public List <DcColumn> LoadSchema() // Table object is created to store all necessary parameters which are individual for each table
{
TableCsv table = this;
List <DcColumn> columns = new List <DcColumn>();
if (table.FilePath == null || !File.Exists(table.FilePath)) // File might not have been created (e.g., if it is an export file)
{
return(columns);
}
// TODO: We should not use connection - use TableReader/TableWriter where necessary (connection is hidden within them)
ConnectionCsv connection = new ConnectionCsv();
connection.OpenReader(table);
List <string> names = connection.ReadColumns();
List <string[]> sampleRows = connection.ReadSampleValues();
for (int i = 0; i < names.Count; i++)
{
string columnName = names[i];
DcTable type = this.Schema.GetPrimitiveType("String");
ColumnCsv column = (ColumnCsv)Space.CreateColumn(DcSchemaKind.Csv, columnName, table, type, false);
//DcColumn column = Space.CreateColumn(columnName, table, type, false);
columns.Add(column);
// Properties specific to this column type
column.ColumnIndex = i;
var values = new List <string>();
foreach (var row in sampleRows)
{
values.Add(row[i]);
}
column.SampleValues = values;
}
connection.CloseReader();
return(columns);
}
public ConnectionCsv connection; // Connection object for access to the native engine functions
// Use name of the connection for setting schema name
#endregion
#region Schema methods
public List <DcColumn> LoadSchema(TableCsv table) // Table object is created to store all necessary parameters which are individual for each table
{
List <DcColumn> columns = new List <DcColumn>();
if (table.FilePath == null || !File.Exists(table.FilePath)) // File might not have been created (e.g., if it is an export file)
{
return(columns);
}
connection.OpenReader(table);
List <string> names = connection.ReadColumns();
List <string[]> sampleRows = connection.ReadSampleValues();
for (int i = 0; i < names.Count; i++)
{
string columnName = names[i];
DcTable type = this.GetPrimitiveType("String");
ColumnCsv column = (ColumnCsv)Space.CreateColumn(DcSchemaKind.Csv, columnName, table, type, false);
column.ColumnIndex = i;
columns.Add(column);
var values = new List <string>();
foreach (var row in sampleRows)
{
values.Add(row[i]);
}
column.SampleValues = values;
}
//AddTable(table, null, null);
connection.CloseReader();
return(columns);
}
