void
RelSequence::addCancelExpr(CollHeap *wHeap)
{
  ItemExpr *cPred = NULL;

  if (this->partition().entries() > 0)
  {
    return;
  }
  if(cancelExpr().entries() > 0) 
  {
    return;
  }

  for(ValueId valId = selectionPred().init();
      selectionPred().next(valId);
      selectionPred().advance(valId)) 
  {
    ItemExpr *pred = valId.getItemExpr();

    // Look for preds that select a prefix of the sequence.
    // Rank() < const; Rank <= const; const > Rank; const >= Rank
    ItemExpr *op1 = NULL;
    ItemExpr *op2 = NULL;

    if(pred->getOperatorType() == ITM_LESS ||
       pred->getOperatorType() == ITM_LESS_EQ) 
    {
      op1 = pred->child(0);
      op2 = pred->child(1);
    }
    else if (pred->getOperatorType() == ITM_GREATER ||
             pred->getOperatorType() == ITM_GREATER_EQ) 
    {
      op1 = pred->child(1);
      op2 = pred->child(0);
    }
    NABoolean negate;
    if (op1 && op2 &&
        (op2->getOperatorType() == ITM_CONSTANT || 
         op2->getOperatorType() == ITM_DYN_PARAM)  &&
         (op1->getOperatorType() == ITM_OLAP_RANK ||
          op1->getOperatorType() == ITM_OLAP_DRANK ||
          (op1->getOperatorType() == ITM_OLAP_COUNT &&
           op1->child(0)->getOperatorType() == ITM_CONSTANT &&
           !op1->child(0)->castToConstValue(negate)->isNull())))
    {
       cPred = new(wHeap) UnLogic(ITM_NOT, pred);
       //break at first occurence
       break;
    }
  }
  
  if(cPred) 
  {
    cPred->synthTypeAndValueId(TRUE);
    cancelExpr().insert(cPred->getValueId());
  }
}
// A transformation method for protecting sequence functions from not
// being evaluated due to short-circuit evaluation.
//
void Case::protectiveSequenceFunctionTransformation(Generator *generator)
{
  // Recurse on the children
  //
  ItemExpr::protectiveSequenceFunctionTransformation(generator);

  // Remove the original value id from the node being transformed and
  // assign it a new value id.
  //
  ValueId id = getValueId();
  setValueId(NULL_VALUE_ID);
  synthTypeAndValueId(TRUE);

  // Construct the new subtree.
  //
  // Case -- force evaluation of all the WHEN, THEN and ELSE parts
  //
  // CASE(IFE1(W1,T1,IFE2(W2,T2,IFE3(...)))) ==>
  //   BLOCK(BLOCK(BLOCK(W1,T1),BLOCK(W2,T2)), CASE(...))
  //
  // Decend the ITM_IF_THEN_ELSE tree pulling out each WHEN and THEN pair.
  // Mate each pair with a block and attach them to the protected block, 
  // which contains all of the WHEN/THEN pairs for the entire tree.
  // Also, pull out any CASE operands and attach them to the protected
  // block as well.
  //
  ItemExpr *block = NULL;
  ItemExpr *ife = child(0);
  for(; (ife != NULL) && (ife->getOperatorType() == ITM_IF_THEN_ELSE);
       ife = ife->child(2))
    {
      ItemExpr *sub = new(generator->wHeap())
	ItmBlockFunction(ife->child(0), ife->child(1));
      if(block)
	block = new(generator->wHeap()) ItmBlockFunction(sub, block);
      else
	block = sub;
    }      

  // Add the ELSE condition, if any to the protected block
  //
  if(ife)
    block = new(generator->wHeap()) ItmBlockFunction(ife, block);

  // Construct the top-level block function. The left child is the protected
  // block, which contains all of the expresssions that need to be 
  // pre-evaluated. This right child is the original case statement.
  //
  block = new(generator->wHeap()) ItmBlockFunction(block, this);

  // Replace the old expression with the new expression for the
  // original id
  //
  id.replaceItemExpr(block);

  // Run the new expression through type and value id synthesis
  //
  block->synthTypeAndValueId(TRUE);
}
// index access (both reference and value)
ItemExpr * ItemExprTreeAsList::operator [] (CollIndex i)
{
  
  //     think of three different cases:
  // 
  //     a) i is out of range (< 0 or >= #entries)
  // 
  //     b) the node we are looking for is neither the only nor the last
  //        node in the backbone
  // 
  //     c) we are looking for the last element in the backbone (which
  //        may be the only element)
  // 

  ItemExpr *aNodePtr = *treePtr_;
  Int32 j = (Int32) i; // j may become negative, i may be unsigned

  if (j < 0)
    return NULL; // case a

  if (aNodePtr->getOperatorType() != operator_ AND
      j == 0)
    return aNodePtr; // case b

  while (aNodePtr != NULL AND j >= 0)
    {
      if (aNodePtr->getOperatorType() == operator_ AND
	  aNodePtr->getArity() >= 2)
	{
	  if (shape_ == LEFT_LINEAR_TREE)
	    {
	      if (j == 0)
		aNodePtr = aNodePtr->child(1); // case b
	      else
		aNodePtr = aNodePtr->child(0);
	    }
	  else if (shape_ == RIGHT_LINEAR_TREE)
	    {
	      if (j == 0)
		aNodePtr = aNodePtr->child(0); // case b
	      else
		aNodePtr = aNodePtr->child(1);
	    }
	  else
	    ABORT("can't do bushy trees");
	}
      j--;
    }

  // if we are looking for the only element, the while loop
  // is not executed at all

  return aNodePtr;

}
// return number of entries
Lng32 ItemExprTreeAsList::entries() const
{
  ItemExpr *aNode = *treePtr_;
  Lng32 result = 0;

  while (aNode != NULL)
    {
      result++;
      if (aNode->getOperatorType() == operator_ AND
	  aNode->getArity() >= 2)
	{
	  if (shape_ == LEFT_LINEAR_TREE)
	    aNode = aNode->child(0);
	  else
	    if (shape_ == RIGHT_LINEAR_TREE)
	      aNode = aNode->child(1);
	    else
	      ABORT("can't do other than right-linear trees");
	}
      else
	aNode = NULL;
    }
  return result;
}
// check whether an element is in the collection
NABoolean ItemExprTreeAsList::contains(const ItemExpr *treeToCheck)
{
  
  ItemExpr *aNodePtr = *treePtr_;

  while (aNodePtr != NULL)
    {
      if (aNodePtr == treeToCheck)
	return TRUE;

      if (aNodePtr->getOperatorType() == operator_ AND
	  aNodePtr->getArity() >= 2)
	{
	  if (shape_ == RIGHT_LINEAR_TREE)
	    aNodePtr = aNodePtr->child(1);
	  else
	    ABORT("can't do other than right-linear trees");
	}
      else
	aNodePtr = NULL;
    }
  return FALSE;
}
Exemplo n.º 6
0
short BiLogic::codeGen(Generator * generator)
{
  Attributes ** attr;

  if (generator->getExpGenerator()->genItemExpr(this, &attr, (1+getArity()), 0) == 1)
    return 0;
    
  Space * space = generator->getSpace();
  ExpGenerator * expGen = generator->getExpGenerator();

  // Normally, if code for a value id has been generated, and if
  // that value id is seen again, then code is not generated. The
  // location where the result is available is returned instead.
  // The case of a logical operator is different. Code is generated
  // again if a value id from the left child is also present in
  // the right child. This is done 
  // because at expression evaluation time, some of the expressions
  // may be skipped due to short circuit evaluation. 
  //
  // Allocate a new map table before generating code for each child.
  // This map table contains all the temporary results produced by
  // the child. 
  // Remove this map table after generating code for each child.
  generator->appendAtEnd();
  expGen->incrementLevel();

  codegen_and_set_attributes(generator, attr, 2); 
  //  generator->getExpGenerator()->setClauseLinked(FALSE);
  // child(0)->codeGen(generator);
  // attr[1] = generator->getAttr(child(0));
  // generator->getExpGenerator()->setClauseLinked(FALSE);

  /* generate boolean short circuit code */
  Attributes ** branch_attr = new(generator->wHeap()) Attributes * [2];

  branch_attr[0] = attr[0]->newCopy(generator->wHeap());
  branch_attr[0]->copyLocationAttrs(attr[0]);

  branch_attr[1] = attr[1]->newCopy(generator->wHeap());
  branch_attr[1]->copyLocationAttrs(attr[1]);

  branch_attr[0]->resetShowplan();
  ex_branch_clause * branch_clause 
    = new(space) ex_branch_clause(getOperatorType(), branch_attr, space);
  
  generator->getExpGenerator()->linkClause(0, branch_clause);
 
  generator->removeLast();
  expGen->decrementLevel();
  generator->appendAtEnd();
  expGen->incrementLevel();

  ValueIdSet markedEntries;
  // This ia a MapTable entry related fix for RangeSpec transformation.
  if( child(1)->getOperatorType() == ITM_RANGE_SPEC_FUNC )
    markGeneratedEntries(generator, child(1)->child(1), markedEntries);
  else
    markGeneratedEntries(generator, child(1), markedEntries);
//  if( child(1)->getOperatorType() == ITM_RANGE_SPEC_FUNC )
//    child(1)->child(1)->codeGen(generator);
//  else
    child(1)->codeGen(generator);
  ItemExpr *rightMost;
  if( child(1)->getOperatorType() == ITM_RANGE_SPEC_FUNC )
    rightMost = child(1)->child(1)->castToItemExpr();
  else
    rightMost = child(1)->castToItemExpr();

  while (rightMost->getOperatorType() == ITM_ITEM_LIST)
    rightMost = rightMost->child(1)->castToItemExpr();

  attr[2] = generator->
    getMapInfo(rightMost->getValueId())->getAttr();

  ex_bool_clause * bool_clause =
    new(space) ex_bool_clause(getOperatorType(), attr, space);

  generator->getExpGenerator()->linkClause(this, bool_clause);

  branch_clause->set_branch_clause((ex_clause *)bool_clause);
  
  generator->removeLast();
  expGen->decrementLevel();
  if( child(1)->getOperatorType() == ITM_RANGE_SPEC_FUNC )
    unGenerate(generator, child(1)->child(1));
  else
    unGenerate(generator, child(1));
  generateMarkedEntries(generator, markedEntries);

  return 0;
}
Exemplo n.º 7
0
// change literals of a cacheable query into ConstantParameters 
ItemExpr* UDFunction::normalizeForCache(CacheWA& cwa, BindWA& bindWA)
{
  if (nodeIsNormalizedForCache()) { 
    return this; 
  }
  // Since the UDFunction::transformNode refers to both the 
  // inputVars_ ValueIdSet and the children array we need to make sure
  // they are consistent.
  // The children array may contain cast() of the expressions in inputVars_


  // If we have a UUDF function the inputs that were given 
  // at parse time, really do not reflect reality anymore.
  // So here we will simply reinitialize them with what we find in the
  // inputVars_.

  CMPASSERT(udfDesc_); // we better have one after binding.
  NABoolean isUUDF(udfDesc_->isUUDFRoutine());

  // Save off a copy of the original inputVars_ set.
  ValueIdSet origInputVars(inputVars_);


  // Loop through the given inputs
  for (Int32 x = 0; x < getArity(); x++)
  {
    NABoolean origInputIsChildOfCast(FALSE);
    ItemExpr * origIe = child(x);
    ItemExpr * newIe = NULL;
    ValueId vid = origIe->getValueId();
    if (cwa.getPhase() == CmpMain::BIND) 
    {
      if (origIe->isSafelyCoercible(cwa)) 
      {
   
        // fix CR 10-010726-4109: make sure queries with constants that 
        // cannot be safely backpatched such as 
        //   select case smallintcol when 4294967393 then 'max' end from t
        // are not parameterized
   
   
        newIe = origIe->normalizeForCache(cwa, bindWA);
   
        if (newIe != origIe )
        {
          // normalizeForCache returned a new ItemExpr. We have to update
          // the UDFunction inputVars_ set, as this is used to determine
          // characteristic inputs for IsolatedScalarUDF at transform time.

          child(x) = newIe;

          // Is it a input that UDFunction::bindNode put a cast around?
          if ((origIe->getOperatorType() == ITM_CAST) &&
              (origInputVars.contains(origIe->child(0)->getValueId())))
          {

            // Since the original child was a CAST that UDFunction::bindNode
            // created, check to see if that CAST's child is part of the new
            // expression, if it is, we don't have to do anything, since the
            // CASTED value is part of the inputVars set, otherwise, we have
            // to update the inputVars set to keep the characteristic inputs
            // consistent.
            if (! newIe->referencesTheGivenValue(
                    origIe->child(0)->getValueId()), TRUE)
            {
              // remove the original input from inputVars. It is the child
              // of origIe because origIe is a cast that UDFunction::bindNode
              // introduced.
              inputVars_ -= origIe->child(0)->getValueId();

              if (newIe->getOperatorType() == ITM_CAST)
              {
                // If the new expression is a CAST, we assume the child is the
                // real input. We don't expect CAST(CAST(CAST(expr))) type
                // expressions only simple CAST(expr) ones.
                inputVars_ += newIe->child(0)->getValueId();
              }
              else
              {
                // add the newIe itself if it was not a CAST.
                inputVars_ += newIe->getValueId();
              }
            }
          }
          else
          {
            // If the newIe doesn't contain the original one, we need to update
            // the inputVars set.
            if (! newIe->referencesTheGivenValue(
                    origIe->getValueId()), TRUE)
            {
              // the origIe was not a CAST introduced by UDFunction::bindNode()
              if (newIe->getOperatorType() == ITM_CAST) 
              {
                if (!origInputVars.contains(newIe->child(0)->getValueId()))
                {
                  inputVars_ -= origIe->getValueId();
                  // If the new expression is a CAST, we assume the child is the
                  // real input. We don't expect CAST(CAST(CAST(expr))) type
                  // expressions only simple CAST(expr) ones.
                  inputVars_ += newIe->child(0)->getValueId();
                }
                // we don't need to update inputVars_ if the origInputVars 
                // contains the valueId of the newIe child already.
              } 
              else
              {
                // This is an entirely new input. Remove the old one, and 
                // add in the new.
                inputVars_ -= origIe->getValueId();
                inputVars_ += newIe->getValueId();
              }
            }
          }
        }
      }
    }
  }

  markAsNormalizedForCache();
  return this;
}
// getHistoryAttributes
//
// Helper function that traverses the set of root sequence functions
// supplied by the compiler and constructs the set of all of the
// attributes that must be materialized in the history row.
// 
void PhysSequence::getHistoryAttributes(const ValueIdSet &sequenceFunctions,
                                        const ValueIdSet &outputFromChild,
                                        ValueIdSet &historyAttributes,
                                        NABoolean addConvNodes,
                                        CollHeap *wHeap,
                                        ValueIdMap *origAttributes) const
{
  if(addConvNodes && !origAttributes) {
    origAttributes = new (wHeap) ValueIdMap();
  }

  ValueIdSet children;
  for(ValueId valId = sequenceFunctions.init();
      sequenceFunctions.next(valId);
      sequenceFunctions.advance(valId)) {

    if(valId.getItemExpr()->isASequenceFunction()) {
      ItemExpr *itmExpr = valId.getItemExpr();

      switch(itmExpr->getOperatorType())
        {
          // The child needs to be in the history row.
          //
        case ITM_OFFSET:
        case ITM_ROWS_SINCE:
        case ITM_THIS:
        case ITM_NOT_THIS:

          // If the child needs to be in the history buffer, then
          // add a Convert node to force the value to be moved to the
          // history buffer.
          if (addConvNodes)
            {
              itmExpr->child(0) = 
                addConvNode(itmExpr->child(0), origAttributes, wHeap);
            }
          historyAttributes += itmExpr->child(0)->getValueId();
          break;

          // The sequence function needs to be in the history row.
          //
        case ITM_RUNNING_SUM:
        case ITM_RUNNING_COUNT:
        case ITM_RUNNING_MIN:
        case ITM_RUNNING_MAX:
        case ITM_LAST_NOT_NULL:
          historyAttributes += itmExpr->getValueId();
          break;
/*
        // after PhysSequence precode gen OLAP sum and count are already transform,ed into running
        // this is used during optimization phase-- 
        case ITM_OLAP_SUM:
        case ITM_OLAP_COUNT:
        case ITM_OLAP_RANK:
        case ITM_OLAP_DRANK:
          if (addConvNodes)
            {
              itmExpr->child(0) = 
                addConvNode(itmExpr->child(0), origAttributes, wHeap);
            }

          historyAttributes += itmExpr->child(0)->getValueId();
          //historyAttributes += itmExpr->getValueId();	  
          break;
*/
          // The child and sequence function need to be in the history row.
          //
        case ITM_OLAP_MIN:
        case ITM_OLAP_MAX:
        case ITM_MOVING_MIN:
        case ITM_MOVING_MAX:

          // If the child needs to be in the history buffer, then
          // add a Convert node to force the value to be moved to the
          // history buffer.
          if (addConvNodes)
            {
              itmExpr->child(0) = 
                addConvNode(itmExpr->child(0), origAttributes, wHeap);
            }

          historyAttributes += itmExpr->child(0)->getValueId();
          historyAttributes += itmExpr->getValueId();	  
          break;

        case ITM_RUNNING_CHANGE:
          if (itmExpr->child(0)->getOperatorType() == ITM_ITEM_LIST)
            {
              // child is a multi-valued expression
              // 
              ExprValueId treePtr = itmExpr->child(0);

              ItemExprTreeAsList changeValues(&treePtr,
                                              ITM_ITEM_LIST,
                                              RIGHT_LINEAR_TREE);

              CollIndex nc = changeValues.entries();
              
              ItemExpr *newChild = NULL;
              if(addConvNodes) {
                newChild = addConvNode(changeValues[nc-1], origAttributes, wHeap);
                historyAttributes += newChild->getValueId();
              } else {
                historyAttributes += changeValues[nc-1]->getValueId();
              }

              // add each item in the list
              // 
              for (CollIndex i = nc; i > 0; i--)
                {
                  if(addConvNodes) {
                    ItemExpr *conv
                      = addConvNode(changeValues[i-1], origAttributes, wHeap);

                    newChild = new(wHeap) ItemList(conv, newChild);
                    newChild->synthTypeAndValueId(TRUE);
                    historyAttributes += conv->getValueId();
                  } else {
                    historyAttributes += changeValues[i-1]->getValueId();
                  }
                }

              if(addConvNodes) {
                itmExpr->child(0) = newChild;
              }
            }
          else
            {

              // If the child needs to be in the history buffer, then
              // add a Convert node to force the value to be moved to the
              // history buffer.
              if (addConvNodes)
                {
                  itmExpr->child(0) = 
                    addConvNode(itmExpr->child(0), origAttributes, wHeap);
                }

              historyAttributes += itmExpr->child(0)->getValueId();
            }

          historyAttributes += itmExpr->getValueId();  
          break;

        default:
          CMPASSERT(0);
        }
    }

    // Gather all the children, and if not empty, recurse down to the
    // next level of the tree.
    //
    for(Lng32 i = 0; i < valId.getItemExpr()->getArity(); i++) 
    {
      if (!outputFromChild.contains(valId.getItemExpr()->child(i)->getValueId()))
        //!valId.getItemExpr()->child(i)->nodeIsPreCodeGenned()) 
      {
        children += valId.getItemExpr()->child(i)->getValueId();
      }
    }
  }
  
  if (NOT children.isEmpty())
  {
    getHistoryAttributes( children,
                          outputFromChild,
                          historyAttributes, 
                          addConvNodes, 
                          wHeap, 
                          origAttributes);
  }

} // PhysSequence::getHistoryAttributes
// computeHistoryBuffer
//
// Helper function that traverses the set of root sequence functions
// supplied by the compiler and dynamically determines the size
// of the history buffer.
// 
void PhysSequence::computeHistoryRows(const ValueIdSet &sequenceFunctions,//historyIds
                                      Lng32 &computedHistoryRows,
                                      Lng32 &unableToCalculate,
                                      NABoolean &unboundedFollowing, 
                                      Lng32 &minFollowingRows,
                                      const ValueIdSet &outputFromChild) 
{
  ValueIdSet children;
  ValueIdSet historyAttributes;
  Lng32 value = 0;

  for(ValueId valId = sequenceFunctions.init();
      sequenceFunctions.next(valId);
      sequenceFunctions.advance(valId)) 
  {
    if(valId.getItemExpr()->isASequenceFunction()) 
    {
      ItemExpr *itmExpr = valId.getItemExpr();

      switch(itmExpr->getOperatorType())
        {

        // THIS and NOT THIS are not dynamically computed
        //
        case ITM_THIS:
        case ITM_NOT_THIS:
          break;

        // The RUNNING functions and LastNotNull all need to go back just one row.
        //
        case ITM_RUNNING_SUM:
        case ITM_RUNNING_COUNT:
        case ITM_RUNNING_MIN:
        case ITM_RUNNING_MAX:
        case ITM_RUNNING_CHANGE:   
        case ITM_LAST_NOT_NULL:
          computedHistoryRows = MAXOF(computedHistoryRows, 2);
          break;
        ///set to unable to compute for now-- will change later to compte values from frameStart_ and frameEnd_
        case ITM_OLAP_SUM:
        case ITM_OLAP_COUNT:
        case ITM_OLAP_MIN:
        case ITM_OLAP_MAX:
        case ITM_OLAP_RANK:
        case ITM_OLAP_DRANK:
        {
          if ( !outputFromChild.contains(itmExpr->getValueId()))
          {
            ItmSeqOlapFunction * olap = (ItmSeqOlapFunction*)itmExpr;

            if (olap->isFrameStartUnboundedPreceding()) //(olap->getframeStart() == - INT_MAX)
            {
              computedHistoryRows = MAXOF(computedHistoryRows, 2);
            }
            else
            {
              computedHistoryRows = MAXOF(computedHistoryRows, ABS(olap->getframeStart()) + 2);
            }
            if (!olap->isFrameEndUnboundedFollowing()) //(olap->getframeEnd() != INT_MAX)
            {
              computedHistoryRows = MAXOF(computedHistoryRows, ABS(olap->getframeEnd()) + 1);
            }

            if (olap->isFrameEndUnboundedFollowing()) //(olap->getframeEnd() == INT_MAX)
            {
              unboundedFollowing = TRUE;
              if (olap->getframeStart() > 0) 
              {
                minFollowingRows = ((minFollowingRows > olap->getframeStart()) ?  
                                    minFollowingRows : olap->getframeStart());
              }
            } else  if (olap->getframeEnd() > 0)
            {
              minFollowingRows = ((minFollowingRows > olap->getframeEnd()) ?  
                                  minFollowingRows : olap->getframeEnd());
            }
          }
        }

        break;

        // If 'rows since', we cannot determine how much history is needed.  
        case ITM_ROWS_SINCE:
          unableToCalculate = 1;
          break;

        // The MOVING and OFFSET functions need to go back as far as the value
        // of their second child.
        //
        //  The second argument can be:
        //    Constant: for these, we can use the constant value to set the upper bound
        //              for the history buffer.
        //    ItmScalarMinMax(child0, child1) (with operType = ITM_SCALAR_MIN)  
        //      - if child0 or child1 is a constant, then we can use either one
        //        to set the upper bound.
        
        case ITM_MOVING_MIN:
        case ITM_MOVING_MAX:
        case ITM_OFFSET:
         
          for(Lng32 i = 1; i < itmExpr->getArity(); i++)
          {
            if (itmExpr->child(i)->getOperatorType() != ITM_NOTCOVERED)
            {
              ItemExpr * exprPtr = itmExpr->child(i);
              NABoolean negate;
              ConstValue *cv = exprPtr->castToConstValue(negate);
              if (cv AND cv->canGetExactNumericValue())
                {
                  Lng32 scale;
                  Int64 value64 = cv->getExactNumericValue(scale);

                  if(scale == 0 && value64 >= 0 && value64 < INT_MAX) 
                    {
                      value64 = (negate ? -value64 : value64);
                      value = MAXOF((Lng32)value64, value);
                    }
                 }
              else
                {
                  if (exprPtr->getOperatorType() == ITM_SCALAR_MIN)
                    {
                      for(Lng32 j = 0; j < exprPtr->getArity(); j++)
                        {
                          if (exprPtr->child(j)->getOperatorType()
                            != ITM_NOTCOVERED)
                            {
                               ItemExpr * exprPtr1 = exprPtr->child(j);
                               NABoolean negate1;
                               ConstValue *cv1 = exprPtr1->castToConstValue(negate1);
                               if (cv1 AND cv1->canGetExactNumericValue())
                                 {
                                   Lng32 scale1;
                                   Int64 value64_1 = cv1->getExactNumericValue(scale1);

                                   if(scale1 == 0 && value64_1 >= 0 && value64_1 < INT_MAX) 
                                     {
                                       value64_1 = (negate1 ? -value64_1 : value64_1);
                                       value = MAXOF((Lng32)value64_1, value);
                                     }
                                  }
                              }
                          }   
                     }   
                }  // end of inner else
            }// end of if

          }// end of for

          // Check if the value is greater than zero.
          // If it is, then save the value, but first
          // increment the returned ConstValue by one.
          // Otherwise, the offset or moving value was unable
          // to be calculated.

          if (value > 0)
          {
            value++;
            computedHistoryRows = MAXOF(computedHistoryRows, value);
            value = 0;
          }
          else
            unableToCalculate = 1;

          break;

        default:
          CMPASSERT(0);
        }
    }
   
    // Gather all the children, and if not empty, recurse down to the
    // next level of the tree.
    //

    for(Lng32 i = 0; i < valId.getItemExpr()->getArity(); i++) {
      if (//valId.getItemExpr()->child(i)->getOperatorType() != ITM_NOTCOVERED //old stuff
          !outputFromChild.contains(valId.getItemExpr()->child(i)->getValueId()))
      {
        children += valId.getItemExpr()->child(i)->getValueId();
      }
    }
  }
  
  if (NOT children.isEmpty())
  {
    computeHistoryRows(children, 
                       computedHistoryRows, 
                       unableToCalculate, 
                       unboundedFollowing, 
                       minFollowingRows,
                       outputFromChild);  
  }
} // PhysSequence::computeHistoryRows
Exemplo n.º 10
0
void PhysSequence::computeReadNReturnItems( ValueId topSeqVid,
                                            ValueId vid,
                                            const ValueIdSet &outputFromChild,
                                            CollHeap *wHeap)
{
  ItemExpr * itmExpr = vid.getItemExpr();


  if (outputFromChild.contains(vid)) 
  {
    return;
  }
  //test if itm_minus and then if negative offset ....
  if ( itmExpr->getOperatorType() == ITM_OFFSET &&
      ((ItmSeqOffset *)itmExpr)->getOffsetConstantValue() < 0)
  {
    readSeqFunctions() -= topSeqVid;
    returnSeqFunctions() += topSeqVid;

    readSeqFunctions() += itmExpr->child(0)->castToItemExpr()->getValueId();
    return;
  }
  
  if (itmExpr->getOperatorType() == ITM_MINUS)
  {
    ItemExpr * chld0  = itmExpr->child(0)->castToItemExpr();
    if ( chld0->getOperatorType() == ITM_OFFSET &&
        ((ItmSeqOffset *)chld0)->getOffsetConstantValue() <0)
    {
      readSeqFunctions() -= topSeqVid;
      returnSeqFunctions() += topSeqVid;

      readSeqFunctions() += chld0->child(0)->castToItemExpr()->getValueId();

      ItemExpr * chld1  = itmExpr->child(1)->castToItemExpr();
      if (chld1->getOperatorType() == ITM_OFFSET &&
          ((ItmSeqOffset *)chld1)->getOffsetConstantValue() < 0)
      {
        readSeqFunctions() += chld1->child(0)->castToItemExpr()->getValueId();
      }
      else
      {
        readSeqFunctions() += chld1->getValueId();
      }
      return;
    }
    
  }
  
  
  if (itmExpr->getOperatorType() == ITM_OLAP_MIN || 
           itmExpr->getOperatorType() == ITM_OLAP_MAX) 
  { 
    ItmSeqOlapFunction * olap = (ItmSeqOlapFunction *)itmExpr;
    if (olap->getframeEnd()>0)
    {
      readSeqFunctions() -= topSeqVid;
      returnSeqFunctions() += topSeqVid;

      ItemExpr *newChild = new(wHeap) Convert (itmExpr->child(0)->castToItemExpr());
      newChild->synthTypeAndValueId(TRUE);

      itmExpr->child(0) = newChild;

      readSeqFunctions() += newChild->getValueId();
      return;
    }
  }
  
  if (itmExpr->getOperatorType() == ITM_SCALAR_MIN || 
           itmExpr->getOperatorType() == ITM_SCALAR_MAX) 
  {
    ItemExpr * chld0  = itmExpr->child(0)->castToItemExpr();
    ItemExpr * chld1  = itmExpr->child(1)->castToItemExpr();
    if ((chld0->getOperatorType() == ITM_OLAP_MIN && chld1->getOperatorType() == ITM_OLAP_MIN )|| 
        (chld0->getOperatorType() == ITM_OLAP_MAX && chld1->getOperatorType() == ITM_OLAP_MAX ))
    {
      ItmSeqOlapFunction * olap0 = (ItmSeqOlapFunction *)chld0;
      ItmSeqOlapFunction * olap1 = (ItmSeqOlapFunction *)chld1;
      if ( olap1->getframeEnd()>0)
      { 
        CMPASSERT(olap0->getframeEnd()==0);

        readSeqFunctions() -= topSeqVid;
        returnSeqFunctions() += topSeqVid;
        readSeqFunctions() += olap0->getValueId();
        
        ItemExpr *newChild = new(wHeap) Convert (olap1->child(0)->castToItemExpr());
        newChild->synthTypeAndValueId(TRUE);

        olap1->child(0) = newChild;

        readSeqFunctions() += newChild->getValueId();
      }
      else
      {
        CMPASSERT(olap1->getframeEnd()==0);

        readSeqFunctions() -= topSeqVid;
        returnSeqFunctions() += topSeqVid;
        readSeqFunctions() += olap1->getValueId();

        ItemExpr *newChild = new(wHeap) Convert (olap0->child(0)->castToItemExpr());
        newChild->synthTypeAndValueId(TRUE);

        olap0->child(0) = newChild;

        readSeqFunctions() += newChild->getValueId();
      }
      return;
    }
  }

  for (Int32 i= 0 ; i < itmExpr->getArity(); i++)
  {
    ItemExpr * chld= itmExpr->child(i);
    computeReadNReturnItems(topSeqVid,
                            chld->getValueId(),
                            outputFromChild,
                            wHeap);
  }
}//void PhysSequence::computeReadNReturnItems(ItemExpr * other)
Exemplo n.º 11
0
// remove an element that is given by its value
ItemExpr * ItemExprTreeAsList::remove(ItemExpr *treeToRemove)
{
  ItemExpr *andNodePtr  = treePtr_->getPtr();
  ItemExpr *predecessor = NULL;
  NABoolean found       = FALSE;

  // assume the predicate is represented in right-linear
  // form:
  //
  //         op
  //        /   \
  //	   A    op
  //	       /   \
  //	      B     ...
  //
  // and search for the <op> node that is directly above the
  // predicate that we want to remove.

  if (shape_ != RIGHT_LINEAR_TREE)
    ABORT("delete is supported for right linear trees only");

  // is the node to delete the only node?
  if (treeToRemove == andNodePtr)
    {
      found = TRUE;
      delete andNodePtr;
      *treePtr_ = NULL;
    }
  else
    // traverse the backbone looking for "treeToRemove"
    while (andNodePtr != NULL AND
	   andNodePtr->getOperatorType() == operator_ AND
	   andNodePtr->getArity() == 2 AND
	   NOT found)
      {
	// did we find the right node?
	if (andNodePtr->child(0).getPtr() == treeToRemove)
	  {
	    found = TRUE;
	    
	    // take "andNode" out of the original tree
	    if (predecessor != NULL)
	      {
		predecessor->child(1) = andNodePtr->child(1);
	      }
	    else
	      *treePtr_ = andNodePtr->child(1);
	    
	    // set all children of "andNode" to NULL, then delete it
	    andNodePtr->child(0) = NULL;
	    andNodePtr->child(1) = NULL;
	    delete andNodePtr;
	    andNodePtr = NULL;
	  }
	else
	  {
	    predecessor = andNodePtr;
	    andNodePtr = andNodePtr->child(1);
	  }
      }
  
  if (found)
    return treeToRemove;
  else
    return NULL;

}
Exemplo n.º 12
0
// insert a new entry.
// The new entry is created at the end of the current tree.
void ItemExprTreeAsList::insert(ItemExpr *treeToInsert)
{
  if (treePtr_->getPtr() == NULL)
    {
      *treePtr_ = treeToInsert;
    }
  else
    {
      if (shape_ == RIGHT_LINEAR_TREE)
	{
	  switch (operator_)
	    {
	    case ITM_AND:
	      *treePtr_ = new(CmpCommon::statementHeap()) 
		BiLogic(operator_,
			treeToInsert,
			treePtr_->getPtr());
	      break;

	    case ITM_ITEM_LIST:
	      {
		ItemExpr *aNode = treePtr_->getPtr();
		ItemExpr *pNode = treePtr_->getPtr();
		if (aNode->getOperatorType() != operator_ AND
		    aNode->getArity() < 2)
		  {
		    // case of current number of entries equal to 1.
		    *treePtr_ = new(CmpCommon::statementHeap())
		      ItemList(treePtr_->getPtr(),
			       treeToInsert);
		  }
		else
		  {
		    // current number of entries > 1
		    while (aNode != NULL)
		      {
			if (aNode->getOperatorType() == operator_ AND
			    aNode->getArity() >= 2)
			  {
			    if (shape_ == RIGHT_LINEAR_TREE)
			      {
				pNode = aNode;
				aNode = aNode->child(1);
			      }
			    else
			      ABORT("can't do other than right-linear trees");
			  }
			else
			  aNode = NULL;
		      }
		    
		    pNode->child(1) = new(CmpCommon::statementHeap())
		      ItemList(pNode->child(1),
			       treeToInsert);
		    
		  }
	      }
	      
	      break;

	    default:
	      ABORT("Can't do backbones with this node type");
	    }
	}
      else
	ABORT("can only insert into right-linear trees");
    }
}
//----------------------------------------------------------------------------
// Transform each aggregate in the MAV select list, to use the @OP column in
// order to calculate deleted rows correctly:
// COUNT(*) => SUM(@OP)
// COUNT(a) => SUM(IF (a IS NULL) THEN 0 ELSE @OP) 
// SUM(a)   => SUM(a * @OP)
// MIN(a) & MAX(a) => Special treatment (see handleDeltaMinMaxColumns()).
// AVG, STDDEV and VARIANCE are derived from other COUNT and SUM columns. 
// They are removed from this select list to avoid divide by zero problems
// in case COUNT=0.
void MavRelRootBuilder::fixDeltaColumns(RelExpr   *mvSelectTree, 
					NABoolean  canSkipMinMax,
				        NABoolean  wasFullDE)
{
  // Get the MAV select list from the mvSelectTree.
  CMPASSERT(mvSelectTree->getOperatorType() == REL_ROOT);
  RelRoot *mavSelectRoot = (RelRoot *)mvSelectTree;

  ItemExprList mavSelectList(mavSelectRoot->removeCompExprTree(), heap_);
  ItemExprList newSelectList(heap_);

  const NAString& opName = MavBuilder::getVirtualOpColumnName();

  for (CollIndex i=0; i<mavSelectList.entries(); i++)
  {
    ItemExpr *selectListExpr = mavSelectList[i];

    CMPASSERT(selectListExpr->getOperatorType() == ITM_RENAME_COL);
    const NAString& colName = 
      ((RenameCol*)selectListExpr)->getNewColRefName()->getColName();
    ItemExpr *aggregateExpr = selectListExpr;
    while ((aggregateExpr->getOperatorType() == ITM_RENAME_COL) ||
           (aggregateExpr->getOperatorType() == ITM_CAST))
      aggregateExpr = aggregateExpr->child(0);

    // Assuming all aggregates are top-most functions as explained in the 
    // MV external spec.
    ItemExpr *aggregateOperand = aggregateExpr->child(0);
    ItemExpr *newExpr   = NULL;

    if (!aggregateExpr->containsAnAggregate())
    {
      // Non-aggregate columns (group-by cols) are added unchanged.
    }
    else
      switch (aggregateExpr->getOperatorType())
      {
	case ITM_COUNT_NONULL:
	  // COUNT(a) => SUM(IF (a IS NULL) THEN 0 ELSE @OP) 
	  newExpr = new(heap_) 
	    Aggregate(ITM_SUM, new(heap_) 
	      Case(NULL, new(heap_)
		IfThenElse (new(heap_) UnLogic(ITM_IS_NULL, aggregateOperand),
    			    new(heap_) SystemLiteral(0),
			    new(heap_) ColReference(new(heap_) 
			      ColRefName(opName)))));
	  selectListExpr->child(0) = newExpr;
	  break;

	case ITM_COUNT:
	  // COUNT(*) => SUM(@OP)
	  newExpr = new(heap_) 
	    Aggregate(ITM_SUM, 
    		      new(heap_) ColReference(new(heap_) ColRefName(opName)));
	  selectListExpr->child(0) = newExpr;
	  break;

	case ITM_SUM:
	  // SUM(a) => SUM(a * @OP)
	  newExpr = new(heap_)
	    BiArith(ITM_TIMES,
		    aggregateOperand,
		    new(heap_) ColReference(new(heap_) ColRefName(opName)));
	  aggregateExpr->child(0) = newExpr;
	  break;

	case ITM_MIN:
	case ITM_MAX:
	  // Handle Min/Max if not all deltas are INSERT ONLY.
	  if (!canSkipMinMax)
	    handleDeltaMinMaxColumns(aggregateExpr, colName, newSelectList, wasFullDE);
	  // Add the SYS_DELTA Min/Max aggregate as is.
	  break;

	case ITM_AVG:
	case ITM_DIVIDE:
	case ITM_VARIANCE:
	case ITM_STDDEV:
	  // Remove these expressions from the select list.
	  selectListExpr = NULL;
	  break;

	default:
	  // A new type of aggregate?
	  CMPASSERT(FALSE);
	  break;
      }

    if (selectListExpr!=NULL)
      newSelectList.insert(selectListExpr);
  }

  ItemExpr *selList = newSelectList.convertToItemExpr();
  mavSelectRoot->addCompExprTree(selList);

  mavSelectList.clear(); // Don't delete all the entries from the Dtor.
}  // MavRelRootBuilder::fixDeltaColumns()