make semi selection with thin join tables sample

[yaoguangluo]

setRoot:C:/DetaDB;
baseName:backend;
tableName:usr:select;
condition:or:u_id|<=|3:u_id|>|7;
condition:and:u_email|!equal|321:u_name|!equal|123;
getCulumns:u_id|as|detaId:u_email|as|detaEmail;
join:backend:usrToken;
condition:and:u_level|equal|low;
getCulumns:u_id|as|sId:u_level:u_password|as|SSID;
relation:and:detaId|==|sId;
aggregation:limit:0|~|1;

[yaoguangluo]

the query mostly like:

select u.u_id as detaId，u.u_email as detaEmail, t.u_id as sId，t.u_level，t.u_password as SSID
from usr as u
inner join {select t.u_id as sId，t.u_level，t.u_password as SSID
from usrToken as t
where t.u_level equal "low"
} on detaId == sId;
where (u.u_id <=3 || u.u_id>7 ) && (u.u_email !equal '321' && u.u_name !equal 123);
limit 0,1

tranditional SQL seems so complex...