我最后一个select语句中的编码错误

Question

您好我正在尝试创建编码，这样我就可以为每个月的员工输出薪水。我收到错误1064，这是一个语法错误。但我找不到错误。请帮忙

select * from wantlist;

alter table wantlist
add months double,
add years year;

update wantlist
 set months = 1,
     years = "2017"
where wantlist.wantlistno = "WLN005";

update wantlist
set months = 1,
     years = "2017"
where wantlist.wantlistno = "WLN018";

update wantlist
set months = 1,
     years = "2017"
where wantlist.wantlistno = "WLN023";

update wantlist
set months = 1,
     years = "2017"
where wantlist.wantlistno = "WLN053";

update wantlist
set months = 1,
     years = "2017"
where wantlist.wantlistno = "WLN066";


select * from wantlist;
    select staffid, months, years  count(wantlist.staffid) * 100 + 1000 as "Salary"
    from wantlist
    where months = 1
    group by staffid, months, years;