linq2db · MaceWindu · Jun 29, 2024 · Jun 17, 2024 · Jun 17, 2024 · Jun 18, 2024
@@ -45,12 +45,13 @@ protected ClickHouseDataProvider(string name, ClickHouseProvider provider)
 			// as emulation doesn't work properly due to missing rowcount functionality
 			SqlProviderFlags.IsInsertOrUpdateSupported         = true;
 
-			SqlProviderFlags.IsUpdateFromSupported             = false;
-			SqlProviderFlags.IsCommonTableExpressionsSupported = true;
-			SqlProviderFlags.IsSubQueryOrderBySupported        = true;
-			SqlProviderFlags.DoesNotSupportCorrelatedSubquery  = true;
-			SqlProviderFlags.IsAllSetOperationsSupported       = true;
-			SqlProviderFlags.IsNestedJoinsSupported            = false;
+			SqlProviderFlags.IsUpdateFromSupported                 = false;
+			SqlProviderFlags.IsCommonTableExpressionsSupported     = true;
+			SqlProviderFlags.IsSubQueryOrderBySupported            = true;
+			SqlProviderFlags.DoesNotSupportCorrelatedSubquery      = true;
+			SqlProviderFlags.IsAllSetOperationsSupported           = true;
+			SqlProviderFlags.IsNestedJoinsSupported                = false;
+			SqlProviderFlags.IsSupportedSimpleCorrelatedSubqueries = true;
 
 			// unconfigured flags
 			// 1. ClickHouse doesn't support correlated subqueries at all so this flag's value doesn't make difference

@@ -139,16 +139,18 @@ protected override ISqlExpression ConvertConversion(SqlCastExpression cast)
 			return base.ConvertConversion(cast);
 		}
 
-		protected override ISqlExpression WrapBooleanExpression(ISqlExpression expr)
+		protected override ISqlExpression WrapColumnExpression(ISqlExpression expr)
 		{
-			var newExpr = base.WrapBooleanExpression(expr);
-			if (!ReferenceEquals(newExpr, expr))
+			var columnExpression = base.WrapColumnExpression(expr);
+
+			if (SqlProviderFlags != null 
+			    && columnExpression.SystemType == typeof(bool)
+			    && QueryHelper.UnwrapNullablity(columnExpression) is not (SqlCastExpression or SqlColumn or SqlField))
 			{
-				return new SqlCastExpression(newExpr, new DbDataType(expr.SystemType ?? typeof(bool), DataType.Boolean), null, isMandatory : true);
+				columnExpression = new SqlCastExpression(columnExpression, new DbDataType(columnExpression.SystemType!, DataType.Boolean), null, isMandatory: true);
 			}
 
-			return newExpr;
+			return columnExpression;
 		}
-
 	}
 }
@@ -113,7 +113,7 @@ protected override BuildSequenceResult BuildMethodCall(ExpressionBuilder builder
 
 				if (!buildInfo.IsSubQuery)
 				{
-					if (!SequenceHelper.IsSupportedSubquery(resultSelectContext, resultSelectContext, out var errorMessage))
+					if (!builder.IsSupportedSubquery(resultSelectContext, resultSelectContext, out var errorMessage))
 						return BuildSequenceResult.Error(methodCall, errorMessage);
 				}
 

@@ -227,7 +227,7 @@ public Expression TryCreateAssociation(Expression expression, ContextRefExpressi
 
 				if (!flags.IsTest())
 				{
-					if (!SequenceHelper.IsSupportedSubquery(rootContext.BuildContext, sequence, out var errorMessage))
+					if (!IsSupportedSubquery(rootContext.BuildContext, sequence, out var errorMessage))
 						return new SqlErrorExpression(null, expression, errorMessage, expression.Type, true);
 				}
 

@@ -386,6 +386,11 @@ Expression ProcessEagerLoadingExpression(
 				_associations    = saveAssociationsCache;
 			}
 
+			if (resultExpression is SqlErrorExpression errorExpression)
+			{
+				return errorExpression.WithType(eagerLoad.Type);
+			}
+
 			resultExpression = SqlAdjustTypeExpression.AdjustType(resultExpression, eagerLoad.Type, MappingSchema);
 
 			return resultExpression;
@@ -433,7 +438,8 @@ Expression BuildPreambleQueryAttached<TKey, T>(
 
 			query.Init(sequence, _parametersContext.CurrentSqlParameters);
 
-			BuildQuery(query, sequence, queryParameter, ref preambles!, previousKeys);
+			if (!BuildQuery(query, sequence, queryParameter, ref preambles!, previousKeys))
+				return query.ErrorExpression!;
 
 			var idx      = preambles.Count;
 			var preamble = new Preamble<TKey, T>(query);
@@ -493,6 +499,10 @@ Expression CompleteEagerLoadingExpressions(
 			{
 				if (e.NodeType == ExpressionType.Extension && e is SqlEagerLoadExpression eagerLoad)
 				{
+					// Do not process eager loading fast mode
+					if (!_validateSubqueries)
+						return SqlErrorExpression.EnsureError(eagerLoad.SequenceExpression, e.Type);
+
 					eagerLoadingCache ??= new Dictionary<Expression, Expression>(ExpressionEqualityComparer.Instance);
 					if (!eagerLoadingCache.TryGetValue(eagerLoad.SequenceExpression, out var preambleExpression))
 					{

@@ -860,51 +860,52 @@ public override Expression VisitPlaceholderExpression(PlaceholderExpression node
 
 			protected override Expression VisitConditional(ConditionalExpression node)
 			{
-				if (_flags.IsSql())
+				var saveFlags = _flags;
+
+				_flags |= ProjectFlags.ForceOuterAssociation;
+				try
 				{
-					var translated = TranslateExpression(node);
+					var translated = TranslateExpression(node, useSql: true);
 
 					if (translated is SqlPlaceholderExpression)
 						return translated;
-				}
 
-				if (IsForcedToConvert(node))
-				{
-					return TranslateExpression(node);
-				}
+					if (IsForcedToConvert(node))
+					{
+						return TranslateExpression(node);
+					}
 
-				var saveFlags      = _flags;
+					var saveDescriptor = _columnDescriptor;
+					_columnDescriptor = null;
+					var test           = Visit(node.Test);
+					_columnDescriptor = saveDescriptor;
 
-				_flags |= ProjectFlags.ForceOuterAssociation;
+					var ifTrue  = Visit(node.IfTrue);
+					var ifFalse = Visit(node.IfFalse);
 
-				var saveDescriptor = _columnDescriptor;
-				_columnDescriptor = null;
-				var test           = Visit(node.Test);
-				_columnDescriptor  = saveDescriptor;
+					if (test is ConstantExpression { Value: bool boolValue })
+					{
+						return boolValue ? ifTrue : ifFalse;
+					}
 
-				var ifTrue  = Visit(node.IfTrue);
-				var ifFalse = Visit(node.IfFalse);
+					if (ifTrue is SqlGenericConstructorExpression && ifFalse is SqlPlaceholderExpression)
+						ifFalse = node.IfFalse;
+					else if (ifFalse is SqlGenericConstructorExpression && ifTrue is SqlPlaceholderExpression)
+						ifTrue = node.IfTrue;
 
-				_flags = saveFlags;
+					if (test is SqlPlaceholderExpression   &&
+					    ifTrue is SqlPlaceholderExpression &&
+					    ifFalse is SqlPlaceholderExpression)
+					{
+						return TranslateExpression(node, useSql: true);
+					}
 
-				if (test is ConstantExpression { Value: bool boolValue })
-				{
-					return boolValue ? ifTrue : ifFalse;
+					return node.Update(test, ifTrue, ifFalse);
 				}
-
-				if (ifTrue is SqlGenericConstructorExpression && ifFalse is SqlPlaceholderExpression)
-					ifFalse = node.IfFalse;
-				else if (ifFalse is SqlGenericConstructorExpression && ifTrue is SqlPlaceholderExpression)
-					ifTrue = node.IfTrue;
-
-				if (test is SqlPlaceholderExpression   &&
-				    ifTrue is SqlPlaceholderExpression &&
-					ifFalse is SqlPlaceholderExpression)
+				finally
 				{
-					return TranslateExpression(node, useSql : true);
+					_flags = saveFlags;
 				}
-
-				return node.Update(test, ifTrue, ifFalse);
 			}
 
 			public override Expression VisitSqlDefaultIfEmptyExpression(SqlDefaultIfEmptyExpression node)

@@ -162,14 +162,16 @@ Expression FinalizeProjection<T>(
 
 			// process eager loading queries
 			var correctedEager = CompleteEagerLoadingExpressions(postProcessed, context, queryParameter, ref preambles, previousKeys);
+
+			if (SequenceHelper.HasError(correctedEager))
+				return correctedEager;
+
 			if (!ExpressionEqualityComparer.Instance.Equals(correctedEager, postProcessed))
 			{
 				// convert all missed references
 				postProcessed = FinalizeConstructors(context, correctedEager, false);
 			}
 
-			SequenceHelper.EnsureNoErrors(postProcessed);
-
 			var withColumns = ToColumns(context, postProcessed);
 			return withColumns;
 		}

@@ -17,11 +17,12 @@ namespace LinqToDB.Linq.Builder
 	using Common.Internal;
 	using Data;
 	using Extensions;
-	using Linq.Translation;
+	using Translation;
 	using LinqToDB.Expressions;
 	using Mapping;
 	using Reflection;
 	using SqlQuery;
+	using DataProvider;
 
 	partial class ExpressionBuilder
 	{
@@ -150,6 +151,79 @@ public void BuildSkip(IBuildContext sequence, ISqlExpression expr)
 
 		#region SubQueryToSql
 
+		/// <summary>
+		/// Checks that provider can handle limitation inside subquery. This function is tightly coupled with <see cref="SelectQueryOptimizerVisitor.OptimizeApply"/>
+		/// </summary>
+		/// <param name="context"></param>
+		/// <returns></returns>
+		public bool IsSupportedSubquery(IBuildContext parent, IBuildContext context, out string? errorMessage)
+		{
+			errorMessage = null;
+
+			if (!_validateSubqueries)
+				return true;
+
+			// No check during recursion. Cloning may fail
+			if (parent.Builder.IsRecursiveBuild)
+				return true;
+
+			if (!context.Builder.DataContext.SqlProviderFlags.IsApplyJoinSupported)
+			{
+				// We are trying to simulate what will be with query after optimizer's work
+				//
+				var cloningContext = new CloningContext();
+
+				var clonedParentContext = cloningContext.CloneContext(parent);
+				var clonedContext       = cloningContext.CloneContext(context);
+
+				cloningContext.UpdateContextParents();
+
+				var expr = parent.Builder.MakeExpression(clonedContext, new ContextRefExpression(clonedContext.ElementType, clonedContext), ProjectFlags.SQL);
+
+				expr = parent.Builder.ToColumns(clonedParentContext, expr);
+
+				SqlJoinedTable? fakeJoin = null;
+
+				// add fake join there is no still reference
+				if (null == clonedParentContext.SelectQuery.Find(e => e is SelectQuery sc && sc == clonedContext.SelectQuery))
+				{
+					fakeJoin = clonedContext.SelectQuery.OuterApply().JoinedTable;
+
+					clonedParentContext.SelectQuery.From.Tables[0].Joins.Add(fakeJoin);
+				}
+
+				using var visitor = QueryHelper.SelectOptimizer.Allocate();
+
+#if DEBUG
+
+				var sqlText = clonedParentContext.SelectQuery.ToDebugString();
+
+#endif
+
+				var optimizedQuery = (SelectQuery)visitor.Value.Optimize(
+					root: clonedParentContext.SelectQuery,
+					rootElement: clonedParentContext.SelectQuery,
+					providerFlags: parent.Builder.DataContext.SqlProviderFlags,
+					removeWeakJoins: false,
+					dataOptions: parent.Builder.DataOptions,
+					mappingSchema: context.MappingSchema,
+					evaluationContext: new EvaluationContext()
+				);
+
+				if (!SqlProviderHelper.IsValidQuery(optimizedQuery, 
+					    parentQuery: null, 
+					    fakeJoin: fakeJoin, 
+					    forColumn: false, 
+					    parent.Builder.DataContext.SqlProviderFlags, 
+					    out errorMessage))
+				{
+					return false;
+				}
+			}
+
+			return true;
+		}
+
 		int _gettingSubquery;
 
 		public IBuildContext? GetSubQuery(IBuildContext context, Expression expr, ProjectFlags flags, out bool isSequence, out string? errorMessage)
@@ -174,7 +248,10 @@ public void BuildSkip(IBuildContext sequence, ISqlExpression expr)
 			{
 				if (_gettingSubquery == 0)
 				{
-					if (!SequenceHelper.IsSupportedSubquery(context, buildResult.BuildContext, out errorMessage))
+					++_gettingSubquery;
+					var isSupported = IsSupportedSubquery(context, buildResult.BuildContext, out errorMessage);
+					--_gettingSubquery;
+					if (!isSupported)
 						return null;
 				}
 			}
@@ -856,6 +933,9 @@ Expression ConvertToSqlInternal(IBuildContext? context, Expression expression, P
 						if (e.Method == null && (e.IsLifted || e.Type == typeof(object)))
 							return placeholder;
 
+						if (e.Method == null && operandExpr is not SqlPlaceholderExpression)
+							return e;
+
 						if (e.Type == typeof(bool) && e.Operand.Type == typeof(SqlBoolean))
 							return placeholder;
 
@@ -890,9 +970,9 @@ Expression ConvertToSqlInternal(IBuildContext? context, Expression expression, P
 				{
 					var e = (ConditionalExpression)expression;
 
-					var testExpr  = ConvertToSqlExpr(context, e.Test,    flags.TestFlag(), columnDescriptor : columnDescriptor, isPureExpression : isPureExpression);
-					var trueExpr  = ConvertToSqlExpr(context, e.IfTrue,  flags.TestFlag(), columnDescriptor : columnDescriptor, isPureExpression : isPureExpression);
-					var falseExpr = ConvertToSqlExpr(context, e.IfFalse, flags.TestFlag(), columnDescriptor : columnDescriptor, isPureExpression : isPureExpression);
+					var testExpr  = ConvertToSqlExpr(context, e.Test,    flags.TestFlag(), columnDescriptor: null, isPureExpression: isPureExpression);
+					var trueExpr  = ConvertToSqlExpr(context, e.IfTrue,  flags.TestFlag(), columnDescriptor: columnDescriptor, isPureExpression: isPureExpression);
+					var falseExpr = ConvertToSqlExpr(context, e.IfFalse, flags.TestFlag(), columnDescriptor: columnDescriptor, isPureExpression: isPureExpression);
 
 					if (testExpr is SqlPlaceholderExpression &&
 						trueExpr is SqlPlaceholderExpression &&
@@ -2090,6 +2170,8 @@ Expression GenerateConstructorComparison(SqlGenericConstructorExpression leftCon
 
 					if (l is SqlValue lv && lv.Value == null || left.IsNullValue())
 					{
+						rightExpr = BuildSqlExpression(context, rightExpr, flags);
+
 						if (rightExpr is ConditionalExpression { Test: SqlPlaceholderExpression { Sql: SqlSearchCondition rightSearchCond } } && rightSearchCond.Predicates.Count == 1)
 						{
 							var rightPredicate  = rightSearchCond.Predicates[0];
@@ -2104,13 +2186,13 @@ Expression GenerateConstructorComparison(SqlGenericConstructorExpression leftCon
 							}
 						}
 
-						rightExpr = BuildSqlExpression(context, rightExpr, flags);
-
 						return GenerateNullComparison(rightExpr, isNot);
 					}
 
 					if (r is SqlValue rv && rv.Value == null || right.IsNullValue())
 					{
+						leftExpr = BuildSqlExpression(context, leftExpr, flags);
+
 						if (leftExpr is ConditionalExpression { Test: SqlPlaceholderExpression { Sql: SqlSearchCondition leftSearchCond } } && leftSearchCond.Predicates.Count == 1)
 						{
 							var leftPredicate  = leftSearchCond.Predicates[0];
@@ -2125,8 +2207,6 @@ Expression GenerateConstructorComparison(SqlGenericConstructorExpression leftCon
 							}
 						}
 
-						leftExpr = BuildSqlExpression(context, leftExpr, flags);
-
 						return GenerateNullComparison(leftExpr, isNot);
 					}
 
@@ -2380,18 +2460,6 @@ public bool CollectNullCompareExpressions(IBuildContext context, Expression expr
 		{
 			switch (expression.NodeType)
 			{
-				case ExpressionType.Conditional:
-				{
-					var cond = (ConditionalExpression)expression;
-
-					if (!CollectNullCompareExpressions(context, cond.IfTrue, result))
-						return false;
-					if (!CollectNullCompareExpressions(context, cond.IfFalse, result))
-						return false;
-
-					return true;
-				}
-
 				case ExpressionType.Constant:
 				case ExpressionType.Default:
 				{
@@ -4266,7 +4334,7 @@ public Expression Project(IBuildContext context, Expression? path, List<Expressi
 						return new DefaultValueExpression(MappingSchema, truePath.Type);
 					}
 
-					var falsePath = new DefaultValueExpression(MappingSchema, truePath.Type);
+					var falsePath = Expression.Constant(null, truePath.Type);
 
 					var conditional = Expression.Condition(isPredicate, truePath, falsePath);