2 files changed, 24 insertions, 13 deletions

diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
index 5f68cc13776..2c9cea58269 100644
--- a/src/backend/catalog/namespace.c
+++ b/src/backend/catalog/namespace.c
@@ -3215,7 +3215,7 @@ isOtherTempNamespace(Oid namespaceId)
 }
 
 /*
- * isTempNamespaceInUse - is the given namespace owned and actively used
+ * checkTempNamespaceStatus - is the given namespace owned and actively used
  * by a backend?
  *
  * Note: this can be used while scanning relations in pg_class to detect
@@ -3223,8 +3223,8 @@ isOtherTempNamespace(Oid namespaceId)
  * given database.  The result may be out of date quickly, so the caller
  * must be careful how to handle this information.
  */
-bool
-isTempNamespaceInUse(Oid namespaceId)
+TempNamespaceStatus
+checkTempNamespaceStatus(Oid namespaceId)
 {
 	PGPROC	   *proc;
 	int			backendId;
@@ -3233,25 +3233,35 @@ isTempNamespaceInUse(Oid namespaceId)
 
 	backendId = GetTempNamespaceBackendId(namespaceId);
 
-	/* No such temporary namespace? */
+	/* No such namespace, or its name shows it's not temp? */
 	if (backendId == InvalidBackendId)
-		return false;
+		return TEMP_NAMESPACE_NOT_TEMP;
 
 	/* Is the backend alive? */
 	proc = BackendIdGetProc(backendId);
 	if (proc == NULL)
-		return false;
+		return TEMP_NAMESPACE_IDLE;
 
 	/* Is the backend connected to the same database we are looking at? */
 	if (proc->databaseId != MyDatabaseId)
-		return false;
+		return TEMP_NAMESPACE_IDLE;
 
 	/* Does the backend own the temporary namespace? */
 	if (proc->tempNamespaceId != namespaceId)
-		return false;
+		return TEMP_NAMESPACE_IDLE;
 
-	/* all good to go */
-	return true;
+	/* Yup, so namespace is busy */
+	return TEMP_NAMESPACE_IN_USE;
+}
+
+/*
+ * isTempNamespaceInUse - oversimplified, deprecated version of
+ * checkTempNamespaceStatus
+ */
+bool
+isTempNamespaceInUse(Oid namespaceId)
+{
+	return checkTempNamespaceStatus(namespaceId) == TEMP_NAMESPACE_IN_USE;
 }
 
 /*
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 2d925d2ee0c..ac0242c9d37 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -2089,9 +2089,10 @@ do_autovacuum(void)
 		{
 			/*
 			 * We just ignore it if the owning backend is still active and
-			 * using the temporary schema.
+			 * using the temporary schema.  Also, for safety, ignore it if the
+			 * namespace doesn't exist or isn't a temp namespace after all.
 			 */
-			if (!isTempNamespaceInUse(classForm->relnamespace))
+			if (checkTempNamespaceStatus(classForm->relnamespace) == TEMP_NAMESPACE_IDLE)
 			{
 				/*
 				 * The table seems to be orphaned -- although it might be that
@@ -2261,7 +2262,7 @@ do_autovacuum(void)
 			continue;
 		}
 
-		if (isTempNamespaceInUse(classForm->relnamespace))
+		if (checkTempNamespaceStatus(classForm->relnamespace) != TEMP_NAMESPACE_IDLE)
 		{
 			UnlockRelationOid(relid, AccessExclusiveLock);
 			continue;