docs: private Statement compileAlterTableDropTTL(Table t) {
          if (t.getTTL() == null) {
              throw Error.error(ErrorCode.X_42501);
          }
          if (!StringUtil.isEmpty(t.getTTL().migrationTarget)) {
              throw unexpectedToken("May not drop migration target");
          }
          Object[] args = new Object[] {
              t.getName(),
              Integer.valueOf(SchemaObject.CONSTRAINT), Boolean.valueOf(false),
              Boolean.valueOf(false)
          };
          return new StatementSchema(null, StatementTypes.DROP_TTL, args,
                                     null, t.getName());
      }