comment on

I'm not sure what the problem you're trying to solve is. Let's assume your situation. The mistake is that the page is updating every field. Why isn't it just updating the fields that have changed? It's very simple Javascript to keep track of that, and JS is just the mechanism I've seen used where this was an issue. So, you have the following possibilities:

A updates the name and B updates the date. No collision.
A and B both update the name. The later one wins.

So, we've reduced collisions to those fields that are being changed together. The way I've seen this solved is to keep a history of all changes to all business-related fields. I'm not talking about an UPDATED_ON field for the table. I'm talking about a real history table, along the lines of:

ID
TABLE_CHANGED
COLUMN_CHANGED
ACTION
OLD_VALUE
NEW_VALUE
WHEN
BY_WHOM
[download]

Then, you have a history page, where you can see what changed, when, and by whom. This history table solves this problem, and a host of other problems, plus provides capabilities like rollbacks and the like. Now, I wouldn't suggest this solution for all situations, but it definitely seems warranted for things like user information. Remember, not everything should have a technology solution, especially when it's a human problem.

------
We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

... strings and arrays will suffice. As they are easily available as native data types in any sane language, ... - blokhead, speaking on evolutionary algorithms

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

In reply to Re: Concurrency control in web applications by dragonchild
in thread Concurrency control in web applications by cbraga

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