hi there. i had similar thread some months ago http://groups.google.com/group/sqlalchemy/browse_thread/thread/1a3790d58e819f01/4d8e175fc04055aa the option 2 has 2 subcases. - one is to keep all numberings in one table and have a somewhat twisted query+update mechanism (Sequence if u have it, or manual +locks otherwise) - we had that before; - another one that i "invented" is to have a separate table for each kind of numbering, and each number is a reference to a record in that table. This needs no locking, querying and does not rely on Sequence or similar DB-query-and-update mechanims. it also can work on any scheme for numbering - the "number" itself can be anything, e.g. text, or list dept2-room3-pos7. but i guess can be somewhat too verbose.
On Thursday 09 October 2008 23:14:27 Lukasz Szybalski wrote: > Hello, > I was wondering if anybody has a good strategy for auto > incrementing fields. > > I want to auto increment field called "case#" . > > I have a choice of database auto increment on field "case#" or do > it myself? (correct? No other choices exists? or something in > between?) > > 1. I would like to be able to do pick a number where we will start > doing a case#? > 2. Reserver a case# for a special group which can auto increment > case# between 2,000,000-2,999,999, and add them as they come. > 3. I don't want to use (system_id) > > So it seems as the only way is to make my primary key: > case# - unique key, primary, not auto incrementing and let some > program manage auto incrementing. > > What options do I have with sqlalchemy to manage any range of these > primary keys? > 1. let db auto increment > 2. Hold the next case# in a separate database table, and let my > program use it to find next case# value. How would I lock/unlock > the next case# to make there is no race condition and each case# is > taken/successfully saved. > 3. Any other options? > > Have people exeperienced with other strategy that is > semi-automatic, and would for for these cases.? > > Thanks, > Lucas > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
