Events in table maintains genrator

Question

hi gurus,
events in table maintains generator..... 
regards,
praveen

Answer 1

While creating the tables, sometimes we may need to update the table fields in the background
Lets take an example, if create a table with 10 fields in those 10 fields there are 2 fields which are User name and the Date, these 2 fields should update automatically when a record Inserted/Updated in the table.
For this, we need to create a table maintenance generator for that table. There in the table maintenance generator we have an option to create EVENTS.
In the table maintenance generator, Environment --> Modifications --> Events then a screen will be appear here,we need to create the Events, for updating the fields create 05(Creating a new entry) and 21(Fill hidden fields) .
In the EVENTS screen, press new Entries, there give 05 and give a name(This will become a PERFORM), then click the Editor pushbutton, this will be there at the right side of the entry, then a popup will be appear, you can create an include program, there inside of the include program write the below code
form CREATE_ENTRY.
TABLE-USERNAME = sy-uname.
TABLE-CHANGED_ON = sy-datum.
endform.
Then in the events screen enter 21 and give the form name as HIDDEN_FIELDS, then press the editor button, then in the editor
form HIDDEN_FIELDS.
TABLE-USERNAME = sy-uname.
TABLE-CHANGED_ON = sy-datum.
update TABLE.
endform.
This CREATE_ENTRY Perform will be triggered for every new entry and the HIDDEN_FIELDS fields will be triggered for every changed value in the table, so the Fields USERNAME and the CHANGED_ON fields will be updated automatically when a new record inserted into the table or an existed record changes through the table maintenance generator.
If you want any more functions, and then look at the events, you can press the F4 and look at the description of the event, then you come to know how to use and where to use.
Check these links
http://help.sap.com/saphelp_nw04s/helpdata/en/91/ca9f0ea9d111d1a5690000e82deaaa/content.htm
http://abapliveinfo.blogspot.com/2007/12/events-in-table-maintenance-in-sap.html
https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/8129f164-0a01-0010-2a8e-8765287250fc
Regards,