SqlServer: date constant in DateAdd method is always datetime

src/EFCore.SqlServer/Query/Internal/SqlServerDateTimeMethodTranslator.cs

@@ -8,6 +8,7 @@
 using Microsoft.EntityFrameworkCore.Diagnostics;
 using Microsoft.EntityFrameworkCore.Query;
 using Microsoft.EntityFrameworkCore.Query.SqlExpressions;
+using Microsoft.EntityFrameworkCore.Storage;
 using Microsoft.EntityFrameworkCore.Utilities;
 
 #nullable enable
@@ -41,16 +42,20 @@ public class SqlServerDateTimeMethodTranslator : IMethodCallTranslator
         };
 
         private readonly ISqlExpressionFactory _sqlExpressionFactory;
+        private readonly IRelationalTypeMappingSource _typeMappingSource;
 
         /// <summary>
         ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
         ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
         ///     any release. You should only use it directly in your code with extreme caution and knowing that
         ///     doing so can result in application failures when updating to a new Entity Framework Core release.
         /// </summary>
-        public SqlServerDateTimeMethodTranslator([NotNull] ISqlExpressionFactory sqlExpressionFactory)
+        public SqlServerDateTimeMethodTranslator(
+            [NotNull] ISqlExpressionFactory sqlExpressionFactory,
+            [NotNull] IRelationalTypeMappingSource typeMappingSource)
         {
             _sqlExpressionFactory = sqlExpressionFactory;
+            _typeMappingSource = typeMappingSource;
         }
 
         /// <summary>
@@ -74,24 +79,32 @@ public SqlServerDateTimeMethodTranslator([NotNull] ISqlExpressionFactory sqlExpr
             {
                 // DateAdd does not accept number argument outside of int range
                 // AddYears/AddMonths take int argument so no need to check for range
-                return datePart != "year"
+                if (datePart != "year"
                     && datePart != "month"
                     && arguments[0] is SqlConstantExpression sqlConstant
                     && ((double)sqlConstant.Value >= int.MaxValue
-                        || (double)sqlConstant.Value <= int.MinValue)
-                        ? null
-                        : _sqlExpressionFactory.Function(
-                            "DATEADD",
-                            new[]
-                            {
-                                _sqlExpressionFactory.Fragment(datePart),
-                                _sqlExpressionFactory.Convert(arguments[0], typeof(int)),
-                                instance
-                            },
-                            nullable: true,
-                            argumentsPropagateNullability: new[] { false, true, true },
-                            instance.Type,
-                            instance.TypeMapping);
+                        || (double)sqlConstant.Value <= int.MinValue))
+                {
+                    return null;
+                }
+
+                if (instance is SqlConstantExpression instanceConstant)
+                {
+                    instance = instanceConstant.ApplyTypeMapping(_typeMappingSource.FindMapping(typeof(DateTime), "datetime"));
+                }
+
+                return _sqlExpressionFactory.Function(
+                    "DATEADD",
+                    new[]
+                    {
+                        _sqlExpressionFactory.Fragment(datePart),
+                        _sqlExpressionFactory.Convert(arguments[0], typeof(int)),
+                        instance
+                    },
+                    nullable: true,
+                    argumentsPropagateNullability: new[] { false, true, true },
+                    instance.Type,
+                    instance.TypeMapping);
             }
 
             return null;

src/EFCore.SqlServer/Query/Internal/SqlServerMethodCallTranslatorProvider.cs

@@ -34,7 +34,7 @@ public SqlServerMethodCallTranslatorProvider([NotNull] RelationalMethodCallTrans
                     new SqlServerConvertTranslator(sqlExpressionFactory),
                     new SqlServerDataLengthFunctionTranslator(sqlExpressionFactory),
                     new SqlServerDateDiffFunctionsTranslator(sqlExpressionFactory),
-                    new SqlServerDateTimeMethodTranslator(sqlExpressionFactory),
+                    new SqlServerDateTimeMethodTranslator(sqlExpressionFactory, typeMappingSource),
                     new SqlServerFromPartsFunctionTranslator(sqlExpressionFactory, typeMappingSource),
                     new SqlServerFullTextSearchFunctionsTranslator(sqlExpressionFactory),
                     new SqlServerIsDateFunctionTranslator(sqlExpressionFactory),

test/EFCore.Cosmos.FunctionalTests/Query/NorthwindMiscellaneousQueryCosmosTest.cs

@@ -2580,6 +2580,17 @@ FROM root c
 WHERE ((c[""Discriminator""] = ""Order"") AND (c[""OrderDate""] != null))");
         }
 
+        public override async Task Add_minutes_on_constant_value(bool async)
+        {
+            await base.Add_minutes_on_constant_value(async);
+
+            AssertSql(
+                @"SELECT VALUE {""c"" : (c[""OrderID""] % 25)}
+FROM root c
+WHERE ((c[""Discriminator""] = ""Order"") AND (c[""OrderID""] < 10500))
+ORDER BY c[""OrderID""]");
+        }
+
         [ConditionalTheory(Skip = "Issue #17246")]
         public override async Task Select_expression_references_are_updated_correctly_with_subquery(bool async)
         {

test/EFCore.Specification.Tests/Query/NorthwindMiscellaneousQueryTestBase.cs

@@ -4194,6 +4194,19 @@ public virtual Task Select_expression_date_add_milliseconds_large_number_divided
                 e => e.OrderDate);
         }
 
+        [ConditionalTheory]
+        [MemberData(nameof(IsAsyncData))]
+        public virtual Task Add_minutes_on_constant_value(bool async)
+        {
+            return AssertQuery(
+                async,
+                ss => ss.Set<Order>().Where(c => c.OrderID < 10500)
+                    .OrderBy(o => o.OrderID)
+                    .Select(o => new { Test = new DateTime(1900, 1, 1).AddMinutes(o.OrderID % 25) }),
+                assertOrder: true,
+                elementAsserter: (e, a) => AssertEqual(e.Test, a.Test));
+        }
+
         [ConditionalTheory]
         [MemberData(nameof(IsAsyncData))]
         public virtual Task Select_expression_references_are_updated_correctly_with_subquery(bool async)

test/EFCore.SqlServer.FunctionalTests/Query/NorthwindMiscellaneousQuerySqlServerTest.cs

@@ -3229,6 +3229,17 @@ FROM [Orders] AS [o]
 WHERE [o].[OrderDate] IS NOT NULL");
         }
 
+        public override async Task Add_minutes_on_constant_value(bool async)
+        {
+            await base.Add_minutes_on_constant_value(async);
+
+            AssertSql(
+                @"SELECT DATEADD(minute, CAST(CAST(([o].[OrderID] % 25) AS float) AS int), '1900-01-01T00:00:00.000') AS [Test]
+FROM [Orders] AS [o]
+WHERE [o].[OrderID] < 10500
+ORDER BY [o].[OrderID]");
+        }
+
         public override async Task Select_expression_references_are_updated_correctly_with_subquery(bool async)
         {
             await base.Select_expression_references_are_updated_correctly_with_subquery(async);

test/EFCore.Sqlite.FunctionalTests/Query/NorthwindMiscellaneousQuerySqliteTest.cs

@@ -172,6 +172,17 @@ SELECT rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', ""o"".""OrderDate"", COALESCE(C
 WHERE ""o"".""OrderDate"" IS NOT NULL");
         }
 
+        public override async Task Add_minutes_on_constant_value(bool async)
+        {
+            await base.Add_minutes_on_constant_value(async);
+
+            AssertSql(
+                @"SELECT rtrim(rtrim(strftime('%Y-%m-%d %H:%M:%f', '1900-01-01 00:00:00', CAST(CAST((""o"".""OrderID"" % 25) AS REAL) AS TEXT) || ' minutes'), '0'), '.') AS ""Test""
+FROM ""Orders"" AS ""o""
+WHERE ""o"".""OrderID"" < 10500
+ORDER BY ""o"".""OrderID""");
+        }
+
         public override async Task Select_distinct_long_count(bool async)
         {
             await base.Select_distinct_long_count(async);