The DBAL takes the responsibility for automatic quoting of identifiers but it doesn't work in many cases:

1. The list of keywords is never complete and up to date.
2. Apart from the keywords, the logic of detection whether the needed identifier needs to be quoted is platform-specific but there's no platform API for that.
3. It's impossible to quote a keyword or another identifier that needs quoting manually.
4. The DBAL-level Table class is responsible for object name "normalization" which will lead to bugs in edge cases (e.g. cannot represent columns Foo and foo on the same table). See Normalize identifiers before filtering; fix getPrimaryKeyColumns not returning uppercased primary key #4689.

The details are to follow.