FromTable.cs

Go to the documentation of this file.

// 
//  Copyright 2010-2015 Deveel
// 
//    Licensed under the Apache License, Version 2.0 (the "License");
//    you may not use this file except in compliance with the License.
//    You may obtain a copy of the License at
// 
//        http://www.apache.org/licenses/LICENSE-2.0
// 
//    Unless required by applicable law or agreed to in writing, software
//    distributed under the License is distributed on an "AS IS" BASIS,
//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//    See the License for the specific language governing permissions and
//    limitations under the License.
//

using System;

using Deveel.Data.Serialization;

namespace Deveel.Data.Sql.Expressions {
    [Serializable]
    public sealed class FromTable : IPreparable, ISerializable {
        public FromTable(string tableName, string tableAlias)
            : this(tableName, null, tableAlias) {
            if (String.IsNullOrEmpty(tableName))
                throw new ArgumentNullException("tableName");
        }

        public FromTable(string tableName)
            : this(tableName, null) {
        }

        public FromTable(SqlQueryExpression query) 
            : this(query, null) {
        }

        public FromTable(SqlQueryExpression query, string tableAlias)
            : this(null, query, tableAlias) {
            if (query == null)
                throw new ArgumentNullException("query");
        }

        private FromTable(string tableName, SqlQueryExpression query, string alias) {
            Name = tableName;
            SubQuery = query;
            Alias = alias;
            IsSubQuery = query != null;
        }

        private FromTable(ObjectData data) {
            Name = data.GetString("Name");
            SubQuery = data.GetValue<SqlQueryExpression>("SubQuery");
            Alias = data.GetString("Alias");
            IsSubQuery = data.HasValue("SubQuery");
        }

        public string Name { get; private set; }

        public string Alias { get; private set; }

        internal string UniqueKey { get; set; }

        public bool IsSubQuery { get; private set; }

        public SqlQueryExpression SubQuery { get; private set; }

        object IPreparable.Prepare(IExpressionPreparer preparer) {
            var subQuery = SubQuery;
            if (subQuery != null)
                subQuery = (SqlQueryExpression) subQuery.Prepare(preparer);

            return new FromTable(Name, subQuery, Alias);
        }

        void ISerializable.GetData(SerializeData data) {
            data.SetValue("Name", Name);
            data.SetValue("SubQuery", SubQuery);
            data.SetValue("Alias", Alias);
        }

        //public static void Serialize(FromTable table, BinaryWriter writer) {
        //  if (table.IsSubQuery) {
        //      writer.Write((byte) 2);
        //      SqlExpression.Serialize(table.SubQuery, writer);
        //  } else {
        //      writer.Write((byte)1);
        //      writer.Write(table.Name);
        //  }

        //  bool hasAlias = !String.IsNullOrEmpty(table.Alias);
        //  if (hasAlias) {
        //      writer.Write((byte) 1);
        //      writer.Write(table.Alias);
        //  } else {
        //      writer.Write((byte)0);
        //  }

        //  bool hasUniqueKey = !String.IsNullOrEmpty(table.UniqueKey);
        //  if (hasUniqueKey) {
        //      writer.Write((byte) 1);
        //      writer.Write(table.UniqueKey);
        //  } else {
        //      writer.Write((byte)0);
        //  }
        //}

        //public static FromTable Deserialize(BinaryReader reader) {
        //  string name = null;
        //  SqlQueryExpression query = null;

        //  var type = reader.ReadByte();
        //  if (type == 1) {
        //      name = reader.ReadString();
        //  } else if (type == 2) {
        //      query = (SqlQueryExpression) SqlExpression.Deserialize(reader);
        //  } else {
        //      throw new FormatException();
        //  }

        //  string alias = null;
        //  var hasAlias = reader.ReadByte() == 1;
        //  if (hasAlias)
        //      alias = reader.ReadString();

        //  FromTable table;
        //  if (type == 1) {
        //      table = new FromTable(name, alias);
        //  } else {
        //      table = new FromTable(query, alias);
        //  }

        //  var hasUniqueKey = reader.ReadByte() == 1;
        //  if (hasUniqueKey)
        //      table.UniqueKey = reader.ReadString();

        //  return table;
        //}
    }
}