Fix RowCountAsync impls

Author: mythz

src/ServiceStack.OrmLite/Async/ReadExpressionCommandExtensionsAsync.cs

@@ -161,13 +161,16 @@ internal static Task<long> GetCountAsync(this IDbCommand dbCmd, string sql, IEnu
 
         internal static Task<long> RowCountAsync<T>(this IDbCommand dbCmd, SqlExpression<T> expression, CancellationToken token)
         {
-            var sql = $"SELECT COUNT(*) FROM ({expression.ToSelectStatement()}) AS COUNT";
-            return dbCmd.ScalarAsync<long>(sql, token);
+            var countExpr = expression.Clone().OrderBy();
+            return dbCmd.ScalarAsync<long>(dbCmd.GetDialectProvider().ToRowCountStatement(countExpr.ToSelectStatement()), expression.Params, token);
         }
 
-        internal static Task<long> RowCountAsync(this IDbCommand dbCmd, string sql, CancellationToken token)
+        internal static Task<long> RowCountAsync(this IDbCommand dbCmd, string sql, object anonType, CancellationToken token)
         {
-            return dbCmd.ScalarAsync<long>($"SELECT COUNT(*) FROM ({sql}) AS COUNT", token);
+            if (anonType != null)
+                dbCmd.SetParameters(anonType.ToObjectDictionary(), excludeDefaults: false, sql:ref sql);
+
+            return dbCmd.ScalarAsync<long>(dbCmd.GetDialectProvider().ToRowCountStatement(sql), token);
         }
 
         internal static Task<List<T>> LoadSelectAsync<T>(this IDbCommand dbCmd, SqlExpression<T> expression = null, string[] include = null, CancellationToken token = default(CancellationToken))

src/ServiceStack.OrmLite/OrmLiteReadExpressionsApiAsync.cs

@@ -151,9 +151,9 @@ public static Task<TKey> ScalarAsync<T, TKey>(this IDbConnection dbConn,
         /// <summary>
         /// Return the number of rows returned by the supplied sql
         /// </summary>
-        public static Task<long> RowCountAsync(this IDbConnection dbConn, string sql, CancellationToken token = default(CancellationToken))
+        public static Task<long> RowCountAsync(this IDbConnection dbConn, string sql, object anonType = null, CancellationToken token = default(CancellationToken))
         {
-            return dbConn.Exec(dbCmd => dbCmd.RowCountAsync(sql, token));
+            return dbConn.Exec(dbCmd => dbCmd.RowCountAsync(sql, anonType, token));
         }
 
         /// <summary>

tests/ServiceStack.OrmLite.Tests/Issues/LRAIssues.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Data;
 using System.Linq;
+using System.Threading.Tasks;
 using NUnit.Framework;
 using ServiceStack.DataAnnotations;
 using ServiceStack.Model;
@@ -113,6 +114,20 @@ public void Does_select_aliases_on_custom_expressions()
                 Assert.That(lastStatement, Does.Contain("as statowarning"));
             }
         }
+
+        [Test]
+        public async Task Does_RowCount_LRARichiesta_Async()
+        {
+            using (var db = OpenDbConnection())
+            {
+                db.DropAndCreateTable<LRARichiesta>();
+                
+                var q = db.From<LRARichiesta>()
+                    .Where(x => x.Id > 0);
+
+                var result = await db.RowCountAsync(q);                
+            }
+        }
 
         private static void CreateTables(IDbConnection db)
         {