public class JoinPushThroughJoinRule extends RelOptRule
Thus, (A join B) join C
becomes (A join C) join B
. The
advantage of applying this rule is that it may be possible to apply
conditions earlier. For instance,
(sales as s join product_class as pc on true) join product as p on s.product_id = p.product_id and p.product_class_id = pc.product_class_id
becomes
(sales as s join product as p on s.product_id = p.product_id) join product_class as pc on p.product_class_id = pc.product_class_id
Before the rule, one join has two conditions and the other has none
(ON TRUE
). After the rule, each join has one condition.
Modifier and Type | Field and Description |
---|---|
static RelOptRule |
LEFT
Instance of the rule that works on logical joins only, and pushes to the
left.
|
private boolean |
right |
static RelOptRule |
RIGHT
Instance of the rule that works on logical joins only, and pushes to the
right.
|
description, operands, relBuilderFactory
Constructor and Description |
---|
JoinPushThroughJoinRule(java.lang.String description,
boolean right,
java.lang.Class<? extends Join> clazz,
RelBuilderFactory relBuilderFactory)
Creates a JoinPushThroughJoinRule.
|
JoinPushThroughJoinRule(java.lang.String description,
boolean right,
java.lang.Class<? extends Join> clazz,
RelFactories.ProjectFactory projectFactory)
Deprecated.
|
Modifier and Type | Method and Description |
---|---|
void |
onMatch(RelOptRuleCall call)
Receives notification about a rule match.
|
private void |
onMatchLeft(RelOptRuleCall call)
Similar to
onMatch(org.apache.calcite.plan.RelOptRuleCall) , but swaps the upper sibling with the left
of the two lower siblings, rather than the right. |
private void |
onMatchRight(RelOptRuleCall call) |
(package private) static void |
split(RexNode condition,
ImmutableBitSet bitSet,
java.util.List<RexNode> intersecting,
java.util.List<RexNode> nonIntersecting)
Splits a condition into conjunctions that do or do not intersect with
a given bit set.
|
any, convert, convert, convertList, convertOperand, convertOperand, equals, equals, getOperand, getOperands, getOutConvention, getOutTrait, hashCode, matches, none, operand, operand, operand, operand, operand, operandJ, operandJ, some, toString, unordered
public static final RelOptRule RIGHT
public static final RelOptRule LEFT
private final boolean right
public JoinPushThroughJoinRule(java.lang.String description, boolean right, java.lang.Class<? extends Join> clazz, RelBuilderFactory relBuilderFactory)
@Deprecated public JoinPushThroughJoinRule(java.lang.String description, boolean right, java.lang.Class<? extends Join> clazz, RelFactories.ProjectFactory projectFactory)
public void onMatch(RelOptRuleCall call)
RelOptRule
call.rels
holds the set of relational
expressions which match the operands to the rule;
call.rels[0]
is the root expression.
Typically a rule would check that the nodes are valid matches, creates
a new expression, then calls back RelOptRuleCall.transformTo(org.apache.calcite.rel.RelNode, java.util.Map<org.apache.calcite.rel.RelNode, org.apache.calcite.rel.RelNode>)
to
register the expression.
onMatch
in class RelOptRule
call
- Rule callRelOptRule.matches(RelOptRuleCall)
private void onMatchRight(RelOptRuleCall call)
private void onMatchLeft(RelOptRuleCall call)
onMatch(org.apache.calcite.plan.RelOptRuleCall)
, but swaps the upper sibling with the left
of the two lower siblings, rather than the right.static void split(RexNode condition, ImmutableBitSet bitSet, java.util.List<RexNode> intersecting, java.util.List<RexNode> nonIntersecting)
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