DataSet Definition
Last updated
Last updated
A DataSet is a data container composed of tables (DataTables) that contain rows (DataRows), uses SQL queries to retrieve that data from the database, tracks changes to each columns and generated update/insert/delete statements transparently when required to write data back into the database.
Each DataRow may have one of the following RowStates:
New: the row was added to the dataSet and will be ignored on Save
EditingNew: the row was already edited and it’s prepared to be saved
Modified: an existing row was modified
NotModified: an existing row was retrieved from the database
Deleted: the row was marked as deleted, will be deleted only at Save
None: the row was not added to the collection; the row is detached
For updateable DataSets, the tables must be arranged in the same order, in which the primary-key inserts are done.
For the Delete operation, the DataSet will do the action in the reverse order.
Reordering can be done on the second tab (Tables) of the DataSet-Editor (shortcut TDS), using Drag&Drop.