Prepare Stamps

... for tracking data changes

trackin data changes?

By adding a __GlobalStamp field to a table, when a record is created or updated, it's __GlobalStamp field value will be set to the value of an auto incremental stamp global to the database.

example:
you create a Company C record: global stamp 1
you create an Employe A record: global stamp 2
you change Employe A name: global stamp 3 (no more 2 for the record)
you change a Company C record bale: global stamp 4
you create an Employe B record: global stamp 5
-> you have Company C with __GlobalStamps=4, Employe A with __GlobalStamp=3, Employe B with __GlobalStamp=5

So you could using ORDA query or REST ($filter) on each tables to get the data changes since a previous value of this global stamp. For instance the filter used to request the data could be __GlobalStamp > 42

To track deleted records, records that could no more view in tables, we need a cemetery that contains all table id/names and primary key values of deleted records. We create a table named __DeletedRecords , that could be consulted like any other tables, here using __Stamp if we want to see new deleted records since a previous value of global stamp.

Setup

First create an instance

var $prepare : cs.PrepareStamps
$prepare:=cs.PrepareStamps.new()

Verify

To verify that all is ok

var $status : Boolean
$status:=$prepare.verify()

To verify for a selection of tables

var $status : Boolean
$status:=$prepare.verify(New collection("table1"; "table2"))

Create/Modify

To create all missing fields and deleted record table

$status:=$prepare.run()

To create all missing fields of selected table and deleted record table

$status:=$prepare.run(New collection("table1"; "table2"))

Errors

To have more information about last operation if return value is False

$col:=$prepare.errors