如何在没有任何共同点的mysql中合并四个表

Question

我有四个表，它们之间没有共同之处。我的四个表有几列：

yum install php-bcmath

sudo install php-bcmath

预期输出为

Table 1: EpId,Name,Position,Email,ManagerId,To/From
Table 2: Type
Table 3: LocId,LocName
Table 4: PreName

到目前为止的查询是：

EpId Name Position email managerId To/From Type LocId LocName PreName 

但是会引发错误： 所使用的SELECT语句具有不同数量的列

Answer 1

使用cross join，但是似乎您只想为彼此的表获取1，您使用limit

select distinct t1.EpId, t1.Position, t1.email, t1.managerId, t2.Type, t3.LocId , t3.LocName , t4.PreName from 
Employee t1
cross join (select Type as Type from EpType limit 1)t2
cross join (select LocId as LocId,LocName as LocName from Location limit 1) t3
cross join (select Name as PreName from Premise  limit 1) t4