SqlServer: add support for DateConstruct/TimeConstruct

additionally, improved datetime/date/time construction for versions since v11
by using built-in functions

Author: alex-kulakov

Orm/Xtensive.Orm.SqlServer/Sql.Drivers.SqlServer/v09/Compiler.cs

@@ -219,6 +219,24 @@ public override void Visit(SqlFunctionCall node)
             arguments[1] - 1),
             arguments[2] - 1));
           return;
+#if NET6_0_OR_GREATER
+        case SqlFunctionType.DateConstruct: {
+          Visit(SqlDml.Cast(DateAddDay(DateAddMonth(DateAddYear(SqlDml.Literal(new DateOnly(2001, 1, 1)),
+            arguments[0] - 2001),
+            arguments[1] - 1),
+            arguments[2] - 1), SqlType.Date));
+          return;
+        }
+        case SqlFunctionType.TimeConstruct: {
+          Visit(SqlDml.Cast(DateAddMillisecond(DateAddSecond(DateAddMinute(DateAddHour(SqlDml.Literal(new TimeOnly(0, 0, 0)),
+            arguments[0]),
+            arguments[1]),
+            arguments[2]),
+            arguments[3]), SqlType.Time));
+          return;
+        }
+
+#endif
         case SqlFunctionType.DateTimeToStringIso:
           Visit(DateTimeToStringIso(arguments[0]));
           return;

Orm/Xtensive.Orm.SqlServer/Sql.Drivers.SqlServer/v11/Compiler.cs

@@ -44,6 +44,45 @@ protected override void VisitSelectLimitOffset(SqlSelect node)
       }
     }
 
+    public override void Visit(SqlFunctionCall node)
+    {
+      var arguments = node.Arguments;
+      switch (node.FunctionType) {
+        case SqlFunctionType.DateTimeConstruct:
+          Visit(SqlDml.FunctionCall("DATETIME2FROMPARTS", arguments[0], arguments[1], arguments[2], 0, 0, 0, 0, 7));
+          //Visit(DateAddDay(DateAddMonth(DateAddYear(SqlDml.Literal(new DateTime(2001, 1, 1)),
+          //  arguments[0] - 2001),
+          //  arguments[1] - 1),
+          //  arguments[2] - 1));
+          return;
+#if NET6_0_OR_GREATER
+        case SqlFunctionType.DateConstruct: {
+          Visit(SqlDml.FunctionCall("DATEFROMPARTS", arguments[0], arguments[1], arguments[2]));
+
+          //Visit(SqlDml.Cast(DateAddDay(DateAddMonth(DateAddYear(SqlDml.Literal(new DateOnly(2001, 1, 1)),
+          //  arguments[0] - 2001),
+          //  arguments[1] - 1),
+          //  arguments[2] - 1), SqlType.Date));
+          return;
+        }
+        case SqlFunctionType.TimeConstruct: {
+          // argument[3] * 10000 operation is based on statement that millisaconds use 3 digits
+          // default precision of time is 7, and if we use raw argument[3] value the result will be .0000xxx,
+          // to prevent this and make fractions part valid .xxx0000 we multiply
+          Visit(SqlDml.FunctionCall("TIMEFROMPARTS", arguments[0], arguments[1], arguments[2], arguments[3] * 10000, 7));
+          //Visit(SqlDml.Cast(DateAddMillisecond(DateAddSecond(DateAddMinute(DateAddHour(SqlDml.Literal(new TimeOnly(0, 0, 0)),
+          //  arguments[0]),
+          //  arguments[1]),
+          //  arguments[2]),
+          //  arguments[3]), SqlType.Time));
+          return;
+        }
+#endif
+      }
+
+      base.Visit(node);
+    }
+
     public Compiler(SqlDriver driver)
       : base(driver)
     {