public static Predicate Or(params FNode[] Nodes)
{
FNodeResult or = new FNodeResult(null, new AndMany());
or.AddChildren(Nodes);
return new Predicate(or);
}
public static Predicate And(params FNode[] Nodes)
{
FNodeResult and = new FNodeResult(null, new AndMany());
and.AddChildren(Nodes);
return new Predicate(and);
}
public static FNode Multiply(FNode Left, FNode Right)
{
FNode t = new FNodeResult(Left.ParentNode, CellFunctionFactory.LookUp(FunctionNames.OP_MUL));
t.AddChildren(Left, Right);
return t;
}
// Main Join Functions //
/// <summary>
/// Allows the user to perform a join based on the equality predicate AND each predicate link via 'AND'
/// </summary>
/// <param name="Output"></param>
/// <param name="JM"></param>
/// <param name="JA"></param>
/// <param name="T1"></param>
/// <param name="J1"></param>
/// <param name="T2"></param>
/// <param name="J2"></param>
/// <param name="CM"></param>
public static void Join(MergeMethod JM, MergeAlgorithm JA, RecordWriter Output, FNodeSet Fields, Predicate Where, DataSet Data1, DataSet Data2,
Key Equality1, Key Equality2, StaticRegister Memory1, StaticRegister Memory2)
{
// Do some checks first //
if (Where == null)
Where = Predicate.TrueForAll;
if (Equality1.Count != Equality2.Count)
throw new Exception("Both join keys must have the same length");
if (Equality1.Count == 0)
JA = MergeAlgorithm.NestedLoop;
// Nested loop; if the algorithm is nested loop and we have keys, we need to build a new where clause that has the equality predicates //
FNodeResult nl_node = new FNodeResult(null, new AndMany());
nl_node.AddChildNode(Where.Node.CloneOfMe());
for (int i = 0; i < Equality1.Count; i++)
{
FNodeFieldRef left = new FNodeFieldRef(null, Equality1[i], Data1.Columns.ColumnAffinity(Equality1[i]), Data1.Columns.ColumnSize(Equality1[i]), Memory1);
FNodeFieldRef right = new FNodeFieldRef(null, Equality2[i], Data2.Columns.ColumnAffinity(Equality2[i]), Data2.Columns.ColumnSize(Equality2[i]), Memory2);
FNodeResult eq = new FNodeResult(null, new CellBoolEQ());
eq.AddChildren(left, right);
nl_node.AddChildNode(eq);
}
Predicate nl_where = (Equality1.Count == 0 ? Where : new Predicate(nl_node));
// Switch //
switch (JA)
{
case MergeAlgorithm.SortMerge:
SortMerge(JM, Output, Fields, Where, Data1, Data2, Equality1, Equality2, Memory1, Memory2);
break;
case MergeAlgorithm.NestedLoop:
NestedLoop(JM, Output, Fields, nl_where, Data1, Data2, Memory1, Memory2);
break;
default:
HashTable(JM, Output, Fields, Where, Data1, Data2, Equality1, Equality2, Memory1, Memory2);
break;
}
}
public static FNode operator ^(FNode Left, FNode Right)
{
FNodeResult t = new FNodeResult(null, new CellFuncFVPower());
t.AddChildren(Left, Right);
return t;
}
public static FNode operator %(FNode Left, FNode Right)
{
FNodeResult t = new FNodeResult(null, new CellBinMod());
t.AddChildren(Left, Right);
return t;
}
