union 语句， 急该如何处理

union 语句， 急
select day(ghrq),count(djh) as sl,max('初诊')as xm from gh_sfdj where ctbz='0' and cf='0' group by day(ghrq)
union select day(rq),count(id) as sl,max('咨询') as xm from t_czdhlyb where bz='0' group by day(rq)
union select day(rq),count(id) as sl,max('留诊')as xm from t_czdhlyb where bz='0' and sflz='0' group by day(rq)


这个语句中 我想加个 留诊数量合计/咨询数量合计的 列，如何加，谢谢，也就是加个比率列

[解决办法]

SQL code

select day(ghrq),count(djh) as sl,max('初诊')as xm from gh_sfdj where ctbz='0' and cf='0' group by day(ghrq) union select day(rq),count(id) as sl,max('咨询') as xm from t_czdhlyb where bz='0' group by day(rq) union select day(rq),count(id) as sl,max('留诊')as xm from t_czdhlyb where bz='0' and sflz='0' group by day(rq) union select day(rq),sum(case sflz='0' then 1 else 0 end)*100/count(id) as sl,max('比例')as xm from t_czdhlyb where bz='0' group by day(rq)
[解决办法]
SQL code
select day(ghrq),count(djh) as sl,max('初诊')as xm, 0 as colfrom gh_sfdj where ctbz='0' and cf='0' group by day(ghrq) union select day(rq),count(id) as sl,max('咨询') as xm ,count(1) * 100/(select count(id) from t_czdhlyb where rq = a.rq and bz='0' and sflz='0')from t_czdhlyb awhere bz='0' group by day(rq) union select day(rq),count(id) as sl,max('留诊')as xm ,count(1) * 100/(select count(id) from t_czdhlyb where rq = a.rq and bz='0' )from t_czdhlyb where bz='0' and sflz='0' group by day(rq)