Should I use a Meta field or custom table?

Question

From a performance only perspective, can anyone with more more experience of the WordPress core tell me if writing something like a post view counter to a separate table in MySQL would be quicker for read and writes compared to using a Custom Meta Field?

I know most people will answer with Custom Meta Field solely on the reason that it's best to use the Wordpress API/functions. However my past 12 years has been building PHP applications that handle millions of users/high traffic and I know caching is the answer but I am interested in improving MySQL queries as well.

Looking at a lot of other plugins, I have seen it done both ways (for the record I am not asking this question for use in a plugin it will be for personal use in a theme)

Can anyone tell me any pros and cons of each method?

For example when a page is loaded in WordPress, I have not looked at how it is pulling in the meta fields, if it pulls them all in 1 query, it might be faster to use a meta field vs making another query to a separate table.

Answer 1

I can't really speak to the performance simply because I've not dug in to the internals. But from a pure logic approach the custom meta makes more sense to me.

The reason being that, at least from your description, you only really need a single field for each post/page. All you're doing is reading a value, incrementing it, and writing it.

Two lines of code using existing WordPress functions.