Partition drop first

src/backend/distributed/metadata/node_metadata.c

@@ -811,12 +811,6 @@ SyncDistributedObjectsCommandList(WorkerNode *workerNode)
 	 */
 	commandList = list_concat(commandList, PropagateNodeWideObjectsCommandList());
 
-	commandList = lappend(commandList, BREAK_CITUS_TABLE_SEQUENCE_DEPENDENCY_COMMAND);
-
-	/* first remove partitioned tables to avoid any need for detaching partitions */
-	commandList = lappend(commandList, REMOVE_PARTITIONED_SHELL_TABLES_COMMAND);
-	commandList = lappend(commandList, REMOVE_ALL_SHELL_TABLES_COMMAND);
-
 	/*
 	 * Replicate all objects of the pg_dist_object to the remote node.
 	 */
@@ -1127,7 +1121,8 @@ PrimaryNodeForGroup(int32 groupId, bool *groupContainsNodes)
 
 	return NULL;
 }
-
+static void
+DropExistingMetadataInOutsideTransaction(List *nodeList);
 
 /*
  * ActivateNodeList iterates over the nodeList and activates the nodes.
@@ -1174,6 +1169,34 @@ ActivateNodeList(List *nodeList)
 		/* both nodes should be the same */
 		Assert(workerNode->nodeId == node->nodeId);
 
+		workerNode =
+			SetWorkerColumnLocalOnly(workerNode, Anum_pg_dist_node_isactive,
+									 BoolGetDatum(true));
+
+		/* TODO: Once all tests will be enabled for MX, we can remove sync by default check */
+		bool syncMetadata = EnableMetadataSync && NodeIsPrimary(workerNode);
+		if (syncMetadata)
+		{
+			nodeToSyncMetadata = lappend(nodeToSyncMetadata, workerNode);
+		}
+	}
+
+	/*
+	 * Before we do any remote commands for syncing the metadata,
+	 * we can first drop any existing metadata, just in case we are
+	 * re-syncing the metadata to a node.
+	 *
+	 * Note that we send these commands in an outside transaction
+	 * because in certain cases drop commands generate excessive
+	 * amount of relcache invalidation events, and sending those
+	 * commands in the main transaction that we sync the metadata
+	 * becomes problematic.
+	 */
+	DropExistingMetadataInOutsideTransaction(nodeToSyncMetadata);
+
+	WorkerNode *workerNode = NULL;
+	foreach_ptr(workerNode, nodeToSyncMetadata)
+	{
 		/*
 		 * Delete existing reference and replicated table placements on the
 		 * given groupId if the group has been disabled earlier (e.g., isActive
@@ -1190,14 +1213,6 @@ ActivateNodeList(List *nodeList)
 															localOnly);
 		}
 
-		workerNode =
-			SetWorkerColumnLocalOnly(workerNode, Anum_pg_dist_node_isactive,
-									 BoolGetDatum(true));
-
-		/* TODO: Once all tests will be enabled for MX, we can remove sync by default check */
-		bool syncMetadata = EnableMetadataSync && NodeIsPrimary(workerNode);
-		if (syncMetadata)
-		{
 		/*
 		 * We are going to sync the metadata anyway in this transaction, so do
 		 * not fail just because the current metadata is not synced.
@@ -1211,8 +1226,6 @@ ActivateNodeList(List *nodeList)
 		 */
 		UpdateLocalGroupIdOnNode(workerNode);
 
-			nodeToSyncMetadata = lappend(nodeToSyncMetadata, workerNode);
-		}
 	}
 
 	/*
@@ -1249,6 +1262,36 @@ ActivateNodeList(List *nodeList)
 }
 
 
+static void
+DropExistingMetadataInOutsideTransaction(List *nodeList)
+{
+	List *connectionList = NIL;
+
+	WorkerNode *workerNode = NULL;
+	foreach_ptr(workerNode, nodeList)
+	{
+		int connectionFlags = FORCE_NEW_CONNECTION;
+
+		Assert (superuser());
+		MultiConnection *connection =
+			GetNodeUserDatabaseConnection(connectionFlags, workerNode->workerName,
+										  workerNode->workerPort, NULL, NULL);
+
+		connectionList = lappend(connectionList, connection);
+	}
+
+
+	ExecuteRemoteCommandInConnectionList(connectionList, BREAK_CITUS_TABLE_SEQUENCE_DEPENDENCY_COMMAND);
+
+	ExecuteRemoteCommandInConnectionList(connectionList, REMOVE_PARTITIONED_SHELL_TABLES_COMMAND);
+	ExecuteRemoteCommandInConnectionList(connectionList, REMOVE_ALL_SHELL_TABLES_COMMAND);
+
+	MultiConnection *connection;
+	foreach_ptr(connection, connectionList)
+		CloseConnection(connection);
+}
+
+
 /*
  * ActivateNode activates the node with nodeName and nodePort. Currently, activation
  * includes only replicating the reference tables and setting isactive column of the

src/backend/distributed/worker/worker_drop_protocol.c

@@ -189,6 +189,8 @@ WorkerDropDistributedTable(Oid relationId)
 								PROCESS_UTILITY_QUERY, NULL, None_Receiver, NULL);
 	}
 }
+
+
 #include "access/xact.h"
 
 /*