Re: Diffing data

The reason we don’t do data diffing currently is because if you are trying to solve the problem in a general manner, you quickly run into many difficult problems (size of dataset, what really constitutes a “different” cell value? How should you handle data that is the same, but with different PKs?, How do you handle data that you expect to be different? etc.)

I have heard of people dong a text database dump, then just using a regular text diff tool between the files.  You may be able to use liquibase’s generateChangeLog to get the data out in a standardized and nicer-to-diff format.  Depending on how your data is changing, there may be a poor signal-to-noise ratio.

I haven’t worked with content management systems like drupal much, but I have recognized that tracking of data changes in them is a huge problem.  Does anyone else have any experience with them and have suggestions?  Anything liquibase can do for that niche in particular?  Even if we do not support data diffs in general, it may be worth creating a drupal diff extension project in the upcoming (next 2 weeks) liquibase plug-in site.

Nathan

Hello!

On Controlling Checks (since 1.8) (http://www.liquibase.org/manual/diff) it’s stated that not only can you diff the database structure, but also the

data itself. However, later in that section it’s stated that the diffTypes command is only available when using generateChangeLog, not when

using the diff or diffChangeLog commands.

Is there any way that you could get the data diffed as well (using diffChangeLog)?

Since we’re developing in Drupal, where unconscious database changes are a common phenomena, we would need a reliable database differentiating system.

If the diff cannot differentiate the data between the tables, I guess the only solution left is 1)  Up Front Design/Development, 2) doing all the base work in one database,

3) using database dumps ? Any ideas on this?

Regards,

Christo