Query: Add interface to get ITableBase for root level table sources

src/EFCore.Relational/Query/RelationalQueryableMethodTranslatingExpressionVisitor.cs

@@ -77,8 +77,7 @@ protected override Expression VisitExtension(Expression extensionExpression)
  _sqlExpressionFactory.Select(
  fromSqlQueryRootExpression.EntityType,
  new FromSqlExpression(
- fromSqlQueryRootExpression.EntityType.GetDefaultMappings().Single().Table.Name[..1]
- .ToLowerInvariant(),
+ fromSqlQueryRootExpression.EntityType.GetDefaultMappings().Single().Table,
  fromSqlQueryRootExpression.Sql,
  fromSqlQueryRootExpression.Argument)));
 
@@ -127,9 +126,14 @@ protected override Expression VisitExtension(Expression extensionExpression)
  when queryRootExpression.GetType() == typeof(QueryRootExpression)
  && queryRootExpression.EntityType.GetSqlQueryMappings().FirstOrDefault(m => m.IsDefaultSqlQueryMapping)?.SqlQuery is
  ISqlQuery sqlQuery:
- return Visit(
- new FromSqlQueryRootExpression(
- queryRootExpression.EntityType, sqlQuery.Sql, Expression.Constant(Array.Empty<object>(), typeof(object[]))));
+ return CreateShapedQueryExpression(
+ queryRootExpression.EntityType,
+ _sqlExpressionFactory.Select(
+ queryRootExpression.EntityType,
+ new FromSqlExpression(
+ queryRootExpression.EntityType.GetDefaultMappings().Single().Table,
+ sqlQuery.Sql,
+ Expression.Constant(Array.Empty<object>(), typeof(object[])))));
 
  case GroupByShaperExpression groupByShaperExpression:
  var groupShapedQueryExpression = groupByShaperExpression.GroupingEnumerable;

src/EFCore.Relational/Query/SqlExpressionFactory.cs

@@ -637,13 +637,7 @@ private void AddConditions(SelectExpression selectExpression, IEntityType entity
  return;
  }
 
- var table = selectExpression.Tables[0] switch
- {
- TableExpression te => te.Table,
- TableValuedFunctionExpression tvfe => tvfe.StoreFunction,
- _ => entityType.GetDefaultMappings().Single().Table,
- };
-
+ var table = ((ITableBasedExpression)selectExpression.Tables[0]).Table;
  if (table.IsOptional(entityType))
  {
  var entityProjectionExpression = GetMappedEntityProjectionExpression(selectExpression);

src/EFCore.Relational/Query/SqlExpressions/FromSqlExpression.cs

@@ -14,28 +14,40 @@ namespace Microsoft.EntityFrameworkCore.Query.SqlExpressions;
 /// not used in application code.
 /// </para>
 /// </summary>
-public class FromSqlExpression : TableExpressionBase, IClonableTableExpressionBase
+public class FromSqlExpression : TableExpressionBase, IClonableTableExpressionBase, ITableBasedExpression
 {
+ private readonly ITableBase _table;
+
  /// <summary>
  /// Creates a new instance of the <see cref="FromSqlExpression" /> class.
  /// </summary>
- /// <param name="alias">A string alias for the table source.</param>
+ /// <param name="defaultTableBase">A default table base associated with this table source.</param>
  /// <param name="sql">A user-provided custom SQL for the table source.</param>
  /// <param name="arguments">A user-provided parameters to pass to the custom SQL.</param>
- public FromSqlExpression(string alias, string sql, Expression arguments)
- : this(alias, sql, arguments, annotations: null)
+ public FromSqlExpression(ITableBase defaultTableBase, string sql, Expression arguments)
+ : this(defaultTableBase.Name[..1].ToLowerInvariant(), defaultTableBase, sql, arguments, annotations: null)
  {
- Sql = sql;
- Arguments = arguments;
  }
 
+ // See issue#21660/21627
+ ///// <summary>
+ ///// Creates a new instance of the <see cref="FromSqlExpression" /> class.
+ ///// </summary>
+ ///// <param name="sqlQuery">A sql query associated with this table source.</param>
+ //public FromSqlExpression(ISqlQuery sqlQuery)
+ // : this(sqlQuery, sqlQuery.Sql, Constant(Array.Empty<object>(), typeof(object[])))
+ //{
+ //}
+
  private FromSqlExpression(
  string alias,
+ ITableBase tableBase,
  string sql,
  Expression arguments,
  IEnumerable<IAnnotation>? annotations)
  : base(alias, annotations)
  {
+ _table = tableBase;
  Sql = sql;
  Arguments = arguments;
  }
@@ -68,16 +80,19 @@ public override string? Alias
  /// <returns>This expression if no children changed, or an expression with the updated children.</returns>
  public virtual FromSqlExpression Update(Expression arguments)
  => arguments != Arguments
- ? new FromSqlExpression(Alias, Sql, arguments)
+ ? new FromSqlExpression(Alias, _table, Sql, arguments, GetAnnotations())
  : this;
 
+ /// <inheritdoc />
+ ITableBase ITableBasedExpression.Table => _table;
+
  /// <inheritdoc />
  protected override Expression VisitChildren(ExpressionVisitor visitor)
  => this;
 
  /// <inheritdoc />
  public virtual TableExpressionBase Clone()
- => new FromSqlExpression(Alias, Sql, Arguments, GetAnnotations());
+ => new FromSqlExpression(Alias, _table, Sql, Arguments, GetAnnotations());
 
  /// <inheritdoc />
  protected override void Print(ExpressionPrinter expressionPrinter)
@@ -95,6 +110,7 @@ public override bool Equals(object? obj)
 
  private bool Equals(FromSqlExpression fromSqlExpression)
  => base.Equals(fromSqlExpression)
+ && _table == fromSqlExpression._table
  && Sql == fromSqlExpression.Sql
  && ExpressionEqualityComparer.Instance.Equals(Arguments, fromSqlExpression.Arguments);
 

src/EFCore.Relational/Query/SqlExpressions/ITableBasedExpression.cs

@@ -0,0 +1,21 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.EntityFrameworkCore.Query.SqlExpressions;
+
+/// <summary>
+/// <para>
+/// An interface that gives access to <see cref="ITableBase"/> associated with given table source.
+/// </para>
+/// <para>
+/// This type is typically used by database providers (and other extensions). It is generally
+/// not used in application code.
+/// </para>
+/// </summary>
+public interface ITableBasedExpression
+{
+ /// <summary>
+ /// The <see cref="ITableBase"/> associated with given table source.
+ /// </summary>
+ ITableBase Table { get; }
+}

src/EFCore.Relational/Query/SqlExpressions/SelectExpression.cs

@@ -374,13 +374,7 @@ internal SelectExpression(IEntityType entityType, TableExpressionBase tableExpre
  throw new InvalidOperationException(RelationalStrings.SelectExpressionNonTphWithCustomTable(entityType.DisplayName()));
  }
 
- var table = tableExpressionBase switch
- {
- TableExpression tableExpression => tableExpression.Table,
- TableValuedFunctionExpression tableValuedFunctionExpression => tableValuedFunctionExpression.StoreFunction,
- _ => entityType.GetDefaultMappings().Single().Table
- };
-
+ var table = ((ITableBasedExpression)tableExpressionBase).Table;
  var tableReferenceExpression = new TableReferenceExpression(this, tableExpressionBase.Alias!);
  AddTable(tableExpressionBase, tableReferenceExpression);
 

src/EFCore.Relational/Query/SqlExpressions/TableExpression.cs

@@ -13,7 +13,7 @@ namespace Microsoft.EntityFrameworkCore.Query.SqlExpressions;
 /// application or database provider code. If this is a problem for your application or provider, then please file
 /// an issue at <see href="https://github.com/dotnet/efcore">github.com/dotnet/efcore</see>.
 /// </remarks>
-public sealed class TableExpression : TableExpressionBase, IClonableTableExpressionBase
+public sealed class TableExpression : TableExpressionBase, IClonableTableExpressionBase, ITableBasedExpression
 {
  internal TableExpression(ITableBase table)
  : this(table, annotations: null)
@@ -28,6 +28,9 @@ private TableExpression(ITableBase table, IEnumerable<IAnnotation>? annotations)
  Table = table;
  }
 
+ /// <inheritdoc />
+ ITableBase ITableBasedExpression.Table => Table;
+
  /// <inheritdoc />
  protected override void Print(ExpressionPrinter expressionPrinter)
  {

src/EFCore.Relational/Query/SqlExpressions/TableValuedFunctionExpression.cs

@@ -14,7 +14,7 @@ namespace Microsoft.EntityFrameworkCore.Query.SqlExpressions;
 /// not used in application code.
 /// </para>
 /// </summary>
-public class TableValuedFunctionExpression : TableExpressionBase
+public class TableValuedFunctionExpression : TableExpressionBase, ITableBasedExpression
 {
  /// <summary>
  /// Creates a new instance of the <see cref="TableValuedFunctionExpression" /> class.
@@ -61,6 +61,9 @@ public override string? Alias
  /// </summary>
  public virtual IReadOnlyList<SqlExpression> Arguments { get; }
 
+ /// <inheritdoc />
+ ITableBase ITableBasedExpression.Table => StoreFunction;
+
  /// <inheritdoc />
  protected override Expression VisitChildren(ExpressionVisitor visitor)
  {