mcs/class/Mono.Data.PostgreSqlClient/PgSqlTransaction.cs

   1 //
   2 // Mono.Data.PostgreSqlClient.PgSqlTransaction.cs
   3 //
   4 // Author:
   5 //   Rodrigo Moya (rodrigo@ximian.com)
   6 //   Daniel Morgan (danmorg@sc.rr.com)
   7 //
   8 // (C) Ximian, Inc. 2002
   9 //
  10
  11 // use #define DEBUG_SqlTransaction if you want to spew debug messages
  12 // #define DEBUG_SqlTransaction
  13
  14
  15 using System;
  16 using System.Data;
  17 using System.Data.Common;
  18
  19 namespace Mono.Data.PostgreSqlClient
  20 {
  21         /// <summary>
  22         /// Represents a transaction to be performed on a SQL database.
  23         /// </summary>
  24         // public sealed class PgSqlTransaction : MarshalByRefObject,
  25         //      IDbTransaction, IDisposable
  26         public sealed class PgSqlTransaction : IDbTransaction
  27         {
  28                 #region Fields
  29
  30                 private bool doingTransaction = false;
  31                 private PgSqlConnection conn = null;
  32                 private IsolationLevel isolationLevel =
  33                         IsolationLevel.ReadCommitted;
  34                 // There are only two IsolationLevel's for PostgreSQL:
  35                 //    ReadCommitted and Serializable,
  36                 // but ReadCommitted is the default
  37
  38                 #endregion
  39
  40                 #region Public Methods
  41
  42                 [MonoTODO]
  43                 public void Commit ()
  44                 {
  45                         if(doingTransaction == false)
  46                                 throw new InvalidOperationException(
  47                                         "Begin transaction was not " +
  48                                         "done earlier " +
  49                                         "thus PostgreSQL can not " +
  50                                         "Commit transaction.");
  51
  52                         PgSqlCommand cmd = new PgSqlCommand("COMMIT", conn);
  53                         cmd.ExecuteNonQuery();
  54
  55                         doingTransaction = false;
  56                 }
  57
  58                 [MonoTODO]
  59                 public void Rollback()
  60                 {
  61                         if(doingTransaction == false)
  62                                 throw new InvalidOperationException(
  63                                         "Begin transaction was not " +
  64                                         "done earlier " +
  65                                         "thus PostgreSQL can not " +
  66                                         "Rollback transaction.");
  67
  68                         PgSqlCommand cmd = new PgSqlCommand("ROLLBACK", conn);
  69                         cmd.ExecuteNonQuery();
  70
  71                         doingTransaction = false;
  72                 }
  73
  74                 // For PostgreSQL, Rollback(string) will not be implemented
  75                 // because PostgreSQL does not support Savepoints
  76                 [Obsolete]
  77                 public void Rollback(string transactionName) {
  78                         // throw new NotImplementedException ();
  79                         Rollback();
  80                 }
  81
  82                 // For PostgreSQL, Save(string) will not be implemented
  83                 // because PostgreSQL does not support Savepoints
  84                 [Obsolete]
  85                 public void Save (string savePointName) {
  86                         // throw new NotImplementedException ();
  87                 }
  88
  89                 #endregion // Public Methods
  90
  91                 #region Internal Methods to Mono.Data.PostgreSqlClient.dll Assembly
  92
  93                 internal void Begin()
  94                 {
  95                         if(doingTransaction == true)
  96                                 throw new InvalidOperationException(
  97                                         "Transaction has begun " +
  98                                         "and PostgreSQL does not " +
  99                                         "support nested transactions.");
 100
 101                         PgSqlCommand cmd = new PgSqlCommand("BEGIN", conn);
 102                         cmd.ExecuteNonQuery();
 103
 104                         doingTransaction = true;
 105                 }
 106
 107                 internal void SetIsolationLevel(IsolationLevel isoLevel)
 108                 {
 109                         String sSql = "SET TRANSACTION ISOLATION LEVEL ";
 110
 111                         switch (isoLevel) \r
 112                         {
 113                                 case IsolationLevel.ReadCommitted:
 114                                         sSql += "READ COMMITTED";
 115                                         break;
 116
 117                                 case IsolationLevel.Serializable:
 118                                         sSql += "SERIALIZABLE";
 119                                         break;
 120
 121                                 default:
 122                                         // FIXME: generate exception here
 123                                         // PostgreSQL only supports:
 124                                         //   ReadCommitted or Serializable
 125                                         break;
 126                         }
 127                         PgSqlCommand cmd = new PgSqlCommand(sSql, conn);
 128                         cmd.ExecuteNonQuery();
 129
 130                         this.isolationLevel = isoLevel;
 131                 }
 132
 133                 internal void SetConnection(PgSqlConnection connection)
 134                 {
 135                         this.conn = connection;
 136                 }
 137
 138                 #endregion // Internal Methods to System.Data.dll Assembly
 139
 140                 #region Properties
 141
 142                 IDbConnection IDbTransaction.Connection {
 143                         get {
 144                                 return Connection;
 145                         }
 146                 }
 147
 148                 public PgSqlConnection Connection       {
 149                         get {
 150                                 return conn;
 151                         }
 152                 }
 153
 154                 public IsolationLevel IsolationLevel {
 155                         get {
 156                                 return isolationLevel;
 157                         }
 158                 }
 159
 160                 internal bool DoingTransaction {
 161                         get {
 162                                 return doingTransaction;
 163                         }
 164                 }
 165
 166                 #endregion Properties
 167
 168                 #region Destructors
 169
 170                 // Destructors aka Finalize and Dispose
 171
 172                 [MonoTODO]
 173                 public void Dispose()
 174                 {
 175                         // FIXME: need to properly release resources
 176                         // Dispose(true);
 177                 }
 178
 179                 // Destructor
 180                 [MonoTODO]
 181                 // [Serializable]\r
 182                 // [ClassInterface(ClassInterfaceType.AutoDual)]
 183                 ~PgSqlTransaction() {
 184                         // FIXME: need to properly release resources
 185                         // Dispose(false);
 186                 }
 187
 188                 #endregion // Destructors
 189
 190         }
 191 }