How do you add join a table using Criteria class? - criteria

I am new to using Criteria, and i am trying to join tables on my query.
This is my expected query set up
Select * FROM ATable a INNER JOIN BTable b ON a.id = b.fk_id WHERE fk_pname = ":cat";
Do you know how i can add the "INNER JOIN BTable b ON a.id = b.fk_id"?
I already added in instance, but not sure how to add the other table.
Criteria criteria = this.getSession().createCriteria(ATable.class);
Thanks again for all your help

Something like this will do it -
Criteria criteria = this.getSession().createCriteria(ATable.class)
.createAlias("btable","b")
.add(Restrictions.eq("b.pname",":cat")
The string 'btable' refers to the property name in the ATable entity class that corresponds to the BTable entity.

Related

How to add complex inner query to #Query annotaion

normal sql query which work correctly in db in sql developer passing values for bID and period.
SELECT * FROM A WHERE abcID IN (SELECT abcID FROM B WHERE bID=1) AND period=3
in project at Repository class I passed as this
#Query("select a from A where a.abcID IN:(select b.abcId from B where bID=:RevID) and period=:period")
error comes as
Space is not allowed after parameter prefix ':' [select a from A
where a.abcID IN:(select b.abcId from B where bID=:RevID) and
period=:period]
I want to know how should I insert above query correctly in #Query annotation
First of all I would tell you below points.
you can't use select query as select a from A where a.abcID. Here a is a column so can't define something like a.abcID. It need to be select column from tableA a where a.abcID
Same for query use in IN clause. It needs to be like select b.abcId from tableB b where b.bID=:RevID
What you use as :RevID, :period need to be passed as #Param("RevID"), #Param("period") to the query method.
This is the query template.
#Query("select a.nameOfcolumnYouWantToRetrieve from tableA a where a.someColumn in(select b.someColumn from tableB b where b.columnValueOfTableBYouwantToMatch=:RevID) and a.period=:period")
Using this points, try below query.
#Query("select a.id from A a where a.abcID in(select b.abcId from B b where b.bID =:RevID) and a.period=:period")

Sql to LINQ query LINQ Query convert

I have a SQL query I want to write in LINQ
Here is my Query
SELECT DISTINCT *
FROM [IHQDB].[dbo].[Table1] as t1
inner join Table2 as t2 on t2.Table2 =t1.ChangedItemID
inner join Table3 as t3 on t3.Table3 = t1.FromUserID
where (t1.FromUserID=1 And t2.ContentItemID= t1.ChangedItemID)
OR (t2.LastModifiedBy=1 or t2.CreatedBy=1 )
Hi now its working fine but My query little bit different on place of 1 I need my userID on base of their First Name and Last Name from M_User table.
How can I get UserId on Base of First Name + Last Name.
Here is my LINQ CODE For Retrieving User Name
linq4 = from q in context.T_ContentItems
join p in context.M_Users on q.CreatedBy equals p.UserID
where (advanceKeyword.Contains(p.EmployeeFirstName + " " + p.EmployeeLastName)) select q;
advancechk12 = linq4.ToList();
========================================================================
What I require is that wherever I have written the value "1" (e.g. t2.CreatedBy=1), I need to find the UserID. For simplicity, I am able to get the names of all the filtered users in the advancechk12. How do I retrieve the UserID's of the list of usernames returned in advancechk12
You have to replace below mentioned Linq query with your models name.I just used the same name of the T-Sql.
var t1List = (from t1 in db.Table1
join t2 in db.Table2 on t1.ChangedItemID equals t2.Id
join t3 in db.Table3 on t3.Id equals t1.FromUserID
where ((t1.FromUserID=1 && t2.ContentItemID= t1.ChangedItemID) || (t2.LastModifiedBy=1 or t2.CreatedBy=1))
select t1).Distinct().ToList();

Get Greatest date across multiple columns with entity framework

I have three entities: Group, Activity, and Comment. Each entity is represented in the db as a table. A Group has many Activities, and an Activity has many comments. Each entity has a CreatedDate field. I need to query for all groups + the CreatedDate of the most recent entity created on that Group's object graph.
I've constructed a sql query that gives me what I need, but I'm not sure how to do this in entity framework. Specifically this line: (SELECT MAX(X)
FROM (VALUES (g.CreatedDate), (a.CreatedDate), (c.CreatedDate)) Thanks in advance for your help. Here's the full query:
WITH GroupWithLastActivityDate AS (
SELECT DISTINCT
g.Id
,g.GroupName
,g.GroupDescription
,g.CreatedDate
,g.ApartmentComplexId
,(SELECT MAX(X)
FROM (VALUES (g.CreatedDate), (a.CreatedDate), (c.CreatedDate)) AS AllDates(X)) AS LastActivityDate
FROM Groups g
LEFT OUTER JOIN Activities a
on g.Id = a.GroupId
LEFT OUTER JOIN Comments c
on a.Id = c.ActivityId
WHERE g.IsActive = 1
)
SELECT
GroupId = g.Id
,g.GroupName
,g.GroupDescription
,g.ApartmentComplexId
,NumberOfActivities = COUNT(DISTINCT a.Id)
,g.CreatedDate
,LastActivityDate = Max(g.LastActivityDate)
FROM GroupWithLastActivityDate g
INNER JOIN Activities a
on g.Id = a.GroupId
WHERE a.IsActive = 1
GROUP BY g.Id
,g.GroupName
,g.GroupDescription
,g.CreatedDate
,g.ApartmentComplexId
I should add that for now I've constructed a view with this query (plus some other stuff) which I'm querying with a SqlQuery.

Linq to SQL self join where right part of join is filtered

I am trying to map a self join where the right table must be filtered, e.g. SQL such as this:
select t2.* from table t
left join table t2
on t2.parentID = t.ID and t2.active=1;
I can figure out the syntax if I wanted to filter the left table:
// works
var query = from t in table
where t.active= 1
join t2 in table
on t.parentID equals t2.ID into joined
from r in joined.DefaultIfEmpty() ...
But I can't figure out how to filter the right table. It seems like it should be something like this...
// does not work
var query = from t in table
join t2 in table
where t.field = 1
on t.parentID equals t2.ID into joined
from r in joined.DefaultIfEmpty() ...
(not valid... join can't have where). There is discussion of using multiple from clauses, but if I create more than one from clause, so I can add a where to the 2nd one, I can't figure out how to join the results of them into a new temporary table.
I can't just add a "where" after the join; the right table must be filtered first or matches will occur, and a where clause at the end would remove the row from the left table that I do want in the output. That is, the output should have rows where there's nothing matched from filtered right table. So I need to filter the right table before the join.
I think you are looking to do this:
var query = from t in table
join t2 in
(from t3 in table
where t3.field = 1
select t3)
on t.parentID equals t2.ID into joined
from r in joined.DefaultIfEmpty() ...
Another way is to use multiple from like this:
var query = from t in table
from t2 in table.Where(x => x.field = 1)
.Where(x => x.ID == t.parentID)
.DefaultIfEmpty()
select ....

Entity SQL selecting from more then 3 tables

I am new to Entity framwork and currently trying hard to get used this programming paradigm. I have this query which i want to write in Entity SQL.
SELECT f.id, f.personName, c.Category, j.busCode, s.description, f.StartDate, (SELECT COUNT(*) FROM Analysis WHERE id = f.id) As numOfAnalysis
FROM forms f
INNER JOIN Jobs j ON f.id = j.id
INNER JOIN category c ON j.categoryid = c.categoryid
INNER JOIN stage s ON f.stageid = s.stageid
WHERE j.busCode NOT IN ('xyz', 'YYY')
ORDER BY startDate
I can get records from two tables but as soon as i add third table using the navigation property, i get error table category is not loaded in the current context. I am using .net 3.5. Keep in mind that EDM V2 doest not have foreign keys and i think the only way to traverse through the table relationship is navigation property.
Any help will be deeply appreciated.
Thanks
Coder74
If you use should be able to mount this Linq query.
I tried to put together, but in the rush and no such test is complicated.
You can use this reference as support: http://code.msdn.microsoft.com/101-LINQ-Samples-3fb9811b
var result = (from f in forms
join j in Jobs on f.id equals j.id
join c in Category on j.categoryid equals c.categoryid
join s in stage on f.stageid equals s.stageid
join a in Analysis on a.id equals f.id
where !(new int[] { 'xyz', 'YYY' }).Contains(j.busCode)
orderby f.StartDate
select {
id =f.id,
personName = f.personName,
Category = c.Category,
busCode = j.busCode,
description = s.description,
StartDate = f.StartDate,
numOfAnalysis = a.Count()
}).ToList()
Julio Spader
W&S Soluções de Internet