public Void visit(SqlCall call) {
final SqlOperator operator = call.getOperator();
if (operator.isAggregator()) {
throw new Util.FoundOne(call);
}
// User-defined function may not be resolved yet.
if (operator instanceof SqlFunction
&& ((SqlFunction) operator).getFunctionType()
== SqlFunctionCategory.USER_DEFINED_FUNCTION) {
final List<SqlOperator> list = Lists.newArrayList();
opTab.lookupOperatorOverloads(
((SqlFunction) operator).getSqlIdentifier(),
SqlFunctionCategory.USER_DEFINED_FUNCTION,
SqlSyntax.FUNCTION,
list);
for (SqlOperator sqlOperator : list) {
if (sqlOperator.isAggregator()) {
throw new Util.FoundOne(call);
}
}
}
if (call.isA(SqlKind.QUERY)) {
// don't traverse into queries
return null;
}
if (call.getKind() == SqlKind.OVER) {
if (over) {
throw new Util.FoundOne(call);
} else {
// an aggregate function over a window is not an aggregate!
return null;
}
}
return super.visit(call);
}
/**
* Constructs a FarragoReentrantSubquery.
*
* @param subq the subquery to evaluate
* @param parentConverter sqlToRelConverter associated with the parent query
* @param isExists whether the subquery is part of an EXISTS expression
* @param isExplain whether the subquery is part of an EXPLAIN PLAN statement
* @param results the resulting evaluated expressions
*/
FarragoReentrantSubquery(
SqlCall subq,
SqlToRelConverter parentConverter,
boolean isExists,
boolean isExplain,
List<RexNode> results) {
super(
FennelRelUtil.getPreparingStmt(parentConverter.getCluster()).getRootStmtContext(),
parentConverter.getRexBuilder(),
results);
FarragoSessionStmtContext rootContext = getRootStmtContext();
if (rootContext != null) {
rootContext.setSaveFirstTxnCsn();
}
if (!isExists) {
assert subq.getKind() == SqlKind.SCALAR_QUERY;
}
this.subq = subq;
this.parentConverter = parentConverter;
this.isExists = isExists;
this.isExplain = isExplain;
}