the Undo/Redo mechanism described is not really for transactions but rather a "Button" within an application. So that the user can undo/redo changes.
Only one transaction can be active at a time. So to the best of my knowledge there is no "transaction number" as there can be only 1. Now you may go ahead and implement "pseudo transactions" and implement your own transaction number. etc... HTH, Ken David Barrett <[EMAIL PROTECTED]> wrote: What's the best way to group undo log entries by transaction? Is there a function that returns the current transaction number? Or what's the best way to set a global variable that is inserted into the undo log by the trigger? As background, the wiki has a great page on undo/redo: http://www.sqlite.org/cvstrac/wiki?p=UndoRedo But unless I misunderstand, it seems that a single transaction will create multiple entries in the log. For example, a transaction containing both an insert and a delete will generate two entries in the undo log. Therefore, to undo that transaction, I need to atomically commit the "undo" of both the insert and delete in a single transaction. That's fine, but the log created by the example doesn't seem to indicate which group of undo rows correspond to a single transaction. Indeed, the word "transaction" doesn't even appear in the page. Now, digging through the archives I see reference to a "transaction number" here: http://www.mail-archive.com/sqlite-users@sqlite.org/msg23962.html Is there any explicit way to get the current transaction number? I was hoping to see some "transaction_number()" function here, but I don't: http://www.sqlite.org/lang_corefunc.html If such a function did exist, then I could just update the triggers to insert that along with the corresponding SQL. Lacking that, what's the best way to manually to set some kind of global variable at the start of each transaction? One way is to maintain a separate table with a single cell containing the latest transaction number (which I manually increment at the start of each transaction) and then just SELECT that in the trigger sub-query, but that seems yucky. Is there an easier way I'm missing? Thanks! -david _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
