DynamORM/DynamicDatabase.cs

@@ -860,6 +860,31 @@ namespace DynamORM
 
         #region Schema
 
+        /// <summary>Builds query cache if necessary and returns it.</summary>
+        /// <param name="builder">The builder containing query to read schema from.</param>
+        /// <returns>Query schema.</returns>
+        public Dictionary<string, DynamicSchemaColumn> GetQuerySchema(IDynamicSelectQueryBuilder builder)
+        {
+            using (var con = Open())
+            using (var cmd = con.CreateCommand().SetCommand(builder))
+                return ReadSchema(cmd)
+                    .Distinct()
+                    .ToDictionary(k => k.Name.ToLower(), k => k);
+        }
+
+        /// <summary>Builds query cache if necessary and returns it.</summary>
+        /// <param name="sql">Sql query from which read schema.</param>
+        /// <param name="args">Sql query argumants.</param>
+        /// <returns>Query schema.</returns>
+        public Dictionary<string, DynamicSchemaColumn> GetQuerySchema(string sql, params object[] args)
+        {
+            using (var con = Open())
+            using (var cmd = con.CreateCommand().SetCommand(sql, args))
+                return ReadSchema(cmd)
+                    .Distinct()
+                    .ToDictionary(k => k.Name.ToLower(), k => k);
+        }
+
         /// <summary>Builds table cache if necessary and returns it.</summary>
         /// <param name="table">Name of table for which build schema.</param>
         /// <param name="owner">Owner of table for which build schema.</param>
@@ -917,29 +942,35 @@ namespace DynamORM
         protected virtual IEnumerable<DynamicSchemaColumn> ReadSchema(string table, string owner)
         {
             using (var con = Open())
-            using (var cmd = con.CreateCommand())
-            {
-                using (var rdr = cmd
-                    .SetCommand(string.Format("SELECT * FROM {0}{1} WHERE 1 = 0",
-                        !string.IsNullOrEmpty(owner) ? string.Format("{0}.", DecorateName(owner)) : string.Empty,
-                        DecorateName(table)))
-                    .ExecuteReader(CommandBehavior.SchemaOnly | CommandBehavior.KeyInfo))
-                    foreach (DataRow col in rdr.GetSchemaTable().Rows)
-                    {
-                        var c = col.RowToDynamicUpper();
+            using (var cmd = con.CreateCommand()
+                .SetCommand(string.Format("SELECT * FROM {0}{1} WHERE 1 = 0",
+                    !string.IsNullOrEmpty(owner) ? string.Format("{0}.", DecorateName(owner)) : string.Empty,
+                    DecorateName(table))))
+                return ReadSchema(cmd);
+        }
 
-                        yield return new DynamicSchemaColumn
-                        {
-                            Name = c.COLUMNNAME,
-                            Type = DynamicExtensions.TypeMap.TryGetNullable((Type)c.DATATYPE) ?? DbType.String,
-                            IsKey = c.ISKEY ?? false,
-                            IsUnique = c.ISUNIQUE ?? false,
-                            Size = (int)(c.COLUMNSIZE ?? 0),
-                            Precision = (byte)(c.NUMERICPRECISION ?? 0),
-                            Scale = (byte)(c.NUMERICSCALE ?? 0)
-                        };
-                    }
-            }
+        /// <summary>Get schema describing objects from reader.</summary>
+        /// <param name="cmd">Command containing query to execute.</param>
+        /// <returns>List of <see cref="DynamicSchemaColumn"/> objects .
+        /// If your database doesn't get those values in upper case (like most of the databases) you should override this method.</returns>
+        protected virtual IEnumerable<DynamicSchemaColumn> ReadSchema(IDbCommand cmd)
+        {
+            using (var rdr = cmd.ExecuteReader(CommandBehavior.SchemaOnly | CommandBehavior.KeyInfo))
+                foreach (DataRow col in rdr.GetSchemaTable().Rows)
+                {
+                    var c = col.RowToDynamicUpper();
+
+                    yield return new DynamicSchemaColumn
+                    {
+                        Name = c.COLUMNNAME,
+                        Type = DynamicExtensions.TypeMap.TryGetNullable((Type)c.DATATYPE) ?? DbType.String,
+                        IsKey = c.ISKEY ?? false,
+                        IsUnique = c.ISUNIQUE ?? false,
+                        Size = (int)(c.COLUMNSIZE ?? 0),
+                        Precision = (byte)(c.NUMERICPRECISION ?? 0),
+                        Scale = (byte)(c.NUMERICSCALE ?? 0)
+                    };
+                }
         }
 
         private Dictionary<string, DynamicSchemaColumn> BuildAndCacheSchema(string tableName, DynamicTypeMap mapper, string owner = null)
@@ -959,6 +990,7 @@ namespace DynamORM
             if (databaseSchemaSupport && !Schema.ContainsKey(tableName.ToLower()))
             {
                 schema = ReadSchema(tableName, owner)
+                    .Distinct()
                     .ToDictionary(k => k.Name.ToLower(), k => k);
 
                 Schema[tableName.ToLower()] = schema;
@@ -1237,7 +1269,47 @@ namespace DynamORM
         {
             _tempConn = Open() as DynamicConnection;
 
-            return _tempConn.BeginTransaction(null, () =>
+            return _tempConn.BeginTransaction(null, null, () =>
+            {
+                var t = TransactionPool.TryGetValue(_tempConn.Connection);
+
+                if (t == null | t.Count == 0)
+                {
+                    _tempConn.Dispose();
+                    _tempConn = null;
+                }
+            });
+        }
+
+        /// <summary>Begins a database transaction with the specified
+        /// <see cref="System.Data.IsolationLevel"/> value.</summary>
+        /// <param name="il">One of the <see cref="System.Data.IsolationLevel"/> values.</param>
+        /// <returns>Returns <see cref="DynamicTransaction"/> representation.</returns>
+        public IDbTransaction BeginTransaction(IsolationLevel il)
+        {
+            _tempConn = Open() as DynamicConnection;
+
+            return _tempConn.BeginTransaction(il, null, () =>
+            {
+                var t = TransactionPool.TryGetValue(_tempConn.Connection);
+
+                if (t == null | t.Count == 0)
+                {
+                    _tempConn.Dispose();
+                    _tempConn = null;
+                }
+            });
+        }
+
+        /// <summary>Begins a database transaction with the specified
+        /// <see cref="System.Data.IsolationLevel"/> value.</summary>
+        /// <param name="custom">Custom parameter describing transaction options.</param>
+        /// <returns>Returns <see cref="DynamicTransaction"/> representation.</returns>
+        public IDbTransaction BeginTransaction(object custom)
+        {
+            _tempConn = Open() as DynamicConnection;
+
+            return _tempConn.BeginTransaction(null, custom, () =>
             {
                 var t = TransactionPool.TryGetValue(_tempConn.Connection);