/**
* Determines if a filter condition is a simple one and returns the parameters corresponding to
* the simple filters.
*
* @param calcRel original CalcRel
* @param filterExprs filter expression being analyzed
* @param filterList returns the list of filter ordinals in the simple expression
* @param literals returns the list of literals to be used in the simple comparisons
* @param op returns the operator to be used in the simple comparison
* @return true if the filter condition is simple
*/
private boolean isConditionSimple(
CalcRel calcRel,
RexNode filterExprs,
List<Integer> filterList,
List<RexLiteral> literals,
List<CompOperatorEnum> op) {
SargFactory sargFactory = new SargFactory(calcRel.getCluster().getRexBuilder());
SargRexAnalyzer rexAnalyzer = sargFactory.newRexAnalyzer(true);
List<SargBinding> sargBindingList = rexAnalyzer.analyzeAll(filterExprs);
// Currently, it's all or nothing. So, if there are filters rejected
// by the analyzer, we can't process a subset using the reshape
// exec stream
if (rexAnalyzer.getNonSargFilterRexNode() != null) {
return false;
}
List<RexInputRef> filterCols = new ArrayList<RexInputRef>();
List<RexNode> filterOperands = new ArrayList<RexNode>();
if (FennelRelUtil.extractSimplePredicates(sargBindingList, filterCols, filterOperands, op)) {
for (RexInputRef filterCol : filterCols) {
filterList.add(filterCol.getIndex());
}
for (RexNode operand : filterOperands) {
literals.add((RexLiteral) operand);
}
return true;
} else {
return false;
}
}
/**
* Reconstructs a rex predicate from a list of SargBindings which are AND'ed together.
*
* @param sargBindingList list of SargBindings to be converted.
* @return the rex predicate reconstructed from the list of SargBindings.
*/
public RexNode getSargBindingListToRexNode(List<SargBinding> sargBindingList) {
if (sargBindingList.isEmpty()) {
return null;
}
RexNode newAndNode = sarg2RexMap.get(sargBindingList.get(0).getExpr());
for (int i = 1; i < sargBindingList.size(); i++) {
RexNode nextNode = sarg2RexMap.get(sargBindingList.get(i).getExpr());
newAndNode =
factory.getRexBuilder().makeCall(SqlStdOperatorTable.andOperator, newAndNode, nextNode);
}
return newAndNode;
}
/**
* Reconstructs a rex predicate from the non-sargable filter predicates which are AND'ed together.
*
* @return the rex predicate reconstructed from the non-sargable predicates.
*/
public RexNode getNonSargFilterRexNode() {
if (nonSargFilterList.isEmpty()) {
return null;
}
RexNode newAndNode = nonSargFilterList.get(0);
for (int i = 1; i < nonSargFilterList.size(); i++) {
newAndNode =
factory
.getRexBuilder()
.makeCall(SqlStdOperatorTable.andOperator, newAndNode, nonSargFilterList.get(i));
}
return newAndNode;
}
/** Reconstructs a rex predicate from a list of SargExprs which will be AND'ed together. */
private void recomposeConjunction() {
for (int i = 0; i < sargBindingList.size(); i++) {
final SargBinding currBinding = sargBindingList.get(i);
final RexInputRef currRef = currBinding.getInputRef();
SargExpr currSargExpr = currBinding.getExpr();
RexNode currAndNode = sarg2RexMap.get(currSargExpr);
// don't need this anymore
// will be have new mapping put back if currSargExpr remain
// unchanged.
sarg2RexMap.remove(currSargExpr);
boolean recomp = false;
// search the rest of the list to find SargExpr on the same col.
ListIterator<SargBinding> iter = sargBindingList.listIterator(i + 1);
while (iter.hasNext()) {
final SargBinding nextBinding = iter.next();
final RexInputRef nextRef = nextBinding.getInputRef();
final SargExpr nextSargExpr = nextBinding.getExpr();
if (nextRef.getIndex() == currRef.getIndex()) {
// build new SargExpr
SargSetExpr expr =
factory.newSetExpr(currSargExpr.getDataType(), SargSetOperator.INTERSECTION);
expr.addChild(currSargExpr);
expr.addChild(nextSargExpr);
// build new RexNode
currAndNode =
factory
.getRexBuilder()
.makeCall(
SqlStdOperatorTable.andOperator, currAndNode, sarg2RexMap.get(nextSargExpr));
currSargExpr = expr;
sarg2RexMap.remove(nextSargExpr);
iter.remove();
recomp = true;
}
}
if (recomp) {
assert !simpleMode;
if (!testDynamicParamSupport(currSargExpr)) {
// Oops, we can't actually support the conjunction we
// recomposed. Toss it. (We could do a better job by at
// least using part of it, but the effort might be better
// spent on implementing deferred expression evaluation.)
nonSargFilterList.add(currAndNode);
sargBindingList.remove(i);
continue;
}
}
if (recomp) {
SargBinding newBinding = new SargBinding(currSargExpr, currRef);
sargBindingList.remove(i);
sargBindingList.add(i, newBinding);
}
sarg2RexMap.put(currSargExpr, currAndNode);
}
}
