Derick Rethans (of MongoDB) has posted an update to his site sharing the details about an improvement that comes with MongoDB 3.4 and is supported by the PHP driver: natural language sorting.

Arranging English words in order is simple—most of the time. You simply arrange them in alphabetical order. Sorting a set of German words, or French words with all of their accents, or Chinese with their different characters is a lot harder than it looks.

[...] Years ago I wrote about collation and MongoDB. There is an old issue in MongoDB's JIRA tracker, SERVER-1920, to implement collation so that sorting and indexing could work depending on the different sorting orders as described for each language (locale). Support for these collations have finally landed in MongoDB 3.4 and in this article we are going to have a look at how they work.

He starts off by explaining a bit about how Unicode collation works and PHP's support through the intl extension in the Collator class. He provides a code example using the class, showing the difference in sorting them first as English words then as Norwegian words. He moves into the MongoDB world and shows how the queries using this new collation support would be structured before moving back to PHP and using the MongoDB client to make the same requests. He also includes examples showing how to set the default locale, the "strength" (for the level of comparison), sorting and some interesting quirks with certain locales.