private RoutingResult doRoute(Select prepare) {
List<TableFilter> filters = filterNotTableMate(prepare.getTopTableFilter());
List<TableFilter> shards = New.arrayList(filters.size());
List<TableFilter> globals = New.arrayList(filters.size());
List<TableFilter> fixeds = New.arrayList(filters.size());
for (TableFilter tf : filters) {
TableMate table = getTableMate(tf);
switch (table.getTableRule().getType()) {
case TableRule.SHARDED_NODE_TABLE:
shards.add(tf);
break;
case TableRule.GLOBAL_NODE_TABLE:
globals.add(tf);
break;
case TableRule.FIXED_NODE_TABLE:
fixeds.add(tf);
break;
default:
break;
}
}
RoutingResult result = null;
if (!shards.isEmpty()) {
for (TableFilter f : shards) {
f.setEvaluatable(f, false);
if (f.isJoinOuter() || f.isJoinOuterIndirect()) {
prepare.getCondition().createIndexConditions(session, f);
}
TableMate table = getTableMate(f);
ConditionExtractor extractor = new ConditionExtractor(f);
RoutingResult r =
routingHandler.doRoute(
table, extractor.getStart(), extractor.getEnd(), extractor.getInColumns());
result = (result == null || r.compareTo(result) < 0) ? r : result;
}
for (TableFilter f : shards) {
f.setEvaluatable(f, true);
}
} else if (!fixeds.isEmpty()) {
for (TableFilter tf : shards) {
TableMate table = getTableMate(tf);
RoutingResult r = routingHandler.doRoute(table);
result = r;
}
} else if (!globals.isEmpty()) {
// 全部为全局表查询，随机取一个第一个表结点
GlobalTableRule tableRule = (GlobalTableRule) getTableRule(globals.iterator().next());
RoutingResult r = tableRule.getRandomRoutingResult();
result = r;
} else {
throw DbException.throwInternalError("SQL_ROUTING_ERROR");
}
ObjectNode[] selectNodes = result.getSelectNodes();
if (selectNodes.length == 0) {
throw DbException.throwInternalError("SQL_ROUTING_ERROR,empty result");
}
setConsistencyTableNodes(selectNodes, filters);
return result;
}
@Override
protected void doPrepare() {
expressions = prepared.getExpressions();
if (prepared.isGroupQuery()) {
ArrayList<Expression> selectExprs = New.arrayList(10);
int[] groupIndex = prepared.getGroupIndex();
for (int i = 0; i < groupIndex.length; i++) {
int idx = groupIndex[i];
Expression expr = expressions.get(idx);
selectExprs.add(expr);
}
HashSet<Aggregate> aggregates = New.hashSet();
for (Expression expr : expressions) {
expr.isEverything(ExpressionVisitor.getAggregateVisitor(aggregates));
}
selectExprs.addAll(aggregates);
expressions = selectExprs;
}
Expression[] exprList = expressions.toArray(new Expression[expressions.size()]);
Integer limit = null, offset = null;
Expression limitExpr = prepared.getLimit();
Expression offsetExpr = prepared.getOffset();
if (limitExpr != null) {
limit = limitExpr.getValue(session).getInt();
}
if (offsetExpr != null) {
offset = offsetExpr.getValue(session).getInt();
}
RoutingResult rr = doRoute(prepared);
if (rr.isMultipleNode() && offset != null) {
if (offset > database.getSettings().analyzeSample) {
throw DbException.get(
ErrorCode.INVALID_VALUE_2,
"offset",
offset
+ ", the max support offset "
+ database.getSettings().analyzeSample
+ " is defined by analyzeSample.");
}
offset = offset != null ? 0 : offset;
}
ObjectNode[] selectNodes = rr.getSelectNodes();
if (session.getDatabase().getSettings().optimizeMerging) {
selectNodes = rr.group();
}
workers = New.arrayList(selectNodes.length);
for (ObjectNode node : selectNodes) {
QueryWorker queryHandler =
queryHandlerFactory.createQueryWorker(
prepared, node, consistencyTableNodes, exprList, limit, offset);
workers.add(queryHandler);
}
}