mcs/class/FirebirdSql.Data.Firebird/FirebirdSql.Data.Firebird/DbSchema/FbDbSchema.cs

   1 /*
   2  *      Firebird ADO.NET Data provider for .NET and Mono
   3  *
   4  *         The contents of this file are subject to the Initial
   5  *         Developer's Public License Version 1.0 (the "License");
   6  *         you may not use this file except in compliance with the
   7  *         License. You may obtain a copy of the License at
   8  *         http://www.firebirdsql.org/index.php?op=doc&id=idpl
   9  *
  10  *         Software distributed under the License is distributed on
  11  *         an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either
  12  *         express or implied. See the License for the specific
  13  *         language governing rights and limitations under the License.
  14  *
  15  *      Copyright (c) 2002, 2005 Carlos Guzman Alvarez
  16  *      All Rights Reserved.
  17  */
  18
  19 using System;
  20 using System.Data;
  21 using System.Globalization;
  22 using System.Text;
  23 using System.Text.RegularExpressions;
  24 using System.Collections;
  25
  26 namespace FirebirdSql.Data.Firebird.DbSchema
  27 {
  28         internal abstract class FbDbSchema
  29         {
  30                 #region Fields
  31
  32                 private string schemaName;
  33
  34                 #endregion
  35
  36                 #region Constructors
  37
  38                 public FbDbSchema(string schemaName)
  39                 {
  40                         this.schemaName = schemaName;
  41                 }
  42
  43                 #endregion
  44
  45                 #region Abstract Methods
  46
  47                 protected abstract StringBuilder GetCommandText(object[] restrictions);
  48
  49                 #endregion
  50
  51                 #region Methods
  52
  53                 public virtual DataTable GetSchema(FbConnection connection, object[] restrictions)
  54                 {
  55                         restrictions = this.ParseRestrictions(restrictions);
  56
  57                         FbCommand               command = this.BuildCommand(connection, restrictions);
  58                         FbDataAdapter   adapter = new FbDataAdapter(command);
  59                         DataSet                 dataSet = new DataSet(this.schemaName);
  60
  61                         try
  62                         {
  63                                 adapter.Fill(dataSet, this.schemaName);
  64                         }
  65                         catch (Exception ex)
  66                         {
  67                                 throw new FbException(ex.Message);
  68                         }
  69                         finally
  70                         {
  71                                 adapter.Dispose();
  72                                 command.Dispose();
  73                         }
  74
  75                         TrimStringFields(dataSet.Tables[this.schemaName]);
  76
  77                         return this.ProcessResult(dataSet.Tables[this.schemaName]);
  78                 }
  79
  80                 #endregion
  81
  82                 #region Protected Methods
  83
  84                 protected FbCommand BuildCommand(FbConnection connection, object[] restrictions)
  85                 {
  86                         DataView collections = FbMetaDataCollections.GetSchema().DefaultView;
  87                         collections.RowFilter = "CollectionName = '" + this.schemaName + "'";
  88
  89                         if (collections.Count == 0)
  90                         {
  91                                 throw new NotSupportedException("Unsupported collection name.");
  92                         }
  93
  94                         if (restrictions != null &&
  95                                 restrictions.Length > (int)collections[0]["NumberOfRestrictions"])
  96                         {
  97                                 throw new InvalidOperationException("The number of specified restrictions is not valid.");
  98                         }
  99
 100                         DataView restriction = FbRestrictions.GetSchema().DefaultView;
 101                         restriction.RowFilter = "CollectionName = '" + this.schemaName + "'";
 102
 103                         if (restriction.Count != (int)collections[0]["NumberOfRestrictions"])
 104                         {
 105                                 throw new InvalidOperationException("Incorrect restriction definitions.");
 106                         }
 107
 108                         StringBuilder builder = this.GetCommandText(restrictions);
 109                         FbCommand schema = connection.CreateCommand();
 110
 111                         schema.CommandText = builder.ToString();
 112
 113                         if (connection.InnerConnection.HasActiveTransaction)
 114                         {
 115                                 schema.Transaction = connection.InnerConnection.ActiveTransaction;
 116                         }
 117
 118                         if (restrictions != null && restrictions.Length > 0)
 119                         {
 120                                 // Add parameters
 121                                 int index = 0;
 122
 123                                 for (int i = 0; i < restrictions.Length; i++)
 124                                 {
 125                                         string rname = restriction[i]["RestrictionDefault"].ToString().ToLower(CultureInfo.CurrentCulture);
 126                                         if (restrictions[i] != null &&
 127                                                 !rname.EndsWith("_catalog") &&
 128                                                 !rname.EndsWith("_schema") &&
 129                                                 rname != "table_type")
 130                                         {
 131                                                 string pname = String.Format(CultureInfo.CurrentCulture, "@p{0}", index++);
 132
 133                                                 FbParameter p = schema.Parameters.Add(pname, restrictions[i].ToString());
 134                                                 p.FbDbType = FbDbType.VarChar;
 135                                                 p.Size = 255;
 136                                         }
 137                                 }
 138                         }
 139
 140                         return schema;
 141                 }
 142
 143                 protected virtual DataTable ProcessResult(DataTable schema)
 144                 {
 145                         return schema;
 146                 }
 147
 148                 protected virtual object[] ParseRestrictions(object[] restrictions)
 149                 {
 150                         return restrictions;
 151                 }
 152
 153                 #endregion
 154
 155                 #region Private Static Methods
 156
 157                 private static void TrimStringFields(DataTable schema)
 158                 {
 159                         schema.BeginLoadData();
 160
 161                         foreach (DataRow row in schema.Rows)
 162                         {
 163                                 for (int i = 0; i < schema.Columns.Count; i++)
 164                                 {
 165                                         if (schema.Columns[i].DataType == typeof(System.String))
 166                                         {
 167                                                 row[schema.Columns[i]] = row[schema.Columns[i]].ToString().Trim();
 168                                         }
 169                                 }
 170                         }
 171
 172                         schema.EndLoadData();
 173                         schema.AcceptChanges();
 174                 }
 175
 176                 #endregion
 177         }
 178 }