Sql 等级对联盟
嗨,我需要根据where子句中满足的条件对我的行进行排序。所以我写了这个查询Sql 等级对联盟,sql,rank,Sql,Rank,嗨,我需要根据where子句中满足的条件对我的行进行排序。所以我写了这个查询 select 1 as priority, usr_fname, usr_lname from core_users where usr_fname = 'John' and usr_lname = 'smith' and suburb = '0162' union select 2 as priority, usr_fname, usr_lname from core_users where usr_fname =
select 1 as priority, usr_fname, usr_lname from core_users where usr_fname = 'John' and usr_lname = 'smith' and suburb = '0162'
union
select 2 as priority, usr_fname, usr_lname from core_users where usr_fname = 'John' and usr_lname = 'smith' and usr_title = 'Mr'
union
select 3 as priority, usr_fname, usr_lname from core_users where usr_fname = 'John' and usr_lname = 'smith'
现在我的TL坚持我可以在这里使用sql rank()/row_number()。是否有人可以指导如何操作?如果使用
行编号()
,则可以获得3个以上的值:
select usr_fname, usr_lname,
row_number() over (case when suburb = '0162' then 1
when usr_title = 'Mr' then 2
else 3
end) as priority
from core_users
where usr_fname = 'John' and usr_lname = 'smith' ;
您可以使用densite\u rank()
而不是row\u number()
来获得同等的优先级。但是,如果数据中未显示所有三组,则数字将为“1”或“1”和“2”
但是,更简单的版本只使用了一个大小写
表达式,并执行您想要的操作:
select usr_fname, usr_lname,
(case when suburb = '0162' then 1
when usr_title = 'Mr' then 2
else 3
end) as priority
from core_users
where usr_fname = 'John' and usr_lname = 'smith' ;
您的版本多次返回同一行——对于匹配的每个优先级返回一次。每行只返回一次,我猜这是您的实际意图。请标记您的RDBMSCool。我使用的是更简单的版本:D