sql中查询中的when...then 语句

select cbid,  row_number() over(order by zxid) as xh ,xmid,zxid,bwid,bwcb,jbrid, replace(CONVERT(varchar(),jbrq, ),'/','-')as jbrq,
case cbzt when '' then '启用'
when '' then '未启用'    else '修改' end cbzt,shzt from jc_yscbfxb

select zxmid,row_number() over(order by xm.zzjgfhid,zxmmc) as xh,zxm.xmid,xmmc,zxmmc,htzj,zxm.fzrid,rs.ygmc,
case flag when '' then '启用' else '未启用' end flag,zxm.bz from jc_xmzxmb zxm left join v_jc_xmzzjg xm on zxm.xmid=xm.xmid left join rs_ygjbxxb rs on zxm.fzrid=rs.ygid