HQL查詢中取個別幾個字段

資料表：

要求:查詢type為4001，以content分組，本計算不重複的pcinfoid

mysql語句：

select

count(distinct pcinfoid) as
count,content,time from vrv_paw_reportlog where type=
'4001
'group
by content

對應的hql語句：

select  new map(count(distinct this.pcinfo.id) as

count,this.content as content,this.time as
time) 
from
com.vrv.paw.domain.reportlog this
where this.type=
4001
group
by this.content

注：使用關鍵字as

給「被選擇了的表示式」指派別名:

select max(bodyweight) as max, min(bodyweight) as min, count(*) as n

from cat cat

一起使用時最有用:

select new map( max(bodyweight) as max, min(bodyweight) as min, count(*) as n )

from cat cat

的物件，內容是別名與被選擇的值組成的名-值對映

這樣可以方便產生json字元

我犯的乙個錯誤：

TCP 幾個字段含義

1 tcp out of order tcp有問題 2 tcp segment of a reassembled pdu 3 tcp previous segment lost tcp先前的分片丟失 4 tcp acked lost segment tcp應答丟失 5 tcp window upda...

不同資料庫取前幾個欄位的方法

1.oracle select from table1 where rownum n 2.informix select first n from table1 3.db2 select row number over order by col1 desc as rownum where rownu...

Linq中查詢乙個表中指定的幾個字段

var ts t.findallitems where p p.companyid cursiteuser.companyid select s new distinct tolist orderbydescending s s.billperiod take 24 findallitems 為查詢...