mcs/class/Mono.Data.DB2Client/Mono.Data.Db2Client/DB2ClientDataReader.cs

   1
   2 //
   3 // Permission is hereby granted, free of charge, to any person obtaining
   4 // a copy of this software and associated documentation files (the
   5 // "Software"), to deal in the Software without restriction, including
   6 // without limitation the rights to use, copy, modify, merge, publish,
   7 // distribute, sublicense, and/or sell copies of the Software, and to
   8 // permit persons to whom the Software is furnished to do so, subject to
   9 // the following conditions:
  10 //
  11 // The above copyright notice and this permission notice shall be
  12 // included in all copies or substantial portions of the Software.
  13 //
  14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  18 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  19 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  20 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21 //
  22 #region Licence\r
  23         /// DB2DriverCS - A DB2 driver for .Net\r
  24         /// Copyright 2003 By Christopher Bockner\r
  25         /// Released under the terms of the MIT/X11 Licence\r
  26         /// Please refer to the Licence.txt file that should be distributed with this package\r
  27         /// This software requires that DB2 client software be installed correctly on the machine\r
  28         /// (or instance) on which the driver is running.  \r
  29 #endregion\r
  30 using System;\r
  31 using System.Data;\r
  32 using System.Runtime.InteropServices;\r
  33 using System.Globalization;\r
  34 using System.Text;\r
  35 \r
  36 namespace DB2ClientCS\r
  37 {\r
  38         /// <summary>\r
  39         /// Summary description for DB2ClientDataReader.\r
  40         /// DB2ClientDataReader. \r
  41         /// </summary>\r
  42         public class DB2ClientDataReader : IDataReader\r
  43         {\r
  44                 internal DataTable rs;                  //Our result set is a datatable\r
  45                 internal DB2ClientConnection db2Conn; //The connection we're working with\r
  46                 internal IntPtr hwndStmt;               //The statement handle returning the results\r
  47                 private int row=-1;                             //Row pointer\r
  48                 private int numCols=0;\r
  49                 \r
  50                 #region Constructors and destructors\r
  51                 /// <summary>\r
  52                 /// \r
  53                 /// </summary>\r
  54                 /// <param name="con"></Connection object to DB2>\r
  55                 /// <param name="com"></Command object>\r
  56                 internal DB2ClientDataReader(DB2ClientConnection con, DB2ClientCommand com)\r
  57                 {\r
  58                         db2Conn = con;\r
  59                         hwndStmt = com.statementHandle;    //We have access to the results through the statement handle\r
  60 \r
  61                         short sqlRet;\r
  62 \r
  63                         DB2ClientUtils util = new DB2ClientUtils();\r
  64                         rs = new DataTable();\r
  65                         \r
  66                         sqlRet = DB2ClientPrototypes.SQLNumResultCols(hwndStmt, ref numCols);\r
  67                         util.DB2CheckReturn(sqlRet, DB2ClientConstants.SQL_HANDLE_STMT, hwndStmt, "DB2ClientDataReader - SQLNumResultCols");\r
  68 \r
  69                         byte[][] dbVals = new byte[(int)numCols][];\r
  70                         IntPtr[] sqlLen_or_IndPtr = new IntPtr[numCols];\r
  71 \r
  72                         PrepareResults(dbVals, sqlLen_or_IndPtr);\r
  73                         FetchResults(dbVals, sqlLen_or_IndPtr, rs);\r
  74                         isClosed = false;\r
  75                 }\r
  76                 /// <summary>\r
  77                 /// Constructor for use with prepared statements\r
  78                 /// </summary>\r
  79                 /// \r
  80                 internal DB2ClientDataReader(DB2ClientConnection con, DB2ClientCommand com, bool prepared)\r
  81                 {\r
  82                         db2Conn = con;\r
  83                         hwndStmt = com.statementHandle;    //We have access to the results through the statement handle\r
  84 \r
  85                         short sqlRet;\r
  86 \r
  87                         DB2ClientUtils util = new DB2ClientUtils();\r
  88                         rs = new DataTable();\r
  89                         \r
  90                         sqlRet = DB2ClientPrototypes.SQLNumResultCols(hwndStmt, ref numCols);\r
  91                         util.DB2CheckReturn(sqlRet, DB2ClientConstants.SQL_HANDLE_STMT, hwndStmt, "DB2ClientDataReader - SQLNumResultCols");\r
  92 \r
  93                         byte[][] dbVals = new byte[(int)numCols][];\r
  94                         IntPtr[] sqlLen_or_IndPtr = new IntPtr[numCols];\r
  95 \r
  96 \r
  97                         PrepareResults(dbVals, sqlLen_or_IndPtr);\r
  98                         FetchResults(dbVals, sqlLen_or_IndPtr, rs);\r
  99                         isClosed = false;\r
 100                 }\r
 101 \r
 102                 public void Dispose()\r
 103                 {\r
 104                         Close();\r
 105                 }\r
 106                 #endregion\r
 107                 #region Properties\r
 108                 #region Depth property \r
 109                 ///\r
 110                 ///Depth of nesting for the current row, need to figure out what this translates into \r
 111                 ///with DB2.\r
 112                 ///\r
 113                 private int depth = 0;\r
 114                 public int Depth\r
 115                 {\r
 116                         get\r
 117                         {\r
 118                                 return depth;\r
 119                         }\r
 120                 }\r
 121                 #endregion\r
 122                 #region IsClosed property\r
 123                 /// <summary>\r
 124                 /// True if the reader is closed.\r
 125                 /// </summary>\r
 126                 private bool isClosed = true;\r
 127                 public bool IsClosed\r
 128                 {\r
 129                         get\r
 130                         {\r
 131                                 return isClosed;\r
 132                         }\r
 133                 }\r
 134                 #endregion\r
 135                 #region RecordsAffected property\r
 136                 ///\r
 137                 /// Number of records affected by this operation.  Will be zero until we close the \r
 138                 /// reader\r
 139                 /// \r
 140                 private int recordsAffected = 0;\r
 141                 public int RecordsAffected\r
 142                 {\r
 143                         get\r
 144                         {\r
 145                                 return recordsAffected;\r
 146                         }\r
 147                 }\r
 148                 #endregion\r
 149                 #endregion\r
 150                 #region Methods\r
 151                 #region Close method\r
 152                 ///\r
 153                 ///\r
 154                 public void Close()\r
 155                 {\r
 156                         if (rs != null) \r
 157                         {\r
 158                                 recordsAffected = rs.Rows.Count;\r
 159                                 rs.Dispose();\r
 160                                 rs = null;\r
 161                                 isClosed=true;\r
 162                         }\r
 163                 }\r
 164                 #endregion\r
 165                 #region GetSchemaTable \r
 166                 ///\r
 167                 /// We'll return an empty table for now...ughh this one will be tedious to write\r
 168                 /// \r
 169                 public DataTable GetSchemaTable()\r
 170                 {\r
 171                         throw new DB2ClientException ("TBD");\r
 172                 }\r
 173                 #endregion\r
 174                 #region NextResult \r
 175                 ///\r
 176                 /// Ummm is this related to SQLBulkOperations stuff..?\r
 177                 /// \r
 178                 public bool NextResult()\r
 179                 {\r
 180                         throw new DB2ClientException("To be done");\r
 181 \r
 182                 //Deferring the meat of this until the batch stuff is implemented\r
 183                 }\r
 184                 #endregion\r
 185                 #region Read\r
 186                 ///\r
 187                 /// Apparently, this function does nothing other than tell you if you can move to the \r
 188                 /// next row in the resultset.  I have to move the fetching stuff elswhere...\r
 189                 /// \r
 190                 public bool Read()\r
 191                 {\r
 192                         if (isClosed) return false;\r
 193                         row++;\r
 194                         //do something with the fetched data now...\r
 195                         if(row < rs.Rows.Count)\r
 196                                 return true;\r
 197                         else\r
 198                                 return false;\r
 199                         \r
 200                 }\r
 201                 #endregion\r
 202 \r
 203                 #region Describe/Bind/Fetch functions\r
 204                 ///\r
 205                 ///Broke these out so that we can use different paths for Immediate executions and Prepared executions\r
 206                 /// <summary>\r
 207                 /// Does the describe and bind steps for the query result set.  Called for both immediate and prepared queries. \r
 208                 /// </summary>\r
 209                 private void PrepareResults(byte[][] dbVals, IntPtr[] sqlLen_or_IndPtr)\r
 210                 {\r
 211                         short sqlRet;\r
 212                         StringBuilder colName = new StringBuilder(18);\r
 213                         short colNameMaxLength=18;\r
 214                         IntPtr colNameLength=IntPtr.Zero;\r
 215                         IntPtr sqlDataType=IntPtr.Zero;\r
 216                         IntPtr colSize=IntPtr.Zero;\r
 217                         IntPtr scale=IntPtr.Zero;\r
 218                         IntPtr nullable=IntPtr.Zero;\r
 219                         DB2ClientUtils util = new DB2ClientUtils();\r
 220                         for (ushort i=1; i<=numCols; i++) \r
 221                         {\r
 222                                 sqlRet = DB2ClientPrototypes.SQLDescribeCol(hwndStmt, i, colName, colNameMaxLength, colNameLength, ref sqlDataType, ref colSize, ref scale, ref nullable);\r
 223                                 util.DB2CheckReturn(sqlRet, DB2ClientConstants.SQL_HANDLE_STMT, hwndStmt, "DB2ClientDataReader - SQLDescribeCol");\r
 224                                 ///At this point I have the data type information as well, but for now I will insert the data as\r
 225                                 ///Ansi strings and see how it goes.  Maybe we can speed things up later...\r
 226                                 ///\r
 227                                 rs.Columns.Add(colName.ToString());\r
 228 \r
 229                                 sqlLen_or_IndPtr[i-1] = new IntPtr();\r
 230                                 dbVals[i-1] = new byte[(int)colSize];\r
 231 \r
 232 \r
 233                                 try \r
 234                                 {\r
 235                                         switch ((int)sqlDataType) \r
 236                                         {\r
 237                                                 case DB2ClientConstants.SQL_DECIMAL:    //These types are treated as SQL_C_CHAR for binding purposes\r
 238                                                 case DB2ClientConstants.SQL_TYPE_DATE:\r
 239                                                 case DB2ClientConstants.SQL_TYPE_TIME:\r
 240                                                 case DB2ClientConstants.SQL_TYPE_TIMESTAMP:\r
 241                                                 case DB2ClientConstants.SQL_VARCHAR:\r
 242                                                         sqlRet = DB2ClientPrototypes.SQLBindCol(hwndStmt, i, DB2ClientConstants.SQL_C_CHAR, dbVals[i-1],(short)colSize+1, (int)sqlLen_or_IndPtr[i-1]);\r
 243                                                         break;\r
 244                                                 default:\r
 245                                                         sqlRet = DB2ClientPrototypes.SQLBindCol(hwndStmt, i, (short)sqlDataType, dbVals[i-1],(short)colSize+1, (int)sqlLen_or_IndPtr[i-1]);\r
 246                                                         break;\r
 247                                         }\r
 248                                         util.DB2CheckReturn(sqlRet, DB2ClientConstants.SQL_HANDLE_STMT, hwndStmt, "DB2ClientDataReader - SQLBindCol");\r
 249                                 }\r
 250                                 catch(DB2ClientException e) \r
 251                                 {\r
 252                                         System.Console.Write(e.Message);\r
 253                                 }\r
 254                         }\r
 255                         isClosed = false;\r
 256                 }\r
 257 /// <summary>\r
 258 /// FetchResults does  what it says.\r
 259 /// </summary>\r
 260 /// <param name="dbVals"></param>\r
 261 /// <param name="sqlLen_or_IndPtr"></param>\r
 262 /// <param name="rs"></param>\r
 263                 private void FetchResults(byte[][] dbVals, IntPtr[] sqlLen_or_IndPtr, DataTable rs) \r
 264                 {\r
 265                         short sqlRet = 0;\r
 266                         DB2ClientUtils util = new DB2ClientUtils();\r
 267 \r
 268                         sqlRet = DB2ClientPrototypes.SQLFetch(hwndStmt);\r
 269                         util.DB2CheckReturn(sqlRet, DB2ClientConstants.SQL_HANDLE_STMT, hwndStmt, "DB2ClientDataReader - SQLFetch 1");\r
 270 \r
 271                         while(sqlRet != DB2ClientConstants.SQL_NO_DATA_FOUND)\r
 272                         {\r
 273                                 DataRow newRow = rs.NewRow();\r
 274                                 for (short y=1;y<=numCols;y++) \r
 275                                         newRow[y-1] = System.Text.Encoding.Default.GetString(dbVals[y-1]);\r
 276 \r
 277                                 rs.Rows.Add(newRow);\r
 278                                 sqlRet = DB2ClientPrototypes.SQLFetch(hwndStmt);\r
 279                                 util.DB2CheckReturn(sqlRet, DB2ClientConstants.SQL_HANDLE_STMT, hwndStmt, "DB2ClientDataReader - SQLFetch 2");\r
 280                         }               \r
 281                 }\r
 282                 #endregion\r
 283 \r
 284                 #region IDataRecord Interface\r
 285                 ///Code for the IDataRecord interface\r
 286                 ///\r
 287                 #region FieldCount\r
 288                 ///\r
 289                 ///\r
 290                 private int fieldCount = -1;\r
 291                 public int FieldCount\r
 292                 {\r
 293                         get\r
 294                         {\r
 295                                 if (IsClosed)\r
 296                                         fieldCount = 0;\r
 297                                 else\r
 298                                         fieldCount = rs.Columns.Count;\r
 299                                 return fieldCount;\r
 300                         }\r
 301                 }\r
 302                 #endregion\r
 303                 #region Item accessors\r
 304                 public object this[string name]\r
 305                 {\r
 306                         get\r
 307                         {\r
 308                                 return rs.Rows[row][name];\r
 309                         }\r
 310                 }\r
 311                 public object this[int col]\r
 312                 {\r
 313                         get\r
 314                         {\r
 315                                 return rs.Rows[row][col];\r
 316                         }\r
 317                 }\r
 318                 #endregion\r
 319                 #region GetBoolean method\r
 320                 ///\r
 321                 ///Use the Convert class for all of these returns\r
 322                 ///\r
 323                 public bool GetBoolean(int col)\r
 324                 {\r
 325                         return Convert.ToBoolean(this[col]);\r
 326                 }\r
 327                 #endregion\r
 328                 #region GetByte\r
 329                 ///\r
 330                 ///GetByte\r
 331                 ///\r
 332                 public byte GetByte(int col)\r
 333                 {\r
 334                         return Convert.ToByte(this[col]);\r
 335                 }\r
 336                 #endregion\r
 337                 #region GetBytes\r
 338                 ///\r
 339                 ///  GetBytes, return a stream of bytes\r
 340                 ///\r
 341                 public long GetBytes(int col, long fieldOffset, byte[] buffer, int bufferOffset, int length)\r
 342                 {\r
 343                         //Hmm... How shall we deal with this one?  \r
 344                         return 0;\r
 345                 }\r
 346                 #endregion\r
 347                 #region GetChar\r
 348                 ///\r
 349                 ///GetChar, return column as a char\r
 350                 ///\r
 351                 public char GetChar(int col)\r
 352                 {\r
 353                         return Convert.ToChar(this[col]);\r
 354                 }\r
 355                 #endregion\r
 356                 #region GetChars\r
 357                 ///\r
 358                 ///GetChars, returns char array\r
 359                 ///\r
 360                 public long GetChars(int col, long fieldOffset, char[] buffer, int bufferOffset, int length)\r
 361                 {\r
 362                         //Again, not sure how I'll deal with this just yet\r
 363                         return 0;\r
 364                 }\r
 365                 #endregion\r
 366                 #region GetData\r
 367                 ///\r
 368                 /// GetData method\r
 369                 /// \r
 370                 public IDataReader GetData(int col)\r
 371                 {\r
 372                         //Have to research this one, not quite sure what the docs mean\r
 373                         //DB2 does have some structured data types, is that what this is for?\r
 374                         throw new DB2ClientException("Not yet supported.");\r
 375                 }\r
 376                 #endregion\r
 377                 #region GetDataTypeName\r
 378                 ///\r
 379                 ///GetDataTypeName return the type of data\r
 380                 ///\r
 381                 public string GetDataTypeName(int col)\r
 382                 {\r
 383                         //I could check the meta data as a starting point for this one, but until I implement \r
 384                         //returning the result sets, I'm not exactly sure what info I'll have, so this function\r
 385                         //waits until then...\r
 386                         throw new DB2ClientException("Not yet implemented");\r
 387                 }\r
 388                 #endregion\r
 389                 #region GetDateTime\r
 390                 ///\r
 391                 /// GetDateTime method\r
 392                 /// \r
 393                 public string NewGetDateTime(int col)\r
 394                 {\r
 395                         return Convert.ToString(this[col]);\r
 396                 }\r
 397                 public DateTime GetDateTime(int col)\r
 398                 {\r
 399                         return Convert.ToDateTime(this[col]);\r
 400                 }\r
 401                 #endregion\r
 402                 #region GetDecimal\r
 403                 ///\r
 404                 ///GetDecimal method\r
 405                 ///\r
 406                 public decimal GetDecimal(int col)\r
 407                 {\r
 408                         return Convert.ToDecimal(this[col]);\r
 409                 }\r
 410                 #endregion\r
 411                 #region GetDouble \r
 412                 ///\r
 413                 /// GetDouble \r
 414                 /// \r
 415                 public double GetDouble(int col)\r
 416                 {\r
 417                         return Convert.ToDouble(this[col]);\r
 418                 }\r
 419                 #endregion\r
 420                 #region GetFieldType\r
 421                 ///\r
 422                 /// Type GetFieldType\r
 423                 ///\r
 424                 public Type GetFieldType(int col)\r
 425                 {\r
 426                         //Again need more research here\r
 427                         return typeof(int);\r
 428                 }\r
 429                 #endregion\r
 430                 #region GetFloat\r
 431                 ///\r
 432                 /// GetFloat\r
 433                 /// \r
 434                 public float GetFloat(int col)\r
 435                 {\r
 436                         return (float) Convert.ToDouble(this[col].ToString(),new CultureInfo("en-US").NumberFormat);\r
 437                 }\r
 438                 #endregion\r
 439                 #region GetGuid\r
 440                 ///\r
 441                 /// GetGuid\r
 442                 /// \r
 443                 public Guid GetGuid(int col)\r
 444                 {\r
 445                         // a Guid is a 128 bit unique value.  Could be like a GENERATE UNIQUE in DB2\r
 446                         // as usual, need more research\r
 447                         throw new DB2ClientException("TBD");\r
 448                 }\r
 449                 #endregion\r
 450                 #region The GetInt?? series\r
 451                 ///\r
 452                 ///GetInt16\r
 453                 ///\r
 454                 public short GetInt16(int col)\r
 455                 {\r
 456                         return Convert.ToInt16(this[col]);\r
 457                 }\r
 458                 ///\r
 459                 ///GetInt32\r
 460                 ///\r
 461                 public int GetInt32(int col)\r
 462                 {\r
 463                         return Convert.ToInt32(this[col]);\r
 464                 }\r
 465                 ///\r
 466                 ///GetInt64\r
 467                 ///\r
 468                 public long GetInt64(int col)\r
 469                 {\r
 470                         return Convert.ToInt64(this[col]);\r
 471                 }\r
 472                 #endregion\r
 473                 #region GetName\r
 474                 ///\r
 475                 ///GetName, returns the name of the field\r
 476                 ///\r
 477                 public string GetName(int col)\r
 478                 {\r
 479                         return (rs.Columns[col].ColumnName);\r
 480                 }\r
 481                 #endregion\r
 482                 #region GetOrdinal\r
 483                 ///\r
 484                 /// GetOrdinal, return the index of the named column\r
 485                 /// \r
 486                 public int GetOrdinal(string name)\r
 487                 {\r
 488                         return rs.Columns[name].Ordinal;\r
 489                 }\r
 490                 #endregion\r
 491                 #region GetString\r
 492                 ///\r
 493                 /// GetString returns a string\r
 494                 /// \r
 495                 public string GetString(int col)\r
 496                 {\r
 497                         return Convert.ToString(this[col]);\r
 498                 }\r
 499                 #endregion\r
 500 \r
 501                 #region GetLobLocator\r
 502                 ///\r
 503                 ///Returns a LOB Locator class\r
 504                 ///\r
 505                 //DB2ClientLOBLocator GetLobLocator(int col)\r
 506                 //{\r
 507 \r
 508                 #endregion\r
 509 \r
 510         \r
 511                 #region GetValue\r
 512                 ///\r
 513                 /// GetVCalue, returns an object\r
 514                 /// \r
 515                 public object GetValue(int col)\r
 516                 {\r
 517                         return this[col];\r
 518                 }\r
 519                 #endregion\r
 520                 #region GetValues\r
 521                 ///\r
 522                 /// GetValues returns all columns in the row through the argument, and the number of columns in the return value\r
 523                 /// \r
 524                 public int GetValues(object[] values)\r
 525                 {\r
 526                         int numCols = FieldCount;\r
 527                         if (values.Length<numCols)\r
 528                                 throw new DB2ClientException("GetValues argument too small for number of columns in row.");\r
 529                         for (int i = 0; i<=numCols; i++)\r
 530                           values[i] = this[i];\r
 531                         return numCols;\r
 532                 }\r
 533                 #endregion\r
 534                 #region IsDBNull\r
 535                 ///\r
 536                 /// IsDBNull Is the column null\r
 537                 /// \r
 538                 public bool IsDBNull(int col)\r
 539                 {\r
 540                         //Proper implementation once I get the SQLDescribe/SQLBind/SQLFetch stuff in place\r
 541                         return false;\r
 542                 }\r
 543                 #endregion\r
 544 \r
 545                 #endregion  ///For IDataRecord\r
 546         }\r
 547 \r
 548 }\r
 549 #endregion