Mono.Data.Sqlite.SqliteConnection.Schema_ViewColumns C# (CSharp) Method

    private DataTable Schema_ViewColumns(string strCatalog, string strView, string strColumn)
    {
      DataTable tbl = new DataTable("ViewColumns");
      DataRow row;
      string strSql;
      int n;
      DataRow schemaRow;
      DataRow viewRow;

      tbl.Locale = CultureInfo.InvariantCulture;
      tbl.Columns.Add("VIEW_CATALOG", typeof(string));
      tbl.Columns.Add("VIEW_SCHEMA", typeof(string));
      tbl.Columns.Add("VIEW_NAME", typeof(string));
      tbl.Columns.Add("VIEW_COLUMN_NAME", typeof(String));
      tbl.Columns.Add("TABLE_CATALOG", typeof(string));
      tbl.Columns.Add("TABLE_SCHEMA", typeof(string));
      tbl.Columns.Add("TABLE_NAME", typeof(string));
      tbl.Columns.Add("COLUMN_NAME", typeof(string));
      tbl.Columns.Add("ORDINAL_POSITION", typeof(int));
      tbl.Columns.Add("COLUMN_HASDEFAULT", typeof(bool));
      tbl.Columns.Add("COLUMN_DEFAULT", typeof(string));
      tbl.Columns.Add("COLUMN_FLAGS", typeof(long));
      tbl.Columns.Add("IS_NULLABLE", typeof(bool));
      tbl.Columns.Add("DATA_TYPE", typeof(string));
      tbl.Columns.Add("CHARACTER_MAXIMUM_LENGTH", typeof(int));
      tbl.Columns.Add("NUMERIC_PRECISION", typeof(int));
      tbl.Columns.Add("NUMERIC_SCALE", typeof(int));
      tbl.Columns.Add("DATETIME_PRECISION", typeof(long));
      tbl.Columns.Add("CHARACTER_SET_CATALOG", typeof(string));
      tbl.Columns.Add("CHARACTER_SET_SCHEMA", typeof(string));
      tbl.Columns.Add("CHARACTER_SET_NAME", typeof(string));
      tbl.Columns.Add("COLLATION_CATALOG", typeof(string));
      tbl.Columns.Add("COLLATION_SCHEMA", typeof(string));
      tbl.Columns.Add("COLLATION_NAME", typeof(string));
      tbl.Columns.Add("PRIMARY_KEY", typeof(bool));
      tbl.Columns.Add("EDM_TYPE", typeof(string));
      tbl.Columns.Add("AUTOINCREMENT", typeof(bool));
      tbl.Columns.Add("UNIQUE", typeof(bool));

      if (String.IsNullOrEmpty(strCatalog)) strCatalog = "main";

      string master = (String.Compare(strCatalog, "temp", true, CultureInfo.InvariantCulture) == 0) ? _tempmasterdb : _masterdb;
      
      tbl.BeginLoadData();

      using (SqliteCommand cmdViews = new SqliteCommand(String.Format(CultureInfo.InvariantCulture, "SELECT * FROM [{0}].[{1}] WHERE [type] LIKE 'view'", strCatalog, master), this))
      using (SqliteDataReader rdViews = cmdViews.ExecuteReader())
      {
        while (rdViews.Read())
        {
          if (String.IsNullOrEmpty(strView) || String.Compare(strView, rdViews.GetString(2), true, CultureInfo.InvariantCulture) == 0)
          {
            using (SqliteCommand cmdViewSelect = new SqliteCommand(String.Format(CultureInfo.InvariantCulture, "SELECT * FROM [{0}].[{1}]", strCatalog, rdViews.GetString(2)), this))
            {
              strSql = rdViews.GetString(4).Replace('\r', ' ').Replace('\n', ' ').Replace('\t', ' ');
              n = CultureInfo.InvariantCulture.CompareInfo.IndexOf(strSql, " AS ", CompareOptions.IgnoreCase);
              if (n < 0)
                continue;

              strSql = strSql.Substring(n + 4);

              using (SqliteCommand cmd = new SqliteCommand(strSql, this))
              using (SqliteDataReader rdViewSelect = cmdViewSelect.ExecuteReader(CommandBehavior.SchemaOnly))
              using (SqliteDataReader rd = (SqliteDataReader)cmd.ExecuteReader(CommandBehavior.SchemaOnly))
              using (DataTable tblSchemaView = rdViewSelect.GetSchemaTable(false, false))
              using (DataTable tblSchema = rd.GetSchemaTable(false, false))
              {
                for (n = 0; n < tblSchema.Rows.Count; n++)
                {
                  viewRow = tblSchemaView.Rows[n];
                  schemaRow = tblSchema.Rows[n];

                  if (String.Compare(viewRow[SchemaTableColumn.ColumnName].ToString(), strColumn, true, CultureInfo.InvariantCulture) == 0
                    || strColumn == null)
                  {
                    row = tbl.NewRow();

                    row["VIEW_CATALOG"] = strCatalog;
                    row["VIEW_NAME"] = rdViews.GetString(2);
                    row["TABLE_CATALOG"] = strCatalog;
                    row["TABLE_SCHEMA"] = schemaRow[SchemaTableColumn.BaseSchemaName];
                    row["TABLE_NAME"] = schemaRow[SchemaTableColumn.BaseTableName];
                    row["COLUMN_NAME"] = schemaRow[SchemaTableColumn.BaseColumnName];
                    row["VIEW_COLUMN_NAME"] = viewRow[SchemaTableColumn.ColumnName];
                    row["COLUMN_HASDEFAULT"] = (viewRow[SchemaTableOptionalColumn.DefaultValue] != DBNull.Value);
                    row["COLUMN_DEFAULT"] = viewRow[SchemaTableOptionalColumn.DefaultValue];
                    row["ORDINAL_POSITION"] = viewRow[SchemaTableColumn.ColumnOrdinal];
                    row["IS_NULLABLE"] = viewRow[SchemaTableColumn.AllowDBNull];
                    row["DATA_TYPE"] = viewRow["DataTypeName"]; // SqliteConvert.DbTypeToType((DbType)viewRow[SchemaTableColumn.ProviderType]).ToString();
                    row["EDM_TYPE"] = SqliteConvert.DbTypeToTypeName((DbType)viewRow[SchemaTableColumn.ProviderType]).ToString().ToLower(CultureInfo.InvariantCulture);
                    row["CHARACTER_MAXIMUM_LENGTH"] = viewRow[SchemaTableColumn.ColumnSize];
                    row["TABLE_SCHEMA"] = viewRow[SchemaTableColumn.BaseSchemaName];
                    row["PRIMARY_KEY"] = viewRow[SchemaTableColumn.IsKey];
                    row["AUTOINCREMENT"] = viewRow[SchemaTableOptionalColumn.IsAutoIncrement];
                    row["COLLATION_NAME"] = viewRow["CollationType"];
                    row["UNIQUE"] = viewRow[SchemaTableColumn.IsUnique];
                    tbl.Rows.Add(row);
                  }
                }
              }
            }
          }
        }
      }

      tbl.EndLoadData();
      tbl.AcceptChanges();

      return tbl;
    }