// PhysSequence::preCodeGen() -------------------------------------------
// Perform local query rewrites such as for the creation and
// population of intermediate tables, for accessing partitioned
// data. Rewrite the value expressions after minimizing the dataflow
// using the transitive closure of equality predicates.
//
// PhysSequence::preCodeGen() - is basically the same as the RelExpr::
// preCodeGen() except that here we replace the VEG references in the
// sortKey() list, as well as the selectionPred().
//
// Parameters:
//
// Generator *generator
// IN/OUT : A pointer to the generator object which contains the state,
// and tools (e.g. expression generator) to generate code for
// this node.
//
// ValueIdSet &externalInputs
// IN : The set of external Inputs available to this node.
//
//
RelExpr * PhysSequence::preCodeGen(Generator * generator,
const ValueIdSet & externalInputs,
ValueIdSet &pulledNewInputs)
{
if (nodeIsPreCodeGenned())
return this;
// Resolve the VEGReferences and VEGPredicates, if any, that appear
// in the Characteristic Inputs, in terms of the externalInputs.
//
getGroupAttr()->resolveCharacteristicInputs(externalInputs);
// My Characteristic Inputs become the external inputs for my children.
//
ValueIdSet childPulledInputs;
child(0) = child(0)->preCodeGen(generator, externalInputs, pulledNewInputs);
if (! child(0).getPtr())
return NULL;
// process additional input value ids the child wants
getGroupAttr()->addCharacteristicInputs(childPulledInputs);
pulledNewInputs += childPulledInputs;
// The VEG expressions in the selection predicates and the characteristic
// outputs can reference any expression that is either a potential output
// or a characteristic input for this RelExpr. Supply these values for
// rewriting the VEG expressions.
//
ValueIdSet availableValues;
getInputValuesFromParentAndChildren(availableValues);
// The sequenceFunctions() have access to only the Input
// Values. These can come from the parent or be the outputs of the
// child.
//
sequenceFunctions().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
sequencedColumns().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
requiredOrder().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
cancelExpr().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
partition().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
//checkPartitionChangeExpr().
// replaceVEGExpressions(availableValues,
// getGroupAttr()->getCharacteristicInputs());
// The selectionPred has access to only the output values generated by
// Sequence and input values from the parent.
//
getInputAndPotentialOutputValues(availableValues);
// Rewrite the selection predicates.
//
NABoolean replicatePredicates = TRUE;
selectionPred().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs(),
FALSE, // no key predicates here
0 /* no need for idempotence here */,
replicatePredicates
);
// Replace VEG references in the outputs and remove redundant
// outputs.
//
getGroupAttr()->resolveCharacteristicOutputs
(availableValues,
getGroupAttr()->getCharacteristicInputs());
addCancelExpr(generator->wHeap());
///addCheckPartitionChangeExpr(generator->wHeap());
transformOlapFunctions(generator->wHeap());
if ( getUnboundedFollowing() ) {
// Count this Seq as a BMO and add its needed memory to the total needed
generator->incrNumBMOs();
if ((ActiveSchemaDB()->getDefaults()).
getAsDouble(EXE_MEMORY_LIMIT_PER_CPU) > 0)
generator->incrBMOsMemory(getEstimatedRunTimeMemoryUsage(TRUE));
}
else
generator->incrNBMOsMemoryPerCPU(getEstimatedRunTimeMemoryUsage(TRUE));
markAsPreCodeGenned();
return this;
} // PhysSequence::preCodeGen
// PhysSample::preCodeGen() -------------------------------------------
// Perform local query rewrites such as for the creation and
// population of intermediate tables, for accessing partitioned
// data. Rewrite the value expressions after minimizing the dataflow
// using the transitive closure of equality predicates.
//
// PhysSample::preCodeGen() - is basically the same as the RelExpr::
// preCodeGen() except that here we replace the VEG references in the
// sortKey() list, as well as the selectionPred().
//
// Parameters:
//
// Generator *generator
// IN/OUT : A pointer to the generator object which contains the state,
// and tools (e.g. expression generator) to generate code for
// this node.
//
// ValueIdSet &externalInputs
// IN : The set of external Inputs available to this node.
//
//
RelExpr * PhysSample::preCodeGen(Generator * generator,
const ValueIdSet & externalInputs,
ValueIdSet &pulledNewInputs)
{
// Do nothing if this node has already been processed.
//
if (nodeIsPreCodeGenned())
return this;
// Resolve the VEGReferences and VEGPredicates, if any, that appear
// in the Characteristic Inputs, in terms of the externalInputs.
//
getGroupAttr()->resolveCharacteristicInputs(externalInputs);
// My Characteristics Inputs become the external inputs for my children.
// preCodeGen my only child.
//
ValueIdSet childPulledInputs;
child(0) = child(0)->preCodeGen(generator, externalInputs, pulledNewInputs);
if(!child(0).getPtr())
return NULL;
// Process additional any additional inputs the child wants.
//
getGroupAttr()->addCharacteristicInputs(childPulledInputs);
pulledNewInputs += childPulledInputs;
// The sampledCols() only have access to the Input Values.
// These can come from the parent or be the outputs of the child.
// Compute the set of available values for the sampledCols() and use
// these to resolve any VEG references that the sampledCols() may need.
//
ValueIdSet availableValues;
getInputValuesFromParentAndChildren(availableValues);
sampledColumns().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs());
// Ditto, for the balance expression.
//
balanceExpr().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs());
requiredOrder().
replaceVEGExpressions(availableValues,
getGroupAttr()->getCharacteristicInputs());
// The selectionPred has access to only the output values generated by
// Sequence and input values from the parent. Compute the set of available
// values for the selectionPred and resolve any VEG references
// that the selection predicates may need.
//
getInputAndPotentialOutputValues(availableValues);
NABoolean replicatePredicates = TRUE;
selectionPred().replaceVEGExpressions
(availableValues,
getGroupAttr()->getCharacteristicInputs(),
FALSE, // no key predicates here
0 /* no need for idempotence here */,
replicatePredicates
);
// Resolve VEG references in the outputs and remove redundant
// outputs.
//
getGroupAttr()->resolveCharacteristicOutputs
(availableValues,
getGroupAttr()->getCharacteristicInputs());
// Mark this node as done and return.
//
markAsPreCodeGenned();
return this;
} // PhysSample::preCodeGen