If anyone wants to check out a half-done lang with lacking documentation, I'd be happy to read your feedback: https://lutra-lang.org
Experts including Codd recognized the problems with SQL since that language got traction. Some alternatives got proposed, perhaps most notably Tutorial D by Chris Date and Hugh Darwen. No SQL replacement goes anywhere because of the vast quantity of SQL code and supporting tools dating back decades. Chris Date wrote the textbook on databases, and at least one book going through the problems with SQL and various implementations of the relational model.
SQL perfectly illustrates what Strostrup meant by "There are only two kinds of languages: the ones people complain about and the ones nobody uses." In some sense I would welcome a better query language. On the other hand I attribute decades of job security and steady income to knowing SQL and dealing with its problems.