Proposed fix to #7172 - Consider non-default column collation in table variable

src/EFCore.Relational/Extensions/RelationalPropertyExtensions.cs

@@ -1250,9 +1250,7 @@ public static void SetComment(this IMutableProperty property, string? comment)
     /// <param name="property">The property.</param>
     /// <returns>The collation for the column this property is mapped to.</returns>
     public static string? GetCollation(this IReadOnlyProperty property)
-        => (property is RuntimeProperty)
-            ? throw new InvalidOperationException(CoreStrings.RuntimeModelMissingData)
-            : (string?)property.FindAnnotation(RelationalAnnotationNames.Collation)?.Value;
+        => (string?)property.FindAnnotation(RelationalAnnotationNames.Collation)?.Value;
 
     /// <summary>
     ///     Returns the collation to be used for the column.
@@ -1262,11 +1260,6 @@ public static void SetComment(this IMutableProperty property, string? comment)
     /// <returns>The collation for the column this property is mapped to.</returns>
     public static string? GetCollation(this IReadOnlyProperty property, in StoreObjectIdentifier storeObject)
     {
-        if (property is RuntimeProperty)
-        {
-            throw new InvalidOperationException(CoreStrings.RuntimeModelMissingData);
-        }
-
         var annotation = property.FindAnnotation(RelationalAnnotationNames.Collation);
         return annotation != null
             ? (string?)annotation.Value

src/EFCore.SqlServer/Design/Internal/SqlServerCSharpRuntimeAnnotationCodeGenerator.cs

@@ -58,6 +58,11 @@ public override void Generate(IProperty property, CSharpRuntimeAnnotationCodeGen
             {
                 annotations[SqlServerAnnotationNames.ValueGenerationStrategy] = property.GetValueGenerationStrategy();
             }
+
+            if (!annotations.ContainsKey(RelationalAnnotationNames.Collation))
+            {
+                annotations[RelationalAnnotationNames.Collation] = property.GetCollation();
+            }
         }
 
         base.Generate(property, parameters);

src/EFCore.SqlServer/Metadata/Conventions/SqlServerRuntimeModelConvention.cs

@@ -67,6 +67,11 @@ public class SqlServerRuntimeModelConvention : RelationalRuntimeModelConvention
             {
                 annotations[SqlServerAnnotationNames.ValueGenerationStrategy] = property.GetValueGenerationStrategy();
             }
+
+            if (!annotations.ContainsKey(RelationalAnnotationNames.Collation))
+            {
+                annotations[RelationalAnnotationNames.Collation] = property.GetCollation();
+            }
         }
     }
 

src/EFCore.SqlServer/Update/Internal/SqlServerUpdateSqlGenerator.cs

@@ -767,12 +767,15 @@ protected virtual int MergeIntoMinimumThreshold
     private static string GetTypeNameForCopy(IProperty property)
     {
         var typeName = property.GetColumnType();
+        var collation = property[RelationalAnnotationNames.Collation]?.ToString();
 
-        return property.ClrType == typeof(byte[])
+        typeName = property.ClrType == typeof(byte[])
             && (typeName.Equals("rowversion", StringComparison.OrdinalIgnoreCase)
                 || typeName.Equals("timestamp", StringComparison.OrdinalIgnoreCase))
                 ? property.IsNullable ? "varbinary(8)" : "binary(8)"
                 : typeName;
+
+        return collation is null ? typeName : $"{typeName} COLLATE {collation}";
     }
 
     /// <summary>

test/EFCore.Design.Tests/Scaffolding/Internal/CSharpRuntimeModelCodeGeneratorTest.cs

@@ -1904,9 +1904,6 @@ public static void CreateAnnotations(RuntimeEntityType runtimeEntityType)
                         CoreStrings.RuntimeModelMissingData,
                         Assert.Throws<InvalidOperationException>(() => detailsProperty.IsSparse()).Message);
                     Assert.Null(detailsProperty[RelationalAnnotationNames.Collation]);
-                    Assert.Equal(
-                        CoreStrings.RuntimeModelMissingData,
-                        Assert.Throws<InvalidOperationException>(() => detailsProperty.GetCollation()).Message);
 
                     var ownedFragment = referenceOwnedType.GetMappingFragments().Single();
                     Assert.Equal(nameof(OwnedType.Details), detailsProperty.GetColumnName(ownedFragment.StoreObject));