Muokkaa

Jaa


Extending the Data Archive extension

The Data Archive extension provides a basic framework for archiving and backing up data as part of date compression. When you use date compression you specify a date range and all entries within the range are consolidated into a single entry, and the originals are deleted. For more information, see Compress Data with Date Compression. However, there might be value in keeping that data, so rather than deleting it, you can use the Data Archive extension to archive it for later use.

This article provides an example of how you can use the objects in the Data Archive extension so that your application can also archive data. You use the Data Archive codeunit, which is available in the System Application.

The following patterns of use are supported:

  • Store individual records by calling the SaveRecord(Record) method.
  • Store a record set by calling the SaveRecords(RecordRef) method.
  • Start recording deletions by calling the StartSubscriptionToDelete() method in the beginning of your code, and StopSubscriptionToDelete() after records have been deleted. Note that this pattern records all deletions, including those that happen in related tables and intermediate tables that might be used in the process (though temporary records aren't recorded).

Note

Recording deletions relies on the global database triggers, so for any deletions that have already been made on the relevant records, and if the change log is not active for that table, you should consider using StartSubscriptionToDelete(true) to reset the session. Resetting the session will, however, also reset the state in the object, so we recommend caution when you test or use it.

The following example illustrates these patterns.

codeunit 50000 demo
{
    trigger OnRun()
    var
        DataArchive: Codeunit "Data Archive";
    begin
        if DataArchive.DataArchiveProviderExists() then begin
            SaveSingleRecords();
            SaveRecordSet();
            DeleteAndArchiveSomeCustomers();
        end;
    end;

    local procedure SaveSingleRecords()
    var
        Customer: Record Customer;
        DataArchive: Codeunit "Data Archive";
    begin
        Customer.SetRange("Country/Region Code", 'FO');
        if Customer.FindSet() then begin
            DataArchive.Create('Our Faroese customers');
            repeat
                DataArchive.SaveRecord(Customer);
            until Customer.Next() = 0;
            DataArchive.Save();
        end;
    end;

    local procedure SaveRecordSet()
    var
        Customer: Record Customer;
        DataArchive: Codeunit "Data Archive";
        RecRef: RecordRef;
    begin
        Customer.SetRange("Country/Region Code", 'FO');
        if not Customer.IsEmpty() then begin
            DataArchive.Create('Our Faroese customers');
            RecRef.GetTable(Customer);
            DataArchive.SaveRecords(RecRef);
            DataArchive.Save();
        end;
    end;

    local procedure DeleteAndArchiveSomeCustomers()
    var
        Customer: Record Customer;
        DataArchive: Codeunit "Data Archive";
    begin
        Customer.SetRange("Country/Region Code", 'FO');
        if not Customer.IsEmpty() then begin
            DataArchive.Create('Deleted Faroese customers');
            DataArchive.StartSubscriptionToDelete();
            Customer.DeleteAll(true);
            DataArchive.StopSubscriptionToDelete();
            DataArchive.Save();
        end;
    end;
}

Methods in the Data Archive codeunit

The following table lists the methods that the Data Archive codeunit provides.

Methods Description
procedure Create(Description: Text): Integer Creates a new archive entry.
procedure CreateAndStartLoggingDeletions(Description: Text): Integer Creates a new archive entry, resets the session and starts logging all new del
procedure Open(ID: Integer) Opens an existing archive entry so more can be added to it
procedure Save() Saves and closes the currently open archive entry.
procedure DiscardChanges() Discards any additions and closes the currently open archive entry.
procedure SaveRecord(RecordVar: Variant)
procedure SaveRecord(var RecRef: RecordRef)
Saves the supplied record to the currently open archive entry.
procedure SaveRecords(var RecRef: RecordRef) Saves all records within the filters to the currently open archive entry.
procedure StartSubscriptionToDelete()
procedure StartSubscriptionToDelete(ResetSession: Boolean)
Starts subscription to the OnDatabaseDelete trigger and calls SaveRecord with any deleted record.
procedure StopSubscriptionToDelete() Stops the subscription to the OnDatabaseDelete trigger.
procedure DataArchiveProviderExists(): Boolean Informs the consumer app whether there's a provider for this interface.

The Data Archive Extension
The Microsoft_Application.app File
Extending Application Areas