public void onMatch(RelOptRuleCall call) {
assert matches(call);
final JoinRel join = (JoinRel) call.rels[0];
final List<Integer> leftKeys = new ArrayList<Integer>();
final List<Integer> rightKeys = new ArrayList<Integer>();
RelNode right = join.getRight();
final RelNode left = join.getLeft();
RexNode remainingCondition =
RelOptUtil.splitJoinCondition(left, right, join.getCondition(), leftKeys, rightKeys);
assert leftKeys.size() == rightKeys.size();
final List<CorrelatorRel.Correlation> correlationList =
new ArrayList<CorrelatorRel.Correlation>();
if (leftKeys.size() > 0) {
final RelOptCluster cluster = join.getCluster();
final RexBuilder rexBuilder = cluster.getRexBuilder();
int k = 0;
RexNode condition = null;
for (Integer leftKey : leftKeys) {
Integer rightKey = rightKeys.get(k++);
final String dyn_inIdStr = cluster.getQuery().createCorrel();
final int dyn_inId = RelOptQuery.getCorrelOrdinal(dyn_inIdStr);
// Create correlation to say 'each row, set variable #id
// to the value of column #leftKey'.
correlationList.add(new CorrelatorRel.Correlation(dyn_inId, leftKey));
condition =
RelOptUtil.andJoinFilters(
rexBuilder,
condition,
rexBuilder.makeCall(
SqlStdOperatorTable.equalsOperator,
rexBuilder.makeInputRef(
right.getRowType().getFieldList().get(rightKey).getType(), rightKey),
rexBuilder.makeCorrel(
left.getRowType().getFieldList().get(leftKey).getType(), dyn_inIdStr)));
}
right = CalcRel.createFilter(right, condition);
}
RelNode newRel =
new CorrelatorRel(
join.getCluster(),
left,
right,
remainingCondition,
correlationList,
join.getJoinType());
call.transformTo(newRel);
}
/**
* Analyzes a rex predicate.
*
* @param rexPredicate predicate to be analyzed
* @return a list of SargBindings contained in the input rex predicate
*/
public List<SargBinding> analyzeAll(RexNode rexPredicate) {
sargBindingList = new ArrayList<SargBinding>();
sarg2RexMap = new HashMap<SargExpr, RexNode>();
nonSargFilterList = new ArrayList<RexNode>();
// Flatten out the RexNode tree into a list of terms that
// are AND'ed together
final List<RexNode> rexCFList = RelOptUtil.conjunctions(rexPredicate);
// In simple mode, each input ref can only be referenced once, so
// keep a list of them. We also only allow one non-point expression.
List<Integer> boundRefList = new ArrayList<Integer>();
boolean rangeFound = false;
for (RexNode rexPred : rexCFList) {
final SargBinding sargBinding = analyze(rexPred);
if (sargBinding != null) {
if (simpleMode) {
RexInputRef inputRef = sargBinding.getInputRef();
if (boundRefList.contains(inputRef.getIndex())) {
nonSargFilterList.add(rexPred);
continue;
} else {
boundRefList.add(inputRef.getIndex());
}
SargIntervalSequence sargSeq = sargBinding.getExpr().evaluate();
if (sargSeq.isRange()) {
if (rangeFound) {
nonSargFilterList.add(rexPred);
continue;
} else {
rangeFound = true;
}
}
}
sargBindingList.add(sargBinding);
sarg2RexMap.put(sargBinding.getExpr(), rexPred);
} else {
nonSargFilterList.add(rexPred);
}
}
// Reset the state variables used during analyze, just for sanity sake.
failed = false;
boundInputRef = null;
clearLeaf();
// Combine the AND terms back together.
recomposeConjunction();
return sargBindingList;
}
/**
* Returns whether the type of an array of expressions is compatible with a struct type.
*
* @param exprs Array of expressions
* @param type Type
* @param fail Whether to fail if there is a mismatch
* @return Whether every expression has the same type as the corresponding member of the struct
* type
* @see RelOptUtil#eq(String, RelDataType, String, RelDataType, boolean)
*/
public static boolean compatibleTypes(RexNode[] exprs, RelDataType type, boolean fail) {
final RelDataTypeField[] fields = type.getFields();
if (exprs.length != fields.length) {
assert !fail : "rowtype mismatches expressions";
return false;
}
for (int i = 0; i < fields.length; i++) {
final RelDataType exprType = exprs[i].getType();
final RelDataType fieldType = fields[i].getType();
if (!RelOptUtil.eq("type1", exprType, "type2", fieldType, fail)) {
return false;
}
}
return true;
}
public void assertConvertsTo(String sql, String plan, boolean trim) {
String sql2 = getDiffRepos().expand("sql", sql);
RelNode rel = convertSqlToRel(sql2);
assertTrue(rel != null);
assertValid(rel);
if (trim) {
final RelFieldTrimmer trimmer = createFieldTrimmer();
rel = trimmer.trim(rel);
assertTrue(rel != null);
assertValid(rel);
}
// NOTE jvs 28-Mar-2006: insert leading newline so
// that plans come out nicely stacked instead of first
// line immediately after CDATA start
String actual = NL + RelOptUtil.toString(rel);
diffRepos.assertEquals("plan", plan, actual);
}
/**
* Returns whether the leading edge of a given array of expressions is wholly {@link RexInputRef}
* objects with types corresponding to the underlying datatype.
*/
public static boolean containIdentity(RexNode[] exprs, RelDataType rowType, boolean fail) {
final RelDataTypeField[] fields = rowType.getFields();
if (exprs.length < fields.length) {
assert !fail : "exprs/rowType length mismatch";
return false;
}
for (int i = 0; i < fields.length; i++) {
if (!(exprs[i] instanceof RexInputRef)) {
assert !fail : "expr[" + i + "] is not a RexInputRef";
return false;
}
RexInputRef inputRef = (RexInputRef) exprs[i];
if (inputRef.getIndex() != i) {
assert !fail : "expr[" + i + "] has ordinal " + inputRef.getIndex();
return false;
}
if (!RelOptUtil.eq("type1", exprs[i].getType(), "type2", fields[i].getType(), fail)) {
return false;
}
}
return true;
}
public void onMatch(RelOptRuleCall call) {
AggregateRel aggRel = call.rel(0);
UnionRel unionRel = call.rel(1);
if (!unionRel.all) {
// This transformation is only valid for UNION ALL.
// Consider t1(i) with rows (5), (5) and t2(i) with
// rows (5), (10), and the query
// select sum(i) from (select i from t1) union (select i from t2).
// The correct answer is 15. If we apply the transformation,
// we get
// select sum(i) from
// (select sum(i) as i from t1) union (select sum(i) as i from t2)
// which yields 25 (incorrect).
return;
}
RelOptCluster cluster = unionRel.getCluster();
List<AggregateCall> transformedAggCalls =
transformAggCalls(
aggRel.getCluster().getTypeFactory(),
aggRel.getGroupSet().cardinality(),
aggRel.getAggCallList());
if (transformedAggCalls == null) {
// we've detected the presence of something like AVG,
// which we can't handle
return;
}
boolean anyTransformed = false;
// create corresponding aggs on top of each union child
List<RelNode> newUnionInputs = new ArrayList<RelNode>();
for (RelNode input : unionRel.getInputs()) {
boolean alreadyUnique = RelMdUtil.areColumnsDefinitelyUnique(input, aggRel.getGroupSet());
if (alreadyUnique) {
newUnionInputs.add(input);
} else {
anyTransformed = true;
newUnionInputs.add(
new AggregateRel(cluster, input, aggRel.getGroupSet(), aggRel.getAggCallList()));
}
}
if (!anyTransformed) {
// none of the children could benefit from the pushdown,
// so bail out (preventing the infinite loop to which most
// planners would succumb)
return;
}
// create a new union whose children are the aggs created above
UnionRel newUnionRel = new UnionRel(cluster, newUnionInputs, true);
AggregateRel newTopAggRel =
new AggregateRel(cluster, newUnionRel, aggRel.getGroupSet(), transformedAggCalls);
// In case we transformed any COUNT (which is always NOT NULL)
// to SUM (which is always NULLABLE), cast back to keep the
// planner happy.
RelNode castRel = RelOptUtil.createCastRel(newTopAggRel, aggRel.getRowType(), false);
call.transformTo(castRel);
}
