public string GenerateSqlString(ISqlStatement sqlStatement)
{
if (sqlStatement == null)
{
return(null);
}
var sql = GenerateFrom(sqlStatement.Find(StatementKeys.From));
AddSelect(ref sql, sqlStatement.Find(StatementKeys.Select));
AddWhere(ref sql, sqlStatement.Find(StatementKeys.Where));
AddGroupBy(ref sql, sqlStatement.Find(StatementKeys.GroupBy));
AddHaving(ref sql, sqlStatement.Find(StatementKeys.Having));
AddOrderBy(ref sql, sqlStatement.Find(StatementKeys.OrderBy));
return(sql);
}