SQLite

I believe that the two queries listed below should yield a consistent result; however, he first fetches '0000', while the second fetches '0001':

SELECT HEX(MIN(a)) FROM (SELECT CHAR(0, 1) COLLATE NOCASE as a UNION SELECT CHAR(0, 0) as a); -- 0000
SELECT HEX(MIN(a)) FROM (SELECT CHAR(0, 0) COLLATE NOCASE as a UNION SELECT CHAR(0, 1) as a); -- 0001

This issue seems to only affect COLLATE NOCASE.

Simpler test case:

SELECT char(0,1)=char(0,2) COLLATE NOCASE;

The issue here is that the NOCASE collating function stops its comparison at the first zero character it sees. This fact has been clarified in the documentation. See documentation check-in https://www.sqlite.org/docsrc/info/e751b0c91a80dd31