Feeling a little bit like you’re applying a motte and Bailey argument here.
The bold claim in the article was that there are many circumstances where adding an index isn’t necessary. Diverse examples were given. These included a MySQL database, where adding an index is no additional maintenance overhead whatsoever (FULLTEXT idx in the table DDL). The implication was that there are many circumstances that affect many people where even cheap and easy to implement indexes were not needed.
Now when challenged you’re retreating to the more defensible position that in the case where you’re querying an ad hoc data structure where you would have to implement your own index that that is often a bad trade off. Or maybe it was a bad tradeoff because this was a small app you were building that you knew you would be the long term maintainer for.
But that’s not what I’m talking about is it, and I don't know all the specific circumstances of your single specific project where this was the right choice, so we’re not going to get anywhere.
> These included a MySQL database, where adding an index is no additional maintenance overhead whatsoever (FULLTEXT idx in the table DDL)
MySQL didn't add support for FULLTEXT until v5.6, released 2013-02, a few years after I was working on this. At the time if I had wanted a full text search index it would have needed to be an additional service.
Looking now (no longer on my phone) it's a bit more complex than that: while MySQL has supported FULLTEXT indexes since 3.23.23 (2000-09-01) [1] if you wanted to use InnoDB (and you probably did -- it was much better than MyISAM [2]) you initially couldn't use FULLTEXT. That was added in v5.6 [3], and at the time I was developing this software the standard option was to set up Sphinx.
I've edited the post to add some of this history, so future readers understand this was about whether to add a dependency on an external indexing service.
The bold claim in the article was that there are many circumstances where adding an index isn’t necessary. Diverse examples were given. These included a MySQL database, where adding an index is no additional maintenance overhead whatsoever (FULLTEXT idx in the table DDL). The implication was that there are many circumstances that affect many people where even cheap and easy to implement indexes were not needed.
Now when challenged you’re retreating to the more defensible position that in the case where you’re querying an ad hoc data structure where you would have to implement your own index that that is often a bad trade off. Or maybe it was a bad tradeoff because this was a small app you were building that you knew you would be the long term maintainer for.
But that’s not what I’m talking about is it, and I don't know all the specific circumstances of your single specific project where this was the right choice, so we’re not going to get anywhere.