/** Populates baseTblSmap_ with our combined inline view smap and creates baseTblResultExprs. */
protected void resolveInlineViewRefs(Analyzer analyzer) {
// Gather the inline view substitution maps from the enclosed inline views
for (TableRef tblRef : tableRefs_) {
if (tblRef instanceof InlineViewRef) {
InlineViewRef inlineViewRef = (InlineViewRef) tblRef;
baseTblSmap_ = Expr.SubstitutionMap.combine(baseTblSmap_, inlineViewRef.getBaseTblSmap());
}
}
baseTblResultExprs_ = Expr.cloneList(resultExprs_, baseTblSmap_);
LOG.trace("baseTblSmap_: " + baseTblSmap_.debugString());
LOG.trace("resultExprs: " + Expr.debugString(resultExprs_));
LOG.trace("baseTblResultExprs: " + Expr.debugString(baseTblResultExprs_));
}
/**
* This select block might contain inline views. Substitute all exprs (result of the analysis) of
* this select block referencing any of our inlined views, including everything registered with
* the analyzer. Expressions created during parsing (such as whereClause) are not touched.
*/
protected void substituteInlineViewExprs(Analyzer analyzer) {
// Gather the inline view substitution maps from the enclosed inline views
Expr.SubstitutionMap sMap = new Expr.SubstitutionMap();
for (TableRef tblRef : tableRefs) {
if (tblRef instanceof InlineViewRef) {
InlineViewRef inlineViewRef = (InlineViewRef) tblRef;
sMap = Expr.SubstitutionMap.combine(sMap, inlineViewRef.getExprSMap());
}
}
// we might not have anything to substitute
if (sMap.lhs.size() == 0) {
return;
}
// Substitute select list, join clause, where clause, aggregate, order by
// and this select block's analyzer expressions
// select
Expr.substituteList(resultExprs, sMap);
// aggregation (group by and aggregation expr)
if (aggInfo != null) {
aggInfo.substitute(sMap);
}
// having
if (havingPred != null) {
havingPred.substitute(sMap);
}
// ordering
if (sortInfo != null) {
sortInfo.substitute(sMap);
}
// expressions registered inside the analyzer
analyzer.substitute(sMap);
}
/**
* Analyze aggregation-relevant components of the select block (Group By clause, select list,
* Order By clause), substitute AVG with SUM/COUNT, create the AggregationInfo, including the agg
* output tuple, and transform all post-agg exprs given AggregationInfo's smap.
*
* @param analyzer
* @throws AnalysisException
*/
private void analyzeAggregation(Analyzer analyzer) throws AnalysisException, InternalException {
if (groupingExprs == null
&& !selectList.isDistinct()
&& !Expr.contains(resultExprs, AggregateExpr.class)) {
// we're not computing aggregates
return;
}
// If we're computing an aggregate, we must have a FROM clause.
if (tableRefs.size() == 0) {
throw new AnalysisException("aggregation without a FROM clause is not allowed");
}
if ((groupingExprs != null || Expr.contains(resultExprs, AggregateExpr.class))
&& selectList.isDistinct()) {
throw new AnalysisException(
"cannot combine SELECT DISTINCT with aggregate functions or GROUP BY");
}
// disallow '*' and explicit GROUP BY (we can't group by '*', and if you need to
// name all star-expanded cols in the group by clause you might as well do it
// in the select list)
if (groupingExprs != null) {
for (SelectListItem item : selectList.getItems()) {
if (item.isStar()) {
throw new AnalysisException(
"cannot combine '*' in select list with GROUP BY: " + item.toSql());
}
}
}
// analyze grouping exprs
ArrayList<Expr> groupingExprsCopy = Lists.newArrayList();
if (groupingExprs != null) {
// make a deep copy here, we don't want to modify the original
// exprs during analysis (in case we need to print them later)
groupingExprsCopy = Expr.cloneList(groupingExprs, null);
substituteOrdinals(groupingExprsCopy, "GROUP BY");
Expr ambiguousAlias = getFirstAmbiguousAlias(groupingExprsCopy);
if (ambiguousAlias != null) {
throw new AnalysisException(
"Column " + ambiguousAlias.toSql() + " in group by clause is ambiguous");
}
Expr.substituteList(groupingExprsCopy, aliasSMap);
for (int i = 0; i < groupingExprsCopy.size(); ++i) {
groupingExprsCopy.get(i).analyze(analyzer);
if (groupingExprsCopy.get(i).contains(AggregateExpr.class)) {
// reference the original expr in the error msg
throw new AnalysisException(
"GROUP BY expression must not contain aggregate functions: "
+ groupingExprs.get(i).toSql());
}
}
}
// analyze having clause
if (havingClause != null) {
// substitute aliases in place (ordinals not allowed in having clause)
havingPred = havingClause.clone(aliasSMap);
havingPred.analyze(analyzer);
havingPred.checkReturnsBool("HAVING clause", true);
analyzer.registerConjuncts(havingPred, null, false);
}
List<Expr> orderingExprs = null;
if (sortInfo != null) {
orderingExprs = sortInfo.getOrderingExprs();
}
ArrayList<AggregateExpr> aggExprs = collectAggExprs();
Expr.SubstitutionMap avgSMap = createAvgSMap(aggExprs, analyzer);
// substitute AVG before constructing AggregateInfo
Expr.substituteList(aggExprs, avgSMap);
ArrayList<AggregateExpr> nonAvgAggExprs = Lists.newArrayList();
Expr.collectList(aggExprs, AggregateExpr.class, nonAvgAggExprs);
aggExprs = nonAvgAggExprs;
createAggInfo(groupingExprsCopy, aggExprs, analyzer);
// combine avg smap with the one that produces the final agg output
AggregateInfo finalAggInfo =
aggInfo.getSecondPhaseDistinctAggInfo() != null
? aggInfo.getSecondPhaseDistinctAggInfo()
: aggInfo;
Expr.SubstitutionMap combinedSMap =
Expr.SubstitutionMap.combine(avgSMap, finalAggInfo.getSMap());
LOG.debug("combined smap: " + combinedSMap.debugString());
// change select list, having and ordering exprs to point to agg output
Expr.substituteList(resultExprs, combinedSMap);
LOG.debug("post-agg selectListExprs: " + Expr.debugString(resultExprs));
if (havingPred != null) {
havingPred = havingPred.substitute(combinedSMap);
LOG.debug("post-agg havingPred: " + havingPred.debugString());
}
Expr.substituteList(orderingExprs, combinedSMap);
LOG.debug("post-agg orderingExprs: " + Expr.debugString(orderingExprs));
// check that all post-agg exprs point to agg output
for (int i = 0; i < selectList.getItems().size(); ++i) {
if (!resultExprs.get(i).isBound(finalAggInfo.getAggTupleId())) {
throw new AnalysisException(
"select list expression not produced by aggregation output "
+ "(missing from GROUP BY clause?): "
+ selectList.getItems().get(i).getExpr().toSql());
}
}
if (orderByElements != null) {
for (int i = 0; i < orderByElements.size(); ++i) {
if (!orderingExprs.get(i).isBound(finalAggInfo.getAggTupleId())) {
throw new AnalysisException(
"ORDER BY expression not produced by aggregation output "
+ "(missing from GROUP BY clause?): "
+ orderByElements.get(i).getExpr().toSql());
}
}
}
if (havingPred != null) {
if (!havingPred.isBound(finalAggInfo.getAggTupleId())) {
throw new AnalysisException(
"HAVING clause not produced by aggregation output "
+ "(missing from GROUP BY clause?): "
+ havingClause.toSql());
}
}
}
