What collation does Evernote use for tags?

Question

Evernote's tags are case-insensitive, but I've not been able to find a specification for exactly what collation or culture is used for this.

The Tag specification (https://dev.evernote.com/doc/reference/Types.html#Struct_Tag) only states that "Case is preserved, but is ignored for comparisons."

Question: exactly what collation is being used?

Note: this is not a database question. This post has attracted answers that seem to automatically associate the term "collation" with databases. But this is an Evernote server-side data model question, and is best answered by Evernote experts or Evernote employees.

Answer 1

Evernote seems to be using a custom collation called "NOCASEUTF8"

Ex :- Find unused tags in database. Sort by tag name.

SELECT * FROM tag_attr
WHERE note_count IS Null
ORDER BY name COLLATE NOCASE

The "COLLATE NOCASE" is required to avoid a "no such collation sequence: NOCASEUTF8" error