Exemplo n.º 1
0
/*
 * GetPlacementConnection establishes a connection for a placement.
 *
 * See StartPlacementConnection for details.
 */
MultiConnection *
GetPlacementConnection(uint32 flags, ShardPlacement *placement, const char *userName)
{
	MultiConnection *connection = StartPlacementConnection(flags, placement, userName);

	FinishConnectionEstablishment(connection);
	return connection;
}
Exemplo n.º 2
0
/*
 * OpenTransactionsToAllShardPlacements opens connections to all placements
 * using the provided shard identifier list and returns it as a shard ID ->
 * ShardConnections hash. connectionFlags can be used to specify whether
 * the command is FOR_DML or FOR_DDL.
 */
HTAB *
OpenTransactionsToAllShardPlacements(List *shardIntervalList, int connectionFlags)
{
	HTAB *shardConnectionHash = NULL;
	ListCell *shardIntervalCell = NULL;
	List *newConnectionList = NIL;

	shardConnectionHash = CreateShardConnectionHash(CurrentMemoryContext);

	/* open connections to shards which don't have connections yet */
	foreach(shardIntervalCell, shardIntervalList)
	{
		ShardInterval *shardInterval = (ShardInterval *) lfirst(shardIntervalCell);
		uint64 shardId = shardInterval->shardId;
		ShardConnections *shardConnections = NULL;
		bool shardConnectionsFound = false;
		List *shardPlacementList = NIL;
		ListCell *placementCell = NULL;

		shardConnections = GetShardHashConnections(shardConnectionHash, shardId,
												   &shardConnectionsFound);
		if (shardConnectionsFound)
		{
			continue;
		}

		shardPlacementList = FinalizedShardPlacementList(shardId);
		if (shardPlacementList == NIL)
		{
			/* going to have to have some placements to do any work */
			ereport(ERROR, (errmsg("could not find any shard placements for the shard "
								   UINT64_FORMAT, shardId)));
		}

		foreach(placementCell, shardPlacementList)
		{
			ShardPlacement *shardPlacement = (ShardPlacement *) lfirst(placementCell);
			MultiConnection *connection = NULL;

			WorkerNode *workerNode = FindWorkerNode(shardPlacement->nodeName,
													shardPlacement->nodePort);
			if (workerNode == NULL)
			{
				ereport(ERROR, (errmsg("could not find worker node %s:%d",
									   shardPlacement->nodeName,
									   shardPlacement->nodePort)));
			}

			connection = StartPlacementConnection(connectionFlags,
												  shardPlacement,
												  NULL);

			ClaimConnectionExclusively(connection);

			shardConnections->connectionList = lappend(shardConnections->connectionList,
													   connection);

			newConnectionList = lappend(newConnectionList, connection);

			/*
			 * Every individual failure should cause entire distributed
			 * transaction to fail.
			 */
			MarkRemoteTransactionCritical(connection);
		}