Re: [Haskell-cafe] Inverse of HaskellDB

Have you given any thought as to how you want to approach versioning?

After giving this some more thought, I realized: 1) One of the "best practices" (even though I despise the term) of versioning schema is to include a script with the code which checks for each change to the tables, and makes the change if it is needed [1]. Each time you check out new code, you run the script to ensure that the code you are working with matches the tables you are working with. 2) A system that generates tables from Haskell types could also be made to check if a given table faithfully represents a given Haskell record type. It could then make any changes to the table so that it _does_ faithfully represent the record type. 3) In this way, your Haskell records ARE your table update script, just (like most Haskell code) incredibly terse. Your usual code repository will track when and by whom changes are made to the record. Of course, there are some issues with this, but I think it could be made to work well.

Hibernate does this, more or less, for Java classes. That might be a good place to look for ideas.

Good point. I'll start there. [1] http://www.codeproject.com/KB/database/DatabaseSchemaVersioning.aspx --Jonathan On Sat, Sep 25, 2010 at 3:45 PM, Rogan Creswick wrote:

On Sat, Sep 25, 2010 at 12:31 PM, Jonathan Geddes wrote:

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Does such a thing exist? If not, would you find it useful? I may take this up as a side project if it does not already exist and others would find it useful.

I've been looking for something along these lines too.

Hibernate does this, more or less, for Java classes.  That might be a good place to look for ideas.

--Rogan

...

Thanks,

--Jonathan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe