// build the SELECT clause
string BuildSelectClause()
{
StringBuilder sb = new StringBuilder();
foreach (QueryField field in QueryFields)
{
if (field.Output)
{
// add separator
if (sb.Length > 0)
{
sb.Append(",\r\n\t");
}
// add field expression ("table.column" or "colexpr")
string item = field.GetFullName(GroupBy);
sb.Append(item);
// add alias (use brackets to contain spaces, reserved words, etc)
if (!string.IsNullOrEmpty(field.Alias))
{
sb.AppendFormat(" AS {0}", OleDbSchema.BracketName(field.Alias));
}
}
}
return(sb.ToString());
}
/// <summary>
/// Gets the full field name, including the parent table name and brackets.
/// </summary>
/// <returns>The full field name.</returns>
public string GetFullName()
{
// return table.column string
if (Column == "*" || _table.Columns.Contains(Column))
{
return(string.Format("{0}.{1}",
OleDbSchema.GetFullTableName(_table),
OleDbSchema.BracketName(Column)));
}
// column is not part of a table (e.g. expression)
return(OleDbSchema.BracketName(Column));
}