Postgres语法内部连接更新和临时表

Question

我正在使用页面9.3，我想知道如何在一条语句中执行此操作，甚至可能没有临时表。这对我来说似乎有点混乱。

create temp table docUse (
docid int primary key, 
name text, cnt int, 
mindate timestamp, 
maxdate timestamp); 

insert into docuse (docid,cnt) 
    select documenttypeID, count(documenttypeID) from AllDocs group by documenttype; 

update docuse set name = DocName from documenttype where documenttypeid = docid; 

update docuse 
set mindate = _minDate, maxdate = _MaxDate from(
    Select min(Creation_Date) _mindate, max(Creation_Date) _MaxDate, docid did 
    from AllDocs inner join docuse on documenttypeid = docid group by docid 
) foo where did = docid; 

样本返回行看起来像

761,Invoice,598236,1/1/2000 12:00:00 am, 2/19/2016 3:15:54 pm 

Answer 1

尝试：

insert into docuse (docid,cnt, mindate, maxdate, name ) 
SELECT x.documenttypeID, x.cnt, x.mi, x.mx, 
     (SELECT DocName d from documenttype where d.documenttypeid = x.documenttypeID) 
FROM ( 
    select documenttypeID, 
      count(documenttypeID) as cnt, 
      min(Creation_Date) as mi, 
      max(Creation_Date) as mx 
    from AllDocs a 
    group by documenttype 
) x;