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Advice: how to convert SQL data?

2 pointsby adatta02over 16 years ago
I need some advice/a clever idea. Basically, I have a legacy SQL database that I inherited from our client's old development shop and I need to move all the data over to our new database.<p>The two schemas are vastly different - the old one is a MYISAM based system with no FKs and is missing some serious integrity.<p>My question is - is there some easy way to massage the old data into our new schema?<p>What I've been working on now is basically to build PHP objects for their old data and then write something to generate SQL statements for our new schema. Since we are using Symfony for the new project, I might also try and hook into Symfony and let it figure out the SQL. This will probably work but its really slow and tedious.

4 comments

fizxover 16 years ago
Not nearly enough info for anyone to help you with, and not interesting enough for the crowd here to likely care about. You should probably seek paid help from someone with experience.
bayareaguyover 16 years ago
Since the schemas are vastly different there's probably no alternative to building a custom ETL process. If you already have a workable solution to convert the data then you should probably just get to work and do what you can to keep your unknowns to a minimum even if it is a slow and tedious process. But if you don't really know if what you're doing will work then be honest about that upfront - you'll need to factor in additional time to compensate for mistakes. Try doing your conversions in a series of small steps with the appropriate testing along the way.<p>I've seen projects that sound like yours go way over budget because of well-meaning attempts to use "silver bullet" tools (often championed by non-stakeholders) that either took too long to figure out how to use properly or didn't end up working as well as expected.
akronimover 16 years ago
how much data are you moving?
DanielBMarkhamover 16 years ago
This is hard work. There are no magic bullets.<p>Some kind of ETL is all you got. Look forward to lots of exceptions.