private void appendAliasedColumn(StringBuilder sb,String colName,String tAlias){
  if (tAlias != null) {
    sb.append(tAlias);
    sb.append(".");
  }
  sb.append("\"");
  sb.append(colName);
  sb.append("\"");
}

private void appendAliasedColumn ( StringBuilder sb , String colName , String tAlias ) { if ( tAlias != null ) { sb . append ( tAlias ) ; sb . append ( "." ) ; } sb . append ( "\"" ) ; sb . append ( colName ) ; sb . append ( "\"" ) ; }
appends a quoted column name , prepending a table alias if necessary
