Pascal Data Objects


The TPDORowKeyStrings type is just a TStringList. Fetched rows returned in this structure are keyed: Column Name / Value. So if a query returns five columns, the TPDORowKeyStrings variable will be a list of five strings.

There are many benefits to this:

  • Its known that all fields are strings
  • Many functions and controls accept TStringLists natively
  • The columns can be sorted within the list
  • Field values can be retrieved by the column name
  • Field values can be retrieved by the column position in the query
  • Column counts are built-in via TStringList.count
  • Column names can be returned by index or field value
  • and others


This structure is an object that is essentially an array of TPDORowKeyStrings (TStringLists). The TPDO.fetch_all method can return an entire result set and place it into this structure.

Both TPDORowKeyStrings and TPDORowSetKeyStrings objects must be instanciated and freed.