Skip to content

Commit

Permalink
Query: Entity splitting support for regular entities (#28425)
Browse files Browse the repository at this point in the history 
Part of #620
  • Loading branch information
@smitpatel
smitpatel authored Jul 13, 2022
1 parent d4f0621 commit 43e0755
Show file tree
Hide file tree
Showing 22 changed files with 427 additions and 66 deletions.
2 changes: 1 addition & 1 deletion src/EFCore.Relational/Query/RelationalEntityShaperExpression.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -94,7 +94,7 @@ protected override LambdaExpression GenerateMaterializationCondition(IEntityType
return baseCondition;
}

var table = entityType.GetViewOrTableMappings().SingleOrDefault()?.Table
var table = entityType.GetViewOrTableMappings().SingleOrDefault(e => e.IsSplitEntityTypePrincipal ?? true)?.Table
?? entityType.GetDefaultMappings().Single().Table;
if (table.IsOptional(entityType))
{
Expand Down
2 changes: 1 addition & 1 deletion src/EFCore.Relational/Query/RelationalSqlTranslatingExpressionVisitor.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1320,7 +1320,7 @@ protected override Expression VisitUnary(UnaryExpression unaryExpression)
return propertyAccess;
}

var table = entityType.GetViewOrTableMappings().SingleOrDefault()?.Table
var table = entityType.GetViewOrTableMappings().SingleOrDefault(e => e.IsSplitEntityTypePrincipal ?? true)?.Table
?? entityType.GetDefaultMappings().Single().Table;
if (!table.IsOptional(entityType))
{
Expand Down
22 changes: 11 additions & 11 deletions src/EFCore.Relational/Query/SqlExpressions/SelectExpression.Helper.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -320,26 +320,26 @@ private sealed class ColumnExpressionFindingExpressionVisitor : ExpressionVisito
// Always skip the table of ColumnExpression since it will traverse into deeper subquery
return columnExpression;

case LeftJoinExpression leftJoinExpression:
var leftJoinTableAlias = leftJoinExpression.Table.Alias!;
case PredicateJoinExpressionBase predicateJoinExpressionBase:
var predicateJoinTableAlias = predicateJoinExpressionBase.Table.Alias!;
// Visiting the join predicate will add some columns for join table.
// But if all the referenced columns are in join predicate only then we can remove the join table.
// So if there are no referenced columns yet means there is still potential to remove this table,
// In such case we moved the columns encountered in join predicate to other dictionary and later merge
// if there are more references to the join table outside of join predicate.
// We currently do this only for LeftJoin since that is the only predicate join table we remove.
// We should also remove references to the outer if this column gets removed then that subquery can also remove projections
// But currently we only remove table for TPT scenario in which there are all table expressions which connects via joins.
var joinOnSameLevel = _columnReferenced!.ContainsKey(leftJoinTableAlias);
var noReferences = !joinOnSameLevel || _columnReferenced[leftJoinTableAlias] == null;
base.Visit(leftJoinExpression);
// But currently we only remove table for TPT & entity splitting scenario
// in which there are all table expressions which connects via joins.
var joinOnSameLevel = _columnReferenced!.ContainsKey(predicateJoinTableAlias);
var noReferences = !joinOnSameLevel || _columnReferenced[predicateJoinTableAlias] == null;
base.Visit(predicateJoinExpressionBase);
if (noReferences && joinOnSameLevel)
{
_columnsUsedInJoinCondition![leftJoinTableAlias] = _columnReferenced[leftJoinTableAlias];
_columnReferenced[leftJoinTableAlias] = null;
_columnsUsedInJoinCondition![predicateJoinTableAlias] = _columnReferenced[predicateJoinTableAlias];
_columnReferenced[predicateJoinTableAlias] = null;
}

return leftJoinExpression;
return predicateJoinExpressionBase;

default:
return base.Visit(expression);
Expand Down Expand Up @@ -930,7 +930,7 @@ private sealed class CloningExpressionVisitor : ExpressionVisitor
};
newSelectExpression._mutable = selectExpression._mutable;

newSelectExpression._tptLeftJoinTables.AddRange(selectExpression._tptLeftJoinTables);
newSelectExpression._removableJoinTables.AddRange(selectExpression._removableJoinTables);

foreach (var kvp in selectExpression._tpcDiscriminatorValues)
{
Expand Down
139 changes: 104 additions & 35 deletions src/EFCore.Relational/Query/SqlExpressions/SelectExpression.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -45,7 +45,7 @@ public sealed partial class SelectExpression : TableExpressionBase

private readonly List<(ColumnExpression Column, ValueComparer Comparer)> _identifier = new();
private readonly List<(ColumnExpression Column, ValueComparer Comparer)> _childIdentifiers = new();
private readonly List<int> _tptLeftJoinTables = new();
private readonly List<int> _removableJoinTables = new();
private readonly Dictionary<TpcTablesExpression, (ColumnExpression, List<string>)> _tpcDiscriminatorValues
= new(ReferenceEqualityComparer.Instance);

Expand Down Expand Up @@ -165,7 +165,7 @@ internal SelectExpression(IEntityType entityType, ISqlExpressionFactory sqlExpre
.Aggregate((l, r) => sqlExpressionFactory.AndAlso(l, r));

var joinExpression = new LeftJoinExpression(tableExpression, joinPredicate);
_tptLeftJoinTables.Add(_tables.Count);
_removableJoinTables.Add(_tables.Count);
AddTable(joinExpression, tableReferenceExpression);
}

Expand All @@ -187,7 +187,7 @@ internal SelectExpression(IEntityType entityType, ISqlExpressionFactory sqlExpre
if (entityTypes.Length == 1)
{
// For single entity case, we don't need discriminator.
var table = GetTableBase(entityTypes[0]);
var table = entityTypes[0].GetViewOrTableMappings().Single().Table;
var tableExpression = new TableExpression(table);

var tableReferenceExpression = new TableReferenceExpression(this, tableExpression.Alias!);
Expand All @@ -212,7 +212,7 @@ internal SelectExpression(IEntityType entityType, ISqlExpressionFactory sqlExpre
}
else
{
var tables = entityTypes.Select(e => GetTableBase(e)).ToArray();
var tables = entityTypes.Select(e => e.GetViewOrTableMappings().Single().Table).ToArray();
var properties = GetAllPropertiesInHierarchy(entityType).ToArray();
var propertyNamesMap = new Dictionary<IProperty, string>();
for (var i = 0; i < entityTypes.Length; i++)
Expand Down Expand Up @@ -314,47 +314,106 @@ internal SelectExpression(IEntityType entityType, ISqlExpressionFactory sqlExpre
default:
{
// Also covers TPH
ITableBase table;
TableExpressionBase tableExpression;
if (entityType.GetFunctionMappings().SingleOrDefault(e => e.IsDefaultFunctionMapping) is IFunctionMapping functionMapping)
{
var storeFunction = functionMapping.Table;

table = storeFunction;
tableExpression = new TableValuedFunctionExpression((IStoreFunction)storeFunction, Array.Empty<SqlExpression>());
GenerateNonHierarchyNonSplittingEntityType(
storeFunction, new TableValuedFunctionExpression((IStoreFunction)storeFunction, Array.Empty<SqlExpression>()));
}
else
{
table = GetTableBase(entityType);
tableExpression = new TableExpression(table);
}
var mappings = entityType.GetViewOrTableMappings().ToList();
if (mappings.Count == 1)
{
var table = mappings[0].Table;

var tableReferenceExpression = new TableReferenceExpression(this, tableExpression.Alias!);
AddTable(tableExpression, tableReferenceExpression);
GenerateNonHierarchyNonSplittingEntityType(table, new TableExpression(table));
}
else
{
// entity splitting
var keyProperties = entityType.FindPrimaryKey()!.Properties;
List<ColumnExpression> joinColumns = default!;
var columns = new Dictionary<IProperty, ColumnExpression>();
var tableReferenceExpressionMap = new Dictionary<ITableBase, TableReferenceExpression>();
foreach (var mapping in mappings)
{
var table = mapping.Table;
var tableExpression = new TableExpression(table);
var tableReferenceExpression = new TableReferenceExpression(this, tableExpression.Alias);
tableReferenceExpressionMap[table] = tableReferenceExpression;

var propertyExpressions = new Dictionary<IProperty, ColumnExpression>();
foreach (var property in GetAllPropertiesInHierarchy(entityType))
{
propertyExpressions[property] = CreateColumnExpression(property, table, tableReferenceExpression, nullable: false);
}
if (_tables.Count == 0)
{
AddTable(tableExpression, tableReferenceExpression);
joinColumns = new List<ColumnExpression>();
foreach (var property in keyProperties)
{
var columnExpression = CreateColumnExpression(property, table, tableReferenceExpression, nullable: false);
columns[property] = columnExpression;
joinColumns.Add(columnExpression);
_identifier.Add((columnExpression, property.GetKeyValueComparer()));
}
}
else
{
var innerColumns = keyProperties.Select(
p => CreateColumnExpression(p, table, tableReferenceExpression, nullable: false));

var entityProjection = new EntityProjectionExpression(entityType, propertyExpressions);
_projectionMapping[new ProjectionMember()] = entityProjection;
var joinPredicate = joinColumns.Zip(innerColumns, (l, r) => sqlExpressionFactory.Equal(l, r))
.Aggregate((l, r) => sqlExpressionFactory.AndAlso(l, r));

var primaryKey = entityType.FindPrimaryKey();
if (primaryKey != null)
{
foreach (var property in primaryKey.Properties)
{
_identifier.Add((propertyExpressions[property], property.GetKeyValueComparer()));
var joinExpression = new InnerJoinExpression(tableExpression, joinPredicate);
_removableJoinTables.Add(_tables.Count);
AddTable(joinExpression, tableReferenceExpression);
}
}

foreach (var property in entityType.GetProperties())
{
if (property.IsPrimaryKey())
{
continue;
}

var columnBase = mappings.Select(e => e.Table.FindColumn(property)).First(e => e != null)!;
columns[property] = CreateColumnExpression(
property, columnBase, tableReferenceExpressionMap[columnBase.Table], nullable: false);
}

var entityProjection = new EntityProjectionExpression(entityType, columns);
_projectionMapping[new ProjectionMember()] = entityProjection;
}
}
}

break;
}

static ITableBase GetTableBase(IEntityType entityType) => entityType.GetViewOrTableMappings().Single().Table;
void GenerateNonHierarchyNonSplittingEntityType(ITableBase table, TableExpressionBase tableExpression)
{
var tableReferenceExpression = new TableReferenceExpression(this, tableExpression.Alias!);
AddTable(tableExpression, tableReferenceExpression);

var propertyExpressions = new Dictionary<IProperty, ColumnExpression>();
foreach (var property in GetAllPropertiesInHierarchy(entityType))
{
propertyExpressions[property] = CreateColumnExpression(property, table, tableReferenceExpression, nullable: false);
}

var entityProjection = new EntityProjectionExpression(entityType, propertyExpressions);
_projectionMapping[new ProjectionMember()] = entityProjection;

var primaryKey = entityType.FindPrimaryKey();
if (primaryKey != null)
{
foreach (var property in primaryKey.Properties)
{
_identifier.Add((propertyExpressions[property], property.GetKeyValueComparer()));
}
}
}

static ITableBase GetTableBaseFiltered(IEntityType entityType, List<ITableBase> existingTables)
=> entityType.GetViewOrTableMappings().Single(m => !existingTables.Contains(m.Table)).Table;
Expand Down Expand Up @@ -1713,8 +1772,8 @@ private void ApplySetOperation(SetOperationType setOperationType, SelectExpressi
_projectionMapping.Clear();
select1._identifier.AddRange(_identifier);
_identifier.Clear();
select1._tptLeftJoinTables.AddRange(_tptLeftJoinTables);
_tptLeftJoinTables.Clear();
select1._removableJoinTables.AddRange(_removableJoinTables);
_removableJoinTables.Clear();
foreach (var kvp in _tpcDiscriminatorValues)
{
select1._tpcDiscriminatorValues[kvp.Key] = kvp.Value;
Expand Down Expand Up @@ -2902,8 +2961,8 @@ private SqlRemappingVisitor PushdownIntoSubqueryInternal()
Having = null;
Offset = null;
Limit = null;
subquery._tptLeftJoinTables.AddRange(_tptLeftJoinTables);
_tptLeftJoinTables.Clear();
subquery._removableJoinTables.AddRange(_removableJoinTables);
_removableJoinTables.Clear();
foreach (var kvp in _tpcDiscriminatorValues)
{
subquery._tpcDiscriminatorValues[kvp.Key] = kvp.Value;
Expand Down Expand Up @@ -3213,14 +3272,17 @@ private SelectExpression Prune(IReadOnlyCollection<string>? referencedColumns)
var columnExpressionFindingExpressionVisitor = new ColumnExpressionFindingExpressionVisitor();
var columnsMap = columnExpressionFindingExpressionVisitor.FindColumns(this);
var removedTableCount = 0;
// Start at 1 because we don't drop main table.
// Dropping main table is more complex because other tables need to unwrap joins to be main
for (var i = 0; i < _tables.Count; i++)
{
var table = _tables[i];
var tableAlias = GetAliasFromTableExpressionBase(table);
if (columnsMap[tableAlias] == null
&& (table is LeftJoinExpression
|| table is OuterApplyExpression)
&& _tptLeftJoinTables?.Contains(i + removedTableCount) == true)
|| table is OuterApplyExpression
|| table is InnerJoinExpression) // This is only valid for removable join table which are from entity splitting
&& _removableJoinTables?.Contains(i + removedTableCount) == true)
{
_tables.RemoveAt(i);
_tableReferences.RemoveAt(i);
Expand Down Expand Up @@ -3341,7 +3403,14 @@ private static ConcreteColumnExpression CreateColumnExpression(
ITableBase table,
TableReferenceExpression tableExpression,
bool nullable)
=> new(property, table.FindColumn(property)!, tableExpression, nullable);
=> CreateColumnExpression(property, table.FindColumn(property)!, tableExpression, nullable);

private static ConcreteColumnExpression CreateColumnExpression(
IProperty property,
IColumnBase columnBase,
TableReferenceExpression tableExpression,
bool nullable)
=> new(property, columnBase, tableExpression, nullable);

private ConcreteColumnExpression GenerateOuterColumn(
TableReferenceExpression tableReferenceExpression,
Expand Down Expand Up @@ -3578,7 +3647,7 @@ protected override Expression VisitChildren(ExpressionVisitor visitor)
_usedAliases = _usedAliases,
};
newSelectExpression._mutable = false;
newSelectExpression._tptLeftJoinTables.AddRange(_tptLeftJoinTables);
newSelectExpression._removableJoinTables.AddRange(_removableJoinTables);
foreach (var kvp in newTpcDiscriminatorValues)
{
newSelectExpression._tpcDiscriminatorValues[kvp.Key] = kvp.Value;
Expand Down
4 changes: 2 additions & 2 deletions test/EFCore.Relational.Specification.Tests/EntitySplittingTestBase.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -11,10 +11,10 @@ protected EntitySplittingTestBase(ITestOutputHelper testOutputHelper)
//TestSqlLoggerFactory.SetTestOutputHelper(testOutputHelper);
}

[ConditionalFact(Skip = "Entity splitting query Issue #620")]
[ConditionalFact]
public virtual async Task Can_roundtrip()
{
await InitializeAsync(OnModelCreating, sensitiveLogEnabled: false);
await InitializeAsync(OnModelCreating, sensitiveLogEnabled: true);

await using (var context = CreateContext())
{
Expand Down
Loading

0 comments on commit 43e0755

Please sign in to comment.