/// <summary>
/// Makes a copy of this SelectExpression.
/// </summary>
/// <param name="alias"> The alias. </param>
/// <returns>
/// A copy of this SelectExpression.
/// </returns>
public virtual SelectExpression Clone([CanBeNull] string alias = null)
{
var selectExpression
= new SelectExpression(_querySqlGeneratorFactory, _queryCompilationContext)
{
_limit = _limit,
_offset = _offset,
_isDistinct = _isDistinct,
_subqueryDepth = _subqueryDepth,
IsProjectStar = IsProjectStar,
Predicate = Predicate
};
if (alias != null)
{
selectExpression.Alias = _queryCompilationContext.CreateUniqueTableAlias(alias);
}
selectExpression._projection.AddRange(_projection);
selectExpression.AddTables(_tables);
selectExpression.AddToOrderBy(_orderBy);
return(selectExpression);
}
public virtual void AddTable([NotNull] TableExpressionBase tableExpression, bool createUniqueAlias = true)
{
Check.NotNull(tableExpression, nameof(tableExpression));
if (createUniqueAlias)
{
tableExpression.Alias = _queryCompilationContext.CreateUniqueTableAlias(tableExpression.Alias);
}
_tables.Add(tableExpression);
}
/// <summary>
/// Creates a new instance of SelectExpression.
/// </summary>
/// <param name="querySqlGeneratorFactory"> The query SQL generator factory. </param>
/// <param name="queryCompilationContext"> Context for the query compilation. </param>
/// <param name="alias"> The alias. </param>
public SelectExpression(
[NotNull] IQuerySqlGeneratorFactory querySqlGeneratorFactory,
[NotNull] RelationalQueryCompilationContext queryCompilationContext,
[NotNull] string alias)
: this(querySqlGeneratorFactory, queryCompilationContext)
{
Check.NotNull(alias, nameof(alias));
// When assigning alias to select expression make it unique
Alias = queryCompilationContext.CreateUniqueTableAlias(alias);
}
/// <summary>
/// Creates a new instance of SelectExpression.
/// </summary>
/// <param name="dependencies"> Parameter object containing dependencies for this service. </param>
/// <param name="queryCompilationContext"> Context for the query compilation. </param>
/// <param name="alias"> The alias. </param>
public SelectExpression(
[NotNull] SelectExpressionDependencies dependencies,
[NotNull] RelationalQueryCompilationContext queryCompilationContext,
[NotNull] string alias)
: this(dependencies, queryCompilationContext)
{
Check.NotNull(alias, nameof(alias));
// When assigning alias to select expression make it unique
Alias = queryCompilationContext.CreateUniqueTableAlias(alias);
}
/// <summary>
/// Creates a new instance of SelectExpression.
/// </summary>
/// <param name="dependencies"> Parameter object containing dependencies for this service. </param>
/// <param name="queryCompilationContext"> Context for the query compilation. </param>
/// <param name="alias"> The alias. </param>
public SelectExpression(
[NotNull] SelectExpressionDependencies dependencies,
[NotNull] RelationalQueryCompilationContext queryCompilationContext,
[NotNull] string alias)
: this(dependencies, queryCompilationContext)
{
Check.NotNull(alias, nameof(alias));
// When assigning alias to select expression make it unique
// ReSharper disable once VirtualMemberCallInConstructor
Alias = queryCompilationContext.CreateUniqueTableAlias(alias);
}
private IReadOnlyList <Func <QueryContext, TRelatedEntitiesLoader> > CreateRelatedEntitiesLoaders <TRelatedEntitiesLoader>(
IQuerySource querySource, IEnumerable <INavigation> navigationPath)
{
var relatedEntitiesLoaders = new List <Func <QueryContext, TRelatedEntitiesLoader> >();
var selectExpression
= _queryCompilationContext.FindSelectExpression(querySource);
var compositePredicateExpressionVisitor
= _compositePredicateExpressionVisitorFactory.Create();
var targetTableExpression
= selectExpression.GetTableForQuerySource(querySource);
var canProduceInnerJoin = true;
var navigationCount = 0;
foreach (var navigation in navigationPath)
{
var queryIndex = _queryIndexes[navigationCount];
navigationCount++;
var targetEntityType = navigation.GetTargetType();
var targetTableName = _relationalAnnotationProvider.For(targetEntityType).TableName;
var targetTableAlias
= _queryCompilationContext
.CreateUniqueTableAlias(targetTableName[0].ToString().ToLowerInvariant());
if (!navigation.IsCollection())
{
var joinedTableExpression
= new TableExpression(
targetTableName,
_relationalAnnotationProvider.For(targetEntityType).Schema,
targetTableAlias,
querySource);
var valueBufferOffset = selectExpression.Projection.Count;
canProduceInnerJoin
= canProduceInnerJoin &&
navigation.ForeignKey.IsRequired &&
navigation.IsDependentToPrincipal();
var joinExpression
= canProduceInnerJoin
? selectExpression.AddInnerJoin(joinedTableExpression)
: selectExpression.AddLeftOuterJoin(joinedTableExpression);
var oldPredicate = selectExpression.Predicate;
var materializer
= _materializerFactory
.CreateMaterializer(
targetEntityType,
selectExpression,
(p, se) => se.AddToProjection(
new AliasExpression(
new ColumnExpression(
_relationalAnnotationProvider.For(p).ColumnName,
p,
joinedTableExpression))) - valueBufferOffset,
querySource: null);
if (selectExpression.Predicate != oldPredicate)
{
selectExpression.Predicate
= compositePredicateExpressionVisitor
.Visit(selectExpression.Predicate);
var newJoinExpression = AdjustJoinExpression(selectExpression, joinExpression);
selectExpression.Predicate = oldPredicate;
selectExpression.RemoveTable(joinExpression);
selectExpression.AddTable(newJoinExpression, createUniqueAlias: false);
joinExpression = newJoinExpression;
}
joinExpression.Predicate
= BuildJoinEqualityExpression(
navigation,
navigation.IsDependentToPrincipal() ? targetTableExpression : joinExpression,
navigation.IsDependentToPrincipal() ? joinExpression : targetTableExpression,
querySource);
targetTableExpression = joinedTableExpression;
relatedEntitiesLoaders.Add(qc =>
(TRelatedEntitiesLoader)_queryCompilationContext.QueryMethodProvider
.CreateReferenceRelatedEntitiesLoaderMethod
.Invoke(
null,
new object[]
{
valueBufferOffset,
queryIndex,
materializer.Compile() // TODO: Used cached materializer?
}));
}
else
{
var principalTable
= selectExpression.Tables.Count == 1 &&
selectExpression.Tables
.OfType <SelectExpression>()
.Any(s => s.Tables.Any(t => t.QuerySource == querySource))
// true when select is wrapped e.g. when RowNumber paging is enabled
? selectExpression.Tables[0]
: selectExpression.Tables.Last(t => t.QuerySource == querySource);
var canGenerateExists
= (selectExpression.Predicate != null ||
selectExpression.Offset == null) &&
!IsOrderingOnNonPrincipalKeyProperties(
selectExpression.OrderBy,
navigation.ForeignKey.PrincipalKey.Properties);
foreach (var property in navigation.ForeignKey.PrincipalKey.Properties)
{
selectExpression
.AddToOrderBy(
_relationalAnnotationProvider.For(property).ColumnName,
property,
principalTable,
OrderingDirection.Asc);
}
var targetSelectExpression = _selectExpressionFactory.Create(_queryCompilationContext);
targetTableExpression
= new TableExpression(
targetTableName,
_relationalAnnotationProvider.For(targetEntityType).Schema,
targetTableAlias,
querySource);
targetSelectExpression.AddTable(targetTableExpression, createUniqueAlias: false);
var materializer
= _materializerFactory
.CreateMaterializer(
targetEntityType,
targetSelectExpression,
(p, se) => se.AddToProjection(
_relationalAnnotationProvider.For(p).ColumnName,
p,
querySource),
querySource: null);
if (canGenerateExists)
{
var subqueryExpression = selectExpression.Clone();
subqueryExpression.ClearProjection();
subqueryExpression.ClearOrderBy();
subqueryExpression.IsProjectStar = false;
var subqueryTable
= subqueryExpression.Tables.Count == 1 &&
subqueryExpression.Tables
.OfType <SelectExpression>()
.Any(s => s.Tables.Any(t => t.QuerySource == querySource))
// true when select is wrapped e.g. when RowNumber paging is enabled
? subqueryExpression.Tables[0]
: subqueryExpression.Tables.Last(t => t.QuerySource == querySource);
var existsPredicateExpression = new ExistsExpression(subqueryExpression);
AddToPredicate(targetSelectExpression, existsPredicateExpression);
AddToPredicate(subqueryExpression, BuildJoinEqualityExpression(navigation, targetTableExpression, subqueryTable, querySource));
subqueryExpression.Predicate
= compositePredicateExpressionVisitor
.Visit(subqueryExpression.Predicate);
var pkPropertiesToFkPropertiesMap = navigation.ForeignKey.PrincipalKey.Properties
.Zip(navigation.ForeignKey.Properties, (k, v) => new { PkProperty = k, FkProperty = v })
.ToDictionary(x => x.PkProperty, x => x.FkProperty);
foreach (var ordering in selectExpression.OrderBy)
{
// ReSharper disable once PossibleNullReferenceException
var principalKeyProperty = ((ordering.Expression as AliasExpression)?.Expression as ColumnExpression).Property;
var referencedForeignKeyProperty = pkPropertiesToFkPropertiesMap[principalKeyProperty];
targetSelectExpression
.AddToOrderBy(
_relationalAnnotationProvider.For(referencedForeignKeyProperty).ColumnName,
referencedForeignKeyProperty,
targetTableExpression,
ordering.OrderingDirection);
}
}
else
{
var innerJoinSelectExpression
= selectExpression.Clone(
selectExpression.OrderBy
.Select(o => o.Expression)
.Last(o => o.IsAliasWithColumnExpression())
.TryGetColumnExpression().TableAlias);
innerJoinSelectExpression.ClearProjection();
var innerJoinExpression = targetSelectExpression.AddInnerJoin(innerJoinSelectExpression);
LiftOrderBy(innerJoinSelectExpression, targetSelectExpression, innerJoinExpression);
innerJoinSelectExpression.IsDistinct = true;
innerJoinExpression.Predicate
= BuildJoinEqualityExpression(
navigation,
targetTableExpression,
innerJoinExpression,
querySource);
}
targetSelectExpression.Predicate
= compositePredicateExpressionVisitor
.Visit(targetSelectExpression.Predicate);
selectExpression = targetSelectExpression;
relatedEntitiesLoaders.Add(qc =>
(TRelatedEntitiesLoader)_queryCompilationContext.QueryMethodProvider
.CreateCollectionRelatedEntitiesLoaderMethod
.Invoke(
null,
new object[]
{
qc,
_shaperCommandContextFactory.Create(() =>
_querySqlGeneratorFactory.CreateDefault(targetSelectExpression)),
queryIndex,
materializer.Compile() // TODO: Used cached materializer?
}));
}
}
return(relatedEntitiesLoaders);
}