DataTable.cs

using System;
using System.Collections.ObjectModel;
using System.Collections.Generic;
using System.Linq;

namespace UnityORM
{
    public class DataRow : Dictionary<string, object>
    {
        public new object this [string column] {
            get {
                if (ContainsKey (column))
                {
                    return base [column];
                }

                return null;
            }
            set {
                if (ContainsKey (column))
                {
                    base [column] = value;
                }
                else
                {
                    Add (column, value);
                }
            }
        }

        public DateTime GetAsDateTime (string column)
        {
            return DateTime.FromBinary (GetAsLong (column));
        }

        public string GetAsString (string column)
        {
            object v = this [column];
            if (v == null)
            {
                return null;
            }
            else
            {
                return v.ToString ();
            }
        }

        public long GetAsLong (string column)
        {
            object v = this [column];
            if (v == null)
            {
                return 0;
            }
            else if (v is long)
            {
                return (long)v;
            }
            else if (v is int)
            {
                return (long)(int)v;
            }
            else if (v is double)
            {
                return (long)(double)v;
            }
            else if (v is string)
            {
                return long.Parse ((string)v);
            }
            else
            {
                return int.Parse (v.ToString ());
            }
        }

        public int GetAsInt (string column)
        {
            return GetAsInt (column, 0);
        }

        public int GetAsInt (string column, int defaultValue)
        {
            object v = this [column];
            if (v == null)
            {
                return defaultValue;
            }
            else if (v is long)
            {
                return (int)(long)v;
            }
            else if (v is int)
            {
                return (int)v;
            }
            else if (v is double)
            {
                return (int)(double)v;
            }
            else if (v is string)
            {
                return int.Parse ((string)v);
            }
            else
            {
                return int.Parse (v.ToString ());
            }
        }

        public double GetAsDouble (string column)
        {
            return GetAsDouble (column, 0);
        }

        public double GetAsDouble (string column, double defaultValue)
        {
            object v = this [column];
            if (v == null)
            {
                return defaultValue;
            }
            else if (v is long)
            {
                return (double)(long)v;
            }
            else if (v is int)
            {
                return (double)(int)v;
            }
            else if (v is double)
            {
                return (double)v;
            }
            else if (v is string)
            {
                return double.Parse ((string)v);
            }
            else
            {
                return double.Parse (v.ToString ());
            }
        }
    }

    public class DataTable
    {
        public DataTable ()
        {
            Columns = new List<string> ();
            Rows = new List<DataRow> ();
        }

        public List<string> Columns { get; set; }

        public List<DataRow> Rows { get; set; }
        
        public DataRow this [int row] {
            get {
                return Rows [row];
            }
        }

        public void AddRow (object[] values)
        {
            if (values.Length != Columns.Count)
            {
                throw new IndexOutOfRangeException ("The number of values in the row must match the number of column");
            }

            var row = new DataRow ();
            for (int i = 0; i < values.Length; i++)
            {
                row [Columns [i]] = values [i];
            }

            Rows.Add (row);
        }
    }

    public static class SQLExtension
    {
        public static string SQLFormat (this string str, params object[] ps)
        {
            var v = from p in ps select Convert (p);

            return string.Format (str, v.ToArray ());
        }

        public static string Convert (object v)
        {
            if (v == null)
            {
                return "NULL";
            }
            else if (v is DateTime)
            {
                return ((DateTime)v).ToBinary ().ToString ();
            }
            else if (v is string)
            {
                return "'" + Escape ((string)v) + "'";
            }
            else
            {
                return v.ToString ();
            }
        }

        public static string Escape (string v)
        {
            return v.Replace ("\\", "\\\\").Replace ("\"", "\\\"").Replace ("'", "\\'");
        }
    }
}