I am looking at using acts_as_versioned to manage revisions of data in several tables in my application. However, the default behavior of acts_as_versioned appears to apply to individual rows within a table. The tables I want to version are complicated lookup tables and what I really want is to version the entire contents of each table as a single set. Adding a row, deleting a row, or updating one or more rows should update the version of all rows. Is there a way to use acts_as_versioned to accomplish this? Is there a different approach that anyone can recommend? The second part of this question stems from a bit of self-doubt as to whether I took a sensible approach with these tables. Essentially what I have is the following table (c1..c3 represent criteria, r represents result) for each set of criteria: r c1 c2 c3 ------------------ 1 1 1 1 1 1 1 0 0 1 0 1 1 1 0 0 0 0 1 1 0 0 1 0 0 0 0 1 0 0 0 0 This allows me to select a result as follows myresult = mylookup.find(:conditions => ["c1 = ?", "c2 = ?", "c3 = ?", a, b, c]).r In this example, r is true when c1 is true and c3 is false or when c1 is true and c2 and c3 are true. This example is extremely simplified in the hopes of conveying the concept. The actual criteria tables include 5 or 6 conditions, some boolean, some integer. The reason that I would like to version the contents of this table as a set (all move to the next revision when one changes) is that I plan to store the revision of the criteria used along with the thing being evaluated. This should allow me to determine why an evaluated item failed or passed the criteria even in the future when the criteria have changed (possibly changing the evaluation result) by simply requesting the criteria for the revision that was originally used to evaluate the item in question. I chose to put the criteria into tables instead of directly into models because I want to allow the system administrators to update the criteria in the future through the application. Any ideas on other approaches?
on 2006-05-03 19:05
on 2006-05-03 19:07
Reposting to see if anyone in the PST time zone has any suggestions. Thanks, Eden
on 2006-05-05 22:55
Hello? Bumping this one more time just in case someone has some free time to think this through on a Friday. Just to summarize, I am looking for a way to version all rows in a table as a set. Any changes to any row would up rev all rows. Accessing a row should happen in the context of the set version, not the row version. My current inclination is to keep the schema below (since I can't think of another one) and modify acts_as_versioned so that it is really acts_as_versioned_set. Any other suggestions? Thank you, Eden
on 2006-05-05 23:47
Let me see if I understand correctly. Every time any field in any row is changed, you need to store a copy of the whole table so that you can reference it later?
on 2006-05-06 00:06
On May 5, 2006, at 1:52 PM, Eden Brandeis wrote: > really acts_as_versioned_set. (Assuming you need locking on the set, not full versioning.) You're working with rulesets which aggregate rules, so lock the ruleset itself. Don't CRUD rules directly; operate on them via their ruleset. # Doesn't have a version column (and likely no separate pk if AR didn't need it.) class Rule < AR::Base; end # Has a version column. class Ruleset < AR::Base has_many :rules # Saving the ruleset bumps its version, so so save its rules in the same transaction. after_save :save_changed_rules end ruleset.rules << Rule.new(foo, bar) ruleset.save! Check out Eric Evan's _Domain Driven Design_ for an excellent discussion of locking on domain boundaries. Best, jeremy
on 2006-05-06 02:11
Charlie, Thank you for responding. Yes, I want at least a diff of the whole table each time anything changes. The table is essentially a complicated lookup table (lots of variables in, one answer out), so the number of total rows is limited (about 10 right now). The table is functioning as a set of criteria. I pass in a bunch of true/false values (plus one or two ints) and get a pass or fail type result out of the table. Each combination of inputs will only match one row in the table. Does that help? I can post the actual contents of one of these criteria tables (there are several) if you think it will clarify things. Thanks, Eden
on 2006-05-06 02:14
I think you hit the nail on the head Jeremy! I think all I would need to do is store the ruleset id in the item that is evaluated. Then I can always refer back to the ruleset that was used for the evaluation even if the rules are modified (each modification is actually a new ruleset). I will check out the reference. Thanks again, Eden