Consider them as Slick's internal identifiers for certain operations. Slick just happened to choose them identical to their most common SQL keyword equivalents so that the common driver just passes them through to SQL, but a particular driver can override `QueryBuilder.buildForm` and translate them to whatever is needed. But if you consider writing drivers as part of the public api, then of course the naming choice is not optimal because they use SQL naming instead of Scala naming. Probably we should adapt Scala naming for the identifiers in the long run.