internal CellQuery(
List <ProjectedSlot> slots,
BoolExpression whereClause,
MemberPath rootMember,
CellQuery.SelectDistinct eliminateDuplicates)
: this(slots.ToArray(), whereClause, new List <BoolExpression>(), eliminateDuplicates, rootMember)
{
}
internal CellQuery(CellQuery source)
{
this.m_basicCellRelation = source.m_basicCellRelation;
this.m_boolExprs = source.m_boolExprs;
this.m_selectDistinct = source.m_selectDistinct;
this.m_extentMemberPath = source.m_extentMemberPath;
this.m_originalWhereClause = source.m_originalWhereClause;
this.m_projectedSlots = source.m_projectedSlots;
this.m_whereClause = source.m_whereClause;
}
// effects: Given two duplicate eliination choices, returns an OR of them
static private CellQuery.SelectDistinct MergeDupl(CellQuery.SelectDistinct d1, CellQuery.SelectDistinct d2)
{
if (d1 == CellQuery.SelectDistinct.Yes || d2 == CellQuery.SelectDistinct.Yes)
{
return(CellQuery.SelectDistinct.Yes);
}
else
{
return(CellQuery.SelectDistinct.No);
}
}
/// <summary>
/// Creates an cql block representing the <paramref name="extent"/> (the FROM part).
/// SELECT is given by <paramref name="slots"/>, WHERE by <paramref name="whereClause"/> and AS by <paramref name="blockAliasNum"/>.
/// </summary>
internal ExtentCqlBlock(EntitySetBase extent,
CellQuery.SelectDistinct selectDistinct,
SlotInfo[] slots,
BoolExpression whereClause,
CqlIdentifiers identifiers,
int blockAliasNum)
: base(slots, EmptyChildren, whereClause, identifiers, blockAliasNum)
{
m_extent = extent;
m_nodeTableAlias = identifiers.GetBlockAlias();
m_selectDistinct = selectDistinct;
}
internal CellQuery(
ProjectedSlot[] projectedSlots,
BoolExpression whereClause,
List <BoolExpression> boolExprs,
CellQuery.SelectDistinct elimDupl,
MemberPath rootMember)
{
this.m_boolExprs = boolExprs;
this.m_projectedSlots = projectedSlots;
this.m_whereClause = whereClause;
this.m_originalWhereClause = whereClause;
this.m_selectDistinct = elimDupl;
this.m_extentMemberPath = rootMember;
}
// effects: Merges query2 with this according to the TM/SP rules for opType and
// returns the merged result. canBooleansOverlap indicates whether the bools in this and query2 can overlap, i.e.
// the same cells may have contributed to query2 and this earlier in the merge process
internal bool TryMergeTwoCellQueries(CellQuery query1, CellQuery query2, CellTreeOpType opType,
MemberDomainMap memberDomainMap, out CellQuery mergedQuery)
{
mergedQuery = null;
// Initialize g1 and g2 according to the TM/SP rules for IJ, LOJ, Union, FOJ cases
BoolExpression g1 = null;
BoolExpression g2 = null;
switch (opType)
{
case CellTreeOpType.IJ:
break;
case CellTreeOpType.LOJ:
case CellTreeOpType.LASJ:
g2 = BoolExpression.True;
break;
case CellTreeOpType.FOJ:
case CellTreeOpType.Union:
g1 = BoolExpression.True;
g2 = BoolExpression.True;
break;
default:
Debug.Fail("Unsupported operator");
break;
}
Dictionary <MemberPath, MemberPath> remap =
new Dictionary <MemberPath, MemberPath>(MemberPath.EqualityComparer);
//Continue merging only if both queries are over the same source
MemberPath newRoot;
if (!query1.Extent.Equals(query2.Extent))
{ // could not merge
return(false);
}
else
{
newRoot = query1.SourceExtentMemberPath;
}
// Conjuncts for ANDing with the previous whereClauses
BoolExpression conjunct1 = BoolExpression.True;
BoolExpression conjunct2 = BoolExpression.True;
BoolExpression whereClause = null;
switch (opType)
{
case CellTreeOpType.IJ:
// Project[D1, D2, A, B, C] Select[cond1 and cond2] (T)
// We simply merge the two lists of booleans -- no conjuct is added
// conjunct1 and conjunct2 don't change
// query1.WhereCaluse AND query2.WhereCaluse
Debug.Assert(g1 == null && g2 == null, "IJ does not affect g1 and g2");
whereClause = BoolExpression.CreateAnd(query1.WhereClause, query2.WhereClause);
break;
case CellTreeOpType.LOJ:
// conjunct1 does not change since D1 remains as is
// Project[D1, (expr2 and cond2 and G2) as D2, A, B, C] Select[cond1] (T)
// D1 does not change. New d2 is the list of booleans expressions
// for query2 ANDed with g2 AND query2.WhereClause
Debug.Assert(g1 == null, "LOJ does not affect g1");
conjunct2 = BoolExpression.CreateAnd(query2.WhereClause, g2);
// Just query1's whereclause
whereClause = query1.WhereClause;
break;
case CellTreeOpType.FOJ:
case CellTreeOpType.Union:
// Project[(expr1 and cond1 and G1) as D1, (expr2 and cond2 and G2) as D2, A, B, C] Select[cond1] (T)
// New D1 is a list -- newD1 = D1 AND query1.WhereClause AND g1
// New D1 is a list -- newD2 = D2 AND query2.WhereClause AND g2
conjunct1 = BoolExpression.CreateAnd(query1.WhereClause, g1);
conjunct2 = BoolExpression.CreateAnd(query2.WhereClause, g2);
// The new whereClause -- g1 AND query1.WhereCaluse OR g2 AND query2.WhereClause
whereClause = BoolExpression.CreateOr(BoolExpression.CreateAnd(query1.WhereClause, g1),
BoolExpression.CreateAnd(query2.WhereClause, g2));
break;
case CellTreeOpType.LASJ:
// conjunct1 does not change since D1 remains as is
// Project[D1, (expr2 and cond2 and G2) as D2, A, B, C] Select[cond1] (T)
// D1 does not change. New d2 is the list of booleans expressions
// for query2 ANDed with g2 AND NOT query2.WhereClause
Debug.Assert(g1 == null, "LASJ does not affect g1");
conjunct2 = BoolExpression.CreateAnd(query2.WhereClause, g2);
whereClause = BoolExpression.CreateAnd(query1.WhereClause, BoolExpression.CreateNot(conjunct2));
break;
default:
Debug.Fail("Unsupported operator");
break;
}
// Create the various remapped parts for the cell query --
// boolean expressions, merged slots, whereclause, duplicate
// elimination, join tree
List <BoolExpression> boolExprs =
MergeBoolExpressions(query1, query2, conjunct1, conjunct2, opType);
//BoolExpression.RemapBools(boolExprs, remap);
ProjectedSlot[] mergedSlots;
if (false == ProjectedSlot.TryMergeRemapSlots(query1.ProjectedSlots, query2.ProjectedSlots, out mergedSlots))
{
// merging failed because two different right slots go to same left slot
return(false);
}
whereClause = whereClause.RemapBool(remap);
CellQuery.SelectDistinct elimDupl = MergeDupl(query1.SelectDistinctFlag, query2.SelectDistinctFlag);
whereClause.ExpensiveSimplify();
mergedQuery = new CellQuery(mergedSlots, whereClause,
boolExprs, elimDupl, newRoot);
return(true);
}
private static CellQuery.SelectDistinct MergeDupl(
CellQuery.SelectDistinct d1,
CellQuery.SelectDistinct d2)
{
return(d1 == CellQuery.SelectDistinct.Yes || d2 == CellQuery.SelectDistinct.Yes ? CellQuery.SelectDistinct.Yes : CellQuery.SelectDistinct.No);
}
internal static bool TryMergeTwoCellQueries(
CellQuery query1,
CellQuery query2,
CellTreeOpType opType,
out CellQuery mergedQuery)
{
mergedQuery = (CellQuery)null;
BoolExpression boolExpression1 = (BoolExpression)null;
BoolExpression boolExpression2 = (BoolExpression)null;
switch (opType)
{
case CellTreeOpType.Union:
case CellTreeOpType.FOJ:
boolExpression1 = BoolExpression.True;
boolExpression2 = BoolExpression.True;
break;
case CellTreeOpType.LOJ:
case CellTreeOpType.LASJ:
boolExpression2 = BoolExpression.True;
break;
}
Dictionary <MemberPath, MemberPath> remap = new Dictionary <MemberPath, MemberPath>(MemberPath.EqualityComparer);
if (!query1.Extent.Equals((object)query2.Extent))
{
return(false);
}
MemberPath extentMemberPath = query1.SourceExtentMemberPath;
BoolExpression and1 = BoolExpression.True;
BoolExpression and2 = BoolExpression.True;
BoolExpression boolExpression3 = (BoolExpression)null;
switch (opType)
{
case CellTreeOpType.Union:
case CellTreeOpType.FOJ:
and1 = BoolExpression.CreateAnd(query1.WhereClause, boolExpression1);
and2 = BoolExpression.CreateAnd(query2.WhereClause, boolExpression2);
boolExpression3 = BoolExpression.CreateOr(BoolExpression.CreateAnd(query1.WhereClause, boolExpression1), BoolExpression.CreateAnd(query2.WhereClause, boolExpression2));
break;
case CellTreeOpType.LOJ:
and2 = BoolExpression.CreateAnd(query2.WhereClause, boolExpression2);
boolExpression3 = query1.WhereClause;
break;
case CellTreeOpType.IJ:
boolExpression3 = BoolExpression.CreateAnd(query1.WhereClause, query2.WhereClause);
break;
case CellTreeOpType.LASJ:
and2 = BoolExpression.CreateAnd(query2.WhereClause, boolExpression2);
boolExpression3 = BoolExpression.CreateAnd(query1.WhereClause, BoolExpression.CreateNot(and2));
break;
}
List <BoolExpression> boolExprs = CellTreeSimplifier.MergeBoolExpressions(query1, query2, and1, and2, opType);
ProjectedSlot[] result;
if (!ProjectedSlot.TryMergeRemapSlots(query1.ProjectedSlots, query2.ProjectedSlots, out result))
{
return(false);
}
BoolExpression whereClause = boolExpression3.RemapBool(remap);
CellQuery.SelectDistinct elimDupl = CellTreeSimplifier.MergeDupl(query1.SelectDistinctFlag, query2.SelectDistinctFlag);
whereClause.ExpensiveSimplify();
mergedQuery = new CellQuery(result, whereClause, boolExprs, elimDupl, extentMemberPath);
return(true);
}
