I've ported some of my Entity from JPA to document and now porting some of my queries.
here is the JPA query:
em.createQuery("select distinct c from CustomerImpl c left join fetch c.addresses ca where (:name is null or c.firstName LIKE :name or c.lastName LIKE :name) and (:ref is null or c.externalReference LIKE :ref) and (:city is null or ca.city LIKE :city) order by c.firstName").setParameter("name", name).setParameter("ref", customerRef).setParameter("city", city).getResultList();
below is my attempt :
Criteria orNameCriteria = new Criteria().orOperator(Criteria.where("firstName").is(null), Criteria.where("firstName").is(name), Criteria.where("lastName").is(name));
Criteria orCustomerRefCriteria = new Criteria().orOperator(Criteria.where("externalReference").is(null), Criteria.where("externalReference").regex(customerRef,"i"));
Criteria orAddress = new Criteria().orOperator(Criteria.where("addresses.city").is(null), Criteria.where("addresses.city").regex(city, "i"));
Query nameq = new Query(new Criteria().andOperator(orNameCriteria,orCustomerRefCriteria,orAddress));
this query return zero size arraylist. I've then changed the orNameCriteria to use is clause and making sure the data contained in name variable has / as suffix and prefix. That didn't work as well.
but queries from mongoVue and RockMongo clients :
{ firstName: /SAM/}
returns data.
Question 1: How do you write LIKE CLAUSE with spring-data-mongo Criteria?
Question 2 : is that the right way to use or and and clause with criteria
Thanks for reading
Criteria.where("field").regex(pattern) should work
Since I don't have the ability add comments...
If you do a static import on Criteria, it will make your where clauses look a lot better.
Criteria orAddress = new Criteria().orOperator(where("addresses.city").is(null), where("addresses.city").regex(city, "i"));
Related
Assume I have the follow hasMany() models:
Country > State > City > Street > Person
And I want to retrieve person "John", but also know what country he belongs to:
$person = Person::with(['country'], ['state'], ['city'], ['street'],
['person'] = function ($query) {
$query->where('name', '=', 'John')
});
This generates a separate query for each model which does not seem efficient. Should I use join instead?
From my experience with MySQL 8+, there is not much difference, and I wouldn't use joins.
You can also use this package for nested relations
https://github.com/staudenmeir/eloquent-has-many-deep
Is there a way I can write a derived query in for a CRM Plugin?
Newbie on CRM dev here.
Query looks like this:
SELECT * FROM table1
WHERE table1.ID1 = XXXX AND table1.ID2 NOT IN (
SELECT table2.ID1
FROM table2
WHERE table2.ID2 = XXXX)
Writing the code using a queryexpression.
Unfortunately these kind of complex sql queries cannot be achieved via fetchxml or queryexpression queries. Especially like Subqueries, Not In scenarios.
Probably you need multiple resultset (EntityCollection), one for table1 & another one for table2, then transversing through it.
Another choice is LINQ queries, you can try.
On a side note, you can vote this idea to improve the querying ability.
If you truly are using CRM 2011, last time I checked, this is not possible, newer versions (2013+) you can perform this type of query.
Please see this article: https://msdn.microsoft.com/en-us/library/dn481591.aspx?f=255&MSPPError=-2147217396
var qe = new QueryExpression("table1");
var link = qe.AddLink("table2", "id2", "id1", JoinOperator.LeftOuter);
link.LinkCriteria.AddCondition("id2", ConditionOperator.Equal "XXXX")
link.EntityAlias = "notIn";
qe.Criteria = new FilterExpression();
qe.Criteria.AddCondition("id1", ConditionOperator.Equal, "XXXX");
qe.Criteria.AddCondition("notIn", "id1", ConditionOperator.Null);
You can use this expression with LINQ for CRM:
OrganizationServiceContext oservice = new OrganizationServiceContext(service);
using (oservice)
{
var query = (from table1 in oservice.CreateQuery("new_table1")
join table2 in oservice.CreateQuery("new_table2") on table1["new_table1id"]
equals table2["new_table2id"]
where
table1.GetAttributeValue<EntityReference>("new_id1")
== new Guid("the equal guid or field")
where
table2.GetAttributeValue<EntityReference>("new_id2").Id
!= table1.GetAttributeValue<EntityReference>("new_id1").Id
&& table2.GetAttributeValue<EntityReference>("new_id2").Id
== new Guid("the not equal guid or field")
select table1).ToList();
}
This is another way to QueryExpression. oservice.CreateQuery("new_table1") is the name of your entity in CRM
This works on CRM 2011 too.
Entity relation: Transaction(#ManyToOne - eager by default) -> Account
String sql = "SELECT new com.test.Pojo(t.account, SUM(t.value)) FROM Transaction t GROUP BY t.account";
List list = entityManager.createQuery(sql).getResultList();
By default JPA using Hibernate implementation will generate 1 + n queries. The n queries are for lazy loading of the account entities.
How can I make this query eager and load everything with a single query? The sql equivalent would be something like
SELECT account.*, SUM(t.value) FROM transactions JOIN accounts on transactions.account_id = accounts.id GROUP BY account.id
, a syntax that works well on PostgreSQL. From my findings Hibernate is generating a query that justifies the lazy loading.
SELECT account.id, SUM(t.value) FROM transactions JOIN accounts on transactions.account_id = accounts.id GROUP BY account.id
Try marking the #ManyToOne field as lazy:
#ManyToOne(fetch = FetchType.LAZY)
private Account account;
And change your query using a JOIN FETCH of the account field to generate only one query with all you need, like this:
String sql = "SELECT new com.test.Pojo(acc, SUM(t.value)) "
+ "FROM Transaction t JOIN FETCH t.account acc GROUP BY acc";
UPDATE:
Sorry, you're right, the fetch attribute of #ManyToOne is not required because in Hibernate that is the default value. The JOIN FETCH isn't working, it's causing a QueryException: "Query specified join fetching, but the owner of the fetched association was not present".
I have tried with some other approaches, the most simple one that avoids doing n + 1 queries is to remove the creation of the Pojo object from your query and process the result list, manually creating the objects:
String hql = "SELECT acc, SUM(t.value)"
+ " FROM " + Transaction.class.getName() + " t"
+ " JOIN t.account acc"
+ " GROUP BY acc";
Query query = getEntityManager().createQuery(hql);
List<Pojo> pojoList = new ArrayList<>();
List<Object[]> list = query.getResultList();
for (Object[] result : list)
pojoList.add(new Pojo((Account)result[0], (BigDecimal)result[1]));
Well PostgreSQL (And any other SQL database too) will block you from using mentioned query: you have to group by all columns of account table, not by id. That is why Hibernate generates the query, grouping by ID of the account - That is what is intended to be, and then fetching the other parts. Because it cannot predict in general way, what else will be needed to be joined and grouped(!!!), and in general this could produce situation, when multiple entities with the same ID are fetched (just create a proper query and take a look at execution plan, this will be especially significant when you have OneToMany fields in your Account entity, or any other ManyToOne part of the Account entity) that is why Hibernate behaves this way.
Also, having accounts with mentioned IDs in First level cache, will force Hibernate to pick them up from that. Or IF they are rarely modified entities, you can put them in Second level cache, and hibernate will not make query to database, but rather pick them from Second level cache.
If you need to get those from database in single hint, but not use all the goodness of Hibernate, just go to pure JPA Approach based on Native queries, like this:
#NamedNativeQuery(
name = "Pojo.groupedInfo",
query = "SELECT account.*, SUM(t.value) as sum FROM transactions JOIN accounts on transactions.account_id = accounts.id GROUP BY account.id, account.etc ...",
resultClass = Pojo.class,
resultSetMapping = "Pojo.groupedInfo")
#SqlResultSetMapping(
name = "Pojo.groupedInfo",
classes = {
#ConstructorResult(
targetClass = Pojo.class,
columns = {
#ColumnResult(name = "sum", type = BigDecimal.class),
/*
* Mappings for Account part of entity.
*/
}
)
}
)
public class Pojo implements Serializable {
private BigDecimal sum;
/* .... */
public Pojo(BigDecimal sum, ...) {}
/* .... */
}
For sure this will work for you well, unless you will use the Account, fetched by this query in other entities. This will make Hibernate "mad" - the "entity", but not fetched by Hibernate...
Interesting, the described behaviour is as if t instances are returned from the actual query and t.account association in the first argument of Pojo constructor is actually navigated on t instances when marshalling results of the query (when creating Pojo instances from the result rows of the query). I am not sure if this is a bug or intended feature for constructor expressions.
But the following form of the query should work (no t.account navigation in the constructor expression, and no join fetch without the owner of the fetched association because it does not make sense to eagerly initialize something that is not actually returned from the query):
SELECT new com.test.Pojo(acc, SUM(t.value))
FROM Transaction t JOIN t.account acc
GROUP BY acc
EDIT
Very good observation by Ilya Dyoshin about the group by clause; I completely oversaw it here. To stay in the HQL world, you could simply preload all accounts with transactions before executing the query with grouping:
SELECT acc FROM Account acc
WHERE acc.id in (SELECT t.account.id FROM Transaction t)
I have a method:
public List<Timetable> getTimetableTableForRegion(String id) {
List<Timetable> timetables;
TypedQuery<Timetable> query = em_read.createQuery("SELECT ..stuff.. where R.id = :id", Timetable.class).setParameter("id", Long.parseLong(id));
timetables = query.getResultList();
return timetables;
}
which returns this:
so, what am I missing in order to return a list of Timetable's?
ok, so, ..stuff.. part of my JPQL contained an inner join to other table. Even through in SELECT there were selected fields just from one table, which was used as type - Timetable, Eclipslink was unable to determine if this fields are part of that entity and instead of returning list of defined entity returned list of Object[].
So in conclusion: Use #OneToMany/#ManyToOne mappings (or flat table design) and query just for ONE table in your JPQL to be able to typize returned entities.
Not sure it might be something is looking for, but I had similar problem and converted Vector to ArrayList like this:
final ArrayList<YourClazz> results = new ArrayList<YourClazz>();;
for ( YourClazzkey : (Vector<YourClazz>) query.getResultList() )
{
results.add(key);
}
i have faced the same problem. and my entity has no one to one or one to many relationship. then also jpql was giving me queryresult as vector of objects. i changed my solution to query to criteria builder. and that worked for me.
code snippet is as below:
CriteriaBuilder builder = this.entityManager.getCriteriaBuilder();
CriteriaQuery<Timetable> criteria = builder.createQuery(Timetable.class);
Root<Enumeration> root = criteria.from(Timetable.class);
criteria.where(builder.equal(root.get("id"), id));
List<Timetable> topics = this.entityManager.createQuery(criteria) .getResultList();
return topics;
I want to select a list of file references from a table by looking at which users have the rights to retrieve that file. To do this I have 3 tables, a file table, an access control table, and a users table.
I am using JPA and Criteriabuilder (because there are more tables involved and I need dynamicle create the query, I am leaving out the other tables and predicates from this question for the sake of readability).
The following code works
CriteriaBuilder queryBuilder = em.getCriteriaBuilder();
CriteriaQuery<File> queryDefinition = queryBuilder.createQuery(File.class);
Root<File> FileRoot = queryDefinition.from(File.class);
List<Predicate> predicateList = new ArrayList<Predicate>();
Predicate userPredicate = FileRoot .join("FileAccesControlCollection").join("userId").get("usersId").in(loggedInUser.getUsersId());
predicateList.add(userPredicate );
queryDefinition.where(predicateArray).distinct(true);
Query q = em.createQuery(queryDefinition);
List<Files> results = (List<Files>) q.getResultList();
For the userpredicate I want to leave out the last join to the users table because the ID that I want to filter on is already present in the FileAccesControlCollection table, and a join is a computational expensive database operation.
What I tried is to do this:
Predicate userPredicate = FileRoot .join("FileAccesControlCollection").get("usersId").in(loggedInUser.getUsersId());
But I guess because the userId value in the FileAccesControlCollection entity class is a foreignkey reference to the Users class I get the following error:
Exception Description: Object comparisons can only use the equal() or notEqual() operators. Other comparisons must be done through query keys or direct attribute level comparisons.
Is there a way, using the loggedInUser entity or its Id, to filter the files by just joining the File class to the FileAccesControlCollection class and filtering on the userId foreign key? I am kind of new to JPA and using google lead me to a lot of pages but not a clear answer for something which seems to me should be possible.
So "userId" is mapped as a OneToOne? Then you could do,
get("userId").get("id").in(...)
You could also add a QueryKey in EclipseLink using a DescriptorCustomizer for the foreign key field and then use it in the query,
get("userFk").in(...)
try this:
Predicate userPredicate = FileRoot.join(FileAccesControlCollection.class).join(Users.class).get("{id field name in class Users}").in(loggedInUser.getUsersId());
good luck.