mybatis高階查詢

sqlsession的獲取

sqlsessionfactorybean bean = new sqlsessionfactorybean();

bean.setdatasource(mysqldatasource());
bean.setconfiglocation(new pathmatchingresourcepatternresolver().getresource("classpath:mybatis/mybatis-config.xml"));
bean.settypealiasespackage("com.getword.entity");
sqlsessionfactory = bean.getobject();

假設user和role是一對一關係，中間表為sys_user_role

public class sysuser

select

u.id,
u.username username,
u.userpassword userpassword,
r.id "role.id",
r.rolename "role.rolename"
from sys_user u
inner join sys_user_role ur on u.id=ur.userid
inner join sys_role r on r.id = ur.roleid
where u.id = #

select

u.id,
u.username username,
u.userpassword userpassword,
r.id roleid,
r.rolename rolename
from sys_user u
inner join sys_user_role ur on u.id=ur.userid
inner join sys_role r on r.id = ur.roleid
where u.id = #

select

u.id,
u.username username,
u.userpassword userpassword,
r.id roleid,
r.rolename rolename
from sys_user u
inner join sys_user_role ur on u.id=ur.userid
inner join sys_role r on r.id = ur.roleid
where u.id = #

select

u.id,
u.username username,
u.userpassword userpassword,
r.id roleid,
r.rolename rolename
from sys_user u
inner join sys_user_role ur on u.id=ur.userid
inner join sys_role r on r.id = ur.roleid
where u.id = #

select

u.id,
u.username username,
u.userpassword userpassword,
r.id roleid
from sys_user u
inner join sys_user_role ur on u.id=ur.userid
inner join sys_role r on r.id = ur.roleid
where u.id = #

select

*from sys_user u
inner join sys_user_role ur on u.id=ur.userid
where u.id = #

select

u.id,
u.username username,
u.userpassword userpassword,
r.id roleid,
r.rolename rolename
from sys_user u
inner join sys_user_role ur on u.id=ur.userid
inner join sys_role r on r.id = ur.roleid
where u.id = #

對於id相同的user被歸為乙個user，相當於分組了

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