What causes " find no Route:" in MyCATApache/Mycat-Server?

Include the sharding/partition column in the WHERE clause so a datanode can be selected

MyCATApache/Mycat-Server · error · SQLNonTransientException

find no Route:

Error message

 find no Route:

What it means

DruidSelectParser, after evaluating all routing conditions for a SELECT (sharding keys, global tables, broadcast rules), found an empty nodeSet — no datanode matches the query. It throws SQLNonTransientException ' find no Route:' followed by the SQL text.

Solutions

Include the sharding/partition column in the WHERE clause so a datanode can be selected
Mark the table as global in schema.xml if it is a small lookup table broadcast to all nodes
Review the sharding rule in rule.xml to ensure the queried value maps to a node
If full-table scans are intended, configure the table/route strategy to broadcast to all datanodes

Example fix

// before
SELECT * FROM orders;
// after (orders sharded by customer_id)
SELECT * FROM orders WHERE customer_id = 123;

Defensive patterns

Strategy: validation

Validate before calling

if (!whereContainsShardingColumn(sql, table)) log.warn("query on sharded table without sharding column may fail routing: " + table);

Try / catch

try { query(sql); } catch (SQLNonTransientException e) { if (e.getMessage().startsWith(" find no Route:")) { fallbackToBroadcastOrReject(e); } else throw e; }

Prevention

Always filter sharded tables by their sharding key
Mark lookup tables as global in schema.xml
Test routing for all query patterns in the app
Catch the error and fall back to a fan-out query only when full scans are acceptable

When it happens

Trigger: DruidSelectParser routing a SELECT where no WHERE-condition on the sharding column, ER join, or global-table rule yields any RouteResultsetNode — typically a query with no usable sharding condition on a non-global sharded table that has no broadcast fallback configured.

Common situations: SELECT on a sharded table without including the sharding column in WHERE; sharding rule misconfigured so no node matches; join conditions not recognized by MyCat's ER analysis; global table flag missing so cross-node queries can't resolve.

Understand the failure class

Background: EmptyResultError / "no results found": when an API or scraper succeeds but returns zero rows — this error's family across 9 libraries.

Related errors

AI-assisted analysis of MyCATApache/Mycat-Server@65f8d8beb7 (2026-09-11). Data as JSON: /api/errors/ca11d0a3eb7b1228. Report an issue: GitHub.

Appendix: source

Thrown at src/main/java/io/mycat/route/parser/druid/impl/DruidSelectParser.java:618

				for(String key: ctx.getTableAliasMap().keySet()){
					TableConfig tb_config = schema.getTables().get(key.toUpperCase());
					if(tb_config!=null){
						String table_name = ctx.getTableAliasMap().get(key);
						for(String dataNode:tb_config.getDataNodes()){
							if(tb_config.getDataNodes().size()==1 || table_name.startsWith(dataNode+'.')){
								rrs = RouterUtil.routeToSingleNode(rrs, dataNode, ctx.getSql());
								rrs.setFinishedRoute(true);
								return;
							}
						}
					}
				}
			}
			//end@byron

			String msg = " find no Route:" + ctx.getSql();
			LOGGER.warn(msg);
			throw new SQLNonTransientException(msg);
		}

		RouteResultsetNode[] nodes = new RouteResultsetNode[nodeSet.size()];
		int i = 0;
		for (Iterator<RouteResultsetNode> iterator = nodeSet.iterator(); iterator.hasNext();) {
			nodes[i] = (RouteResultsetNode) iterator.next();
			i++;

		}

		rrs.setNodes(nodes);
		rrs.setFinishedRoute(true);
	}


	protected String getCurentDbType()
	{
		return JdbcConstants.MYSQL.name();

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