor) AS d
+						FROM
+							system.descriptor
+						WHERE
+							id IN (SELECT * FROM ROWS FROM (unnest($1::INT8[])))
+					)
+			)
+	`
+	results := tdb.QueryStr(t, q, pq.Array(ids.Ordered()))
+	if len(results) > 1 {
+		skip.IgnoreLintf(t, "requires all schema changes to happen within one database;"+
+			" get %v: %v", len(results), results)
+	}
+	if len(results) == 0 {
 		return "", false
 	}
-
-	require.NoError(t, err)
-	return dbName, true
+	return results[0][0], true
 }
 
 // withPostCommitPlanAfterSchemaChange