Split value from one field to two

Question

I\'ve got a table field membername which contains both the last name and the first name of users. Is it possible to split those into 2 fields memberfirst<

Answer 1

If your plan is to do this as part of a query, please don't do that ^(a). Seriously, it's a performance killer. There may be situations where you don't care about performance (such as one-off migration jobs to split the fields allowing better performance in future) but, if you're doing this regularly for anything other than a mickey-mouse database, you're wasting resources.

If you ever find yourself having to process only part of a column in some way, your DB design is flawed. It may well work okay on a home address book or recipe application or any of myriad other small databases but it will not be scalable to "real" systems.

Store the components of the name in separate columns. It's almost invariably a lot faster to join columns together with a simple concatenation (when you need the full name) than it is to split them apart with a character search.

If, for some reason you cannot split the field, at least put in the extra columns and use an insert/update trigger to populate them. While not 3NF, this will guarantee that the data is still consistent and will massively speed up your queries. You could also ensure that the extra columns are lower-cased (and indexed if you're searching on them) at the same time so as to not have to fiddle around with case issues.

And, if you cannot even add the columns and triggers, be aware (and make your client aware, if it's for a client) that it is not scalable.

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^(a) Of course, if your intent is to use this query to fix the schema so that the names are placed into separate columns in the table rather than the query, I'd consider that to be a valid use. But I reiterate, doing it in the query is not really a good idea.