Skip to content

Commit

Permalink
Query: Improvements to Relational GroupBy translation for composition
Browse files Browse the repository at this point in the history
- Add support for translating OrderBy after GroupBy operator
- Add support for `HAVING` clause in SQL which would be generated when translating predicate after GroupByAggregate Resolves #10870
- Make sure client eval warning is not issued when translating GroupByAggregate Resolves #11157
- GroupBy Aggregate works when element/result selector is DTO instead of anonymous type Resolves #11176 (KeySelector has to be client evaluated)
- Make sure that SQL added to GROUP BY clause is not aliased Resolves #11218
- Translate GroupBy Constant/Parameter with aggregates Resolves #9969

Part of #10012
Part of #2341
  • Loading branch information
smitpatel committed Mar 14, 2018
1 parent 248ec65 commit 6cf774e
Show file tree
Hide file tree
Showing 21 changed files with 1,563 additions and 544 deletions.
Original file line number Diff line number Diff line change
Expand Up @@ -25,11 +25,9 @@ public class ResultTransformingExpressionVisitor<TResult> : ExpressionVisitorBas
/// directly from your code. This API may change or be removed in future releases.
/// </summary>
public ResultTransformingExpressionVisitor(
[NotNull] IQuerySource outerQuerySource,
[NotNull] RelationalQueryCompilationContext relationalQueryCompilationContext,
bool throwOnNullResult)
{
Check.NotNull(outerQuerySource, nameof(outerQuerySource));
Check.NotNull(relationalQueryCompilationContext, nameof(relationalQueryCompilationContext));

_relationalQueryCompilationContext = relationalQueryCompilationContext;
Expand Down

Large diffs are not rendered by default.

Original file line number Diff line number Diff line change
Expand Up @@ -147,7 +147,6 @@ protected override Expression VisitBinary(BinaryExpression expression)
switch (expression.NodeType)
{
case ExpressionType.Coalesce:
{
var left = Visit(expression.Left);
var right = Visit(expression.Right);

Expand All @@ -157,31 +156,25 @@ protected override Expression VisitBinary(BinaryExpression expression)
&& right.Type != typeof(Expression[])
? expression.Update(left, expression.Conversion, right)
: null;
}

case ExpressionType.Equal:
case ExpressionType.NotEqual:
{
var structuralComparisonExpression
= UnfoldStructuralComparison(
expression.NodeType,
ProcessComparisonExpression(expression));

return structuralComparisonExpression;
}

case ExpressionType.GreaterThan:
case ExpressionType.GreaterThanOrEqual:
case ExpressionType.LessThan:
case ExpressionType.LessThanOrEqual:
{
return ProcessComparisonExpression(expression);
}

case ExpressionType.AndAlso:
{
var left = Visit(expression.Left);
var right = Visit(expression.Right);
left = Visit(expression.Left);
right = Visit(expression.Right);

if (expression == _topLevelPredicate)
{
Expand Down Expand Up @@ -209,7 +202,6 @@ var structuralComparisonExpression
return left != null && right != null
? Expression.AndAlso(left, right)
: null;
}

case ExpressionType.OrElse:
case ExpressionType.Add:
Expand All @@ -219,7 +211,6 @@ var structuralComparisonExpression
case ExpressionType.Modulo:
case ExpressionType.And:
case ExpressionType.Or:
{
var leftExpression = Visit(expression.Left);
var rightExpression = Visit(expression.Right);

Expand All @@ -232,7 +223,6 @@ var structuralComparisonExpression
expression.IsLiftedToNull,
expression.Method)
: null;
}
}

return null;
Expand Down Expand Up @@ -721,11 +711,35 @@ var newMemberExpression

private Expression TryBindQuerySourcePropertyExpression(MemberExpression memberExpression)
{
if (memberExpression.Expression is QuerySourceReferenceExpression qsre)
if (!(memberExpression.Expression is QuerySourceReferenceExpression qsre))
{
// For memberExpression of form g.Key.Id
// We need SelectExpression for g & Member for Id (since we saved mappings)
if (memberExpression.Expression is MemberExpression innerMemberExpression
&& innerMemberExpression.Expression is QuerySourceReferenceExpression
&& innerMemberExpression.Expression.Type.IsGrouping()
&& innerMemberExpression.Member.Name == nameof(IGrouping<int, int>.Key))
{
qsre = (QuerySourceReferenceExpression)innerMemberExpression.Expression;
}
else
{
qsre = null;
}
}

if (qsre != null)
{
var selectExpression = _queryModelVisitor.TryGetQuery(qsre.ReferencedQuerySource);
var sql = _queryModelVisitor.TryGetQuery(qsre.ReferencedQuerySource)
?.GetProjectionForMemberInfo(memberExpression.Member);

return selectExpression?.GetProjectionForMemberInfo(memberExpression.Member);
if (_topLevelPredicate != null
&& sql is AliasExpression aliasExpression)
{
return aliasExpression.Expression;
}

return sql;
}

return null;
Expand Down Expand Up @@ -794,30 +808,27 @@ protected override Expression VisitUnary(UnaryExpression expression)
switch (expression.NodeType)
{
case ExpressionType.Negate:
{
var operand = Visit(expression.Operand);
if (operand != null)
{
return Expression.Negate(operand);
}

break;
}

case ExpressionType.Not:
{
var operand = Visit(expression.Operand);
operand = Visit(expression.Operand);
if (operand != null)
{
return Expression.Not(operand);
}

break;
}

case ExpressionType.Convert:
{
var isTopLevelProjection = _isTopLevelProjection;
_isTopLevelProjection = false;
var operand = Visit(expression.Operand);
operand = Visit(expression.Operand);
_isTopLevelProjection = isTopLevelProjection;

if (operand != null)
Expand All @@ -832,7 +843,7 @@ protected override Expression VisitUnary(UnaryExpression expression)
}

break;
}

}

return null;
Expand Down Expand Up @@ -939,20 +950,46 @@ var subQueryModelVisitor
= (RelationalQueryModelVisitor)_queryModelVisitor.QueryCompilationContext
.CreateQueryModelVisitor(_queryModelVisitor);

if (expression.QueryModel.MainFromClause.FromExpression is QuerySourceReferenceExpression groupQsre
&& groupQsre.Type.IsGrouping())
{
var targetExpression = _queryModelVisitor.QueryCompilationContext.QuerySourceMapping
.GetExpression(groupQsre.ReferencedQuerySource);

if (targetExpression.Type == typeof(ValueBuffer))
{
var outerSelectExpression = _targetSelectExpression.Clone();
subQueryModelVisitor.AddQuery(subQueryModel.MainFromClause, outerSelectExpression);

_queryModelVisitor.QueryCompilationContext.AddOrUpdateMapping(
groupQsre.ReferencedQuerySource,
Expression.Parameter(
typeof(IEnumerable<>).MakeGenericType(typeof(ValueBuffer))));

subQueryModelVisitor.VisitSubQueryModel(subQueryModel);

_queryModelVisitor.QueryCompilationContext.AddOrUpdateMapping(
groupQsre.ReferencedQuerySource,
targetExpression);

if (outerSelectExpression.Projection.Count == 1)
{
var projection = outerSelectExpression.Projection.Single();

return projection is AliasExpression aliasExpression
? aliasExpression.Expression
: projection;
}
}
}

var queriesProjectionCountMapping
= _queryModelVisitor.Queries
.ToDictionary(k => k, s => s.Projection.Count);

var queryModelMapping = new Dictionary<QueryModel, QueryModel>();
subQueryModel.PopulateQueryModelMapping(queryModelMapping);

var groupByTranslation = expression.QueryModel.MainFromClause.FromExpression.Type.IsGrouping();
if (groupByTranslation)
{
var outerSelectExpression = _targetSelectExpression.Clone();
subQueryModelVisitor.AddQuery(subQueryModel.MainFromClause, outerSelectExpression);
}

subQueryModelVisitor.VisitSubQueryModel(subQueryModel);

if (subQueryModelVisitor.IsLiftable)
Expand All @@ -968,12 +1005,6 @@ var queriesProjectionCountMapping

_queryModelVisitor.LiftInjectedParameters(subQueryModelVisitor);

if (groupByTranslation
&& selectExpression.Projection.Count == 1)
{
return selectExpression.Projection.Single();
}

return selectExpression;
}

Expand Down Expand Up @@ -1041,7 +1072,6 @@ protected override Expression VisitExtension(Expression expression)
switch (expression)
{
case StringCompareExpression stringCompare:
{
var newLeft = Visit(stringCompare.Left);
var newRight = Visit(stringCompare.Right);
if (newLeft == null
Expand All @@ -1054,9 +1084,8 @@ protected override Expression VisitExtension(Expression expression)
|| newRight != stringCompare.Right
? new StringCompareExpression(stringCompare.Operator, newLeft, newRight)
: expression;
}

case ExplicitCastExpression explicitCast:
{
var newOperand = Visit(explicitCast.Operand);
if (newOperand == null)
{
Expand All @@ -1066,9 +1095,8 @@ protected override Expression VisitExtension(Expression expression)
return newOperand != explicitCast.Operand
? new ExplicitCastExpression(newOperand, explicitCast.Type)
: expression;
}

case NullConditionalExpression nullConditionalExpression:
{
var newAccessOperation = Visit(nullConditionalExpression.AccessOperation);
if (newAccessOperation == null)
{
Expand All @@ -1081,17 +1109,15 @@ protected override Expression VisitExtension(Expression expression)
}

return new NullableExpression(newAccessOperation);
}

case NullSafeEqualExpression nullSafeEqualExpression:
{
var equalityExpression
= new NullCompensatedExpression(nullSafeEqualExpression.EqualExpression);

return Visit(equalityExpression);
}

case NullCompensatedExpression nullCompensatedExpression:
{
var newOperand = Visit(nullCompensatedExpression.Operand);
newOperand = Visit(nullCompensatedExpression.Operand);
if (newOperand == null)
{
return null;
Expand All @@ -1100,7 +1126,7 @@ var equalityExpression
return newOperand != nullCompensatedExpression.Operand
? new NullCompensatedExpression(newOperand)
: nullCompensatedExpression;
}

case DiscriminatorPredicateExpression discriminatorPredicateExpression:
return new DiscriminatorPredicateExpression(
base.VisitExtension(expression), discriminatorPredicateExpression.QuerySource);
Expand Down
28 changes: 25 additions & 3 deletions src/EFCore.Relational/Query/Expressions/SelectExpression.cs
Original file line number Diff line number Diff line change
Expand Up @@ -93,6 +93,14 @@ public SelectExpression(
/// </value>
public virtual Expression Predicate { get; [param: CanBeNull] set; }

/// <summary>
/// Gets or sets the predicate corresponding to the HAVING part of the SELECT expression.
/// </summary>
/// <value>
/// The predicate.
/// </value>
public virtual Expression Having { get; [param: CanBeNull] set; }

/// <summary>
/// Gets or sets the table to be used for star projection.
/// </summary>
Expand Down Expand Up @@ -302,7 +310,8 @@ public virtual bool IsIdentityQuery()
&& Offset == null
&& Projection.Count == 0
&& OrderBy.Count == 0
&& GroupBy.Count == 0
// GroupBy is intentionally ommitted because GroupBy does not require a pushdown.
//&& GroupBy.Count == 0
&& Tables.Count == 1;

/// <summary>
Expand Down Expand Up @@ -689,7 +698,10 @@ public virtual void SetProjectionExpression([NotNull] Expression expression)

private Expression CreateUniqueProjection(Expression expression, string newAlias = null)
{
var currentProjectionIndex = _projection.FindIndex(e => e.Equals(expression));
var currentProjectionIndex
= _projection.FindIndex(
e => ExpressionEqualityComparer.Instance.Equals(e, expression)
|| ExpressionEqualityComparer.Instance.Equals((e as AliasExpression)?.Expression, expression));

if (currentProjectionIndex != -1)
{
Expand Down Expand Up @@ -871,7 +883,14 @@ public virtual void AddToPredicate([NotNull] Expression predicate)
{
Check.NotNull(predicate, nameof(predicate));

Predicate = Predicate != null ? AndAlso(Predicate, predicate) : predicate;
if (_groupBy.Count == 0)
{
Predicate = Predicate != null ? AndAlso(Predicate, predicate) : predicate;
}
else
{
Having = Having != null ? AndAlso(Having, predicate) : predicate;
}
}

/// <summary>
Expand All @@ -882,6 +901,9 @@ public virtual void AddToGroupBy([NotNull] Expression[] groupingExpressions)
{
Check.NotNull(groupingExpressions, nameof(groupingExpressions));

// Skip/Take will cause PushDown prior to calling this method so it is safe to clear ordering if any.
// Ordering before GroupBy Aggregate has no effect.
_orderBy.Clear();
_groupBy.AddRange(groupingExpressions);
}

Expand Down
Loading

0 comments on commit 6cf774e

Please sign in to comment.