Question

What is the most efficient solution when you need to record some data on every page view in your application – should you write to a file or write to the database?

Or maybe neither – perhaps you should cache the data in memory or a file and only write it to the database (or file system if you use a memory cache) occasionally?

Answer 1

If it’s purely recording a small amount of data with no subsequent lookups, straight file I/O is almost guaranteed to be more efficient. You’re losing all the advantages of a DBMS though — indexing, transactional integrity (really, ACID in general), concurrent access, etc..

It almost sounds like you’re talking about what amounts to simple logging. If that’s the case, and you don’t need to do frequent complex queries on the resulting data, you’re probably better off with straight file I/O if performance is a serious issue. Be careful of concurrent-write issues, though.

If the properties of an RDBMS are desirable, you might think about using SQLite, which for simplistic loads will get you better performance than most RDBMSs with less overhead, at the cost of some of the benefits (highly concurrent access and availability over the network to other machines are a couple of the “biggies”). It still wouldn’t be as fast as straight file I/O in the general case, though.

Your later mention of it being for page view tracking causes me to ask: Are you incrementing a counter, rather than logging data about the page view? If so, I’d strongly suggest going with something like SQLite (doing something like UPDATE tbl SET counter = counter+1). You really don’t want to get into the timing issues involved in doing this by hand — if you don’t do it right, you’ll start losing counts on simultaneous access (A reads “100”, B reads “100”, A writes “101”, B writes “101”; B should have written 102, but has no way of knowing that).