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How can I use $where in spring data MongoDB?

I am not able to use $where in SpringDataMongoDb.
Is there any way to achieve this in SpringBoot?
db.getCollection('my_collection').find({ $where : function(){
for (var key in this.action_status){
return this.action_status[key] == false;
}
}})
Thank You.

It can be implemented in two ways one is using MongoTemplate and criteria query in spring boot application
Query query = new Query();
query.addCriteria(Criteria.where("action_status").eq(false));
List<User> users = mongoTemplate.find(query,MyCollectionClassName.class);
Another way is using mongo repository
#Query("SELECT mc FROM my_collection mc WHERE mc.status = false")
MyCollectionClassName findMyCollectionClassNameByStatus(Integer status);
References :
https://www.baeldung.com/queries-in-spring-data-mongodb
https://www.baeldung.com/spring-data-jpa-query

1: You can create a repository that extends MongoRepository and have a JSON Query method as follows:
#Query("{'action_status':{$eq:?0}}")
public List<YourObj> findByActionStatus(boolean status);
2: You can use Query By Object Attribute in MongoRepository. Supposedly you have a field called "isActionStatus" in your object, just declare this method in your repository:
public List<YourObj> findByIsActionStatus(boolean actionStatus);
Spring Data will break the method name like "select * from ... where isActionStatus = actionStatus
If you need a more complex query you can find the supported keywords here: https://docs.spring.io/spring-data/mongodb/docs/1.2.0.RELEASE/reference/html/mongo.repositories.html

Can I derive ARRAY_CONTAINS from query method name in Spring Data Couchbase Repository?

I have a Couchbase-Document "Group" with a list of group-members-names. I want to query for all groups of one person. I managed to do it with N1QL ARRAY_CONTAINS - see in code example - but i hoped that i could generate the query from the method name as it is usual in Spring Data.
Any help is appreciated :)
I tried
public List<MyGroup> findAllByMembers(String member); and public List<MyGroup> findByMembers(String member); but they just return an empty list - i guess they try to match the whole "members" value and don't recognize it as a list -, no errors.
Code
My Document with a List field
#Data
#Document
public class MyGroup {
private String name;
private List<String> members = new ArrayList<>();
}
My Repository
#RepositoryDefinition(domainClass = MyGroup.class, idClass = String.class)
public interface MyGroupRepository extends CouchbaseRepository<MyGroup, String> {
//#Query("#{#n1ql.selectEntity} WHERE ARRAY_CONTAINS(members,$1) AND #{#n1ql.filter}")
public List<MyGroup> findAllByMembers(String member);
}
Expected
Given a "group1" with "member1" in members.
repository.findAllByMembers("member1"); should return ["group1"].

Couchbase is limited by the Spring Data specification. Unfortunately, we can't simply add new behaviors to it (if you switch to a relational database, it has to work with no breaking points). So, whenever you need to query something that has a N1QL specific function/keyword, you have to write a query via #Query

Spring Data JPA #Query with foreign key: Parameter not matched

I have a table "Signal" with id, volume and object_id columns.
Object_id is a foreign key. I need to retrieve each signal that has a particular object_id.
Im trying to use this Query
public interface SignalRepository extends JpaRepository<Signal, Integer> {
#Query("select s from Signal s where s.object = ?1")
Optional<List<Signal>> findSignalByObjectId(Integer objectId);
}
It doens't work. If I change "?1" to 1 it gets the hardcoded value. If I try to query the "volume", it works fine.
I get this error:
Blockquote
nested exception is java.lang.IllegalArgumentException: Parameter value [1] did not match expected type

I'd recommend you omit the query and let spring data generate one for you. So your case may be represented somehow like that (in case of proper relation mapping defined):
public interface SignalRepository extends JpaRepository<Signal, Integer> {
Optional<Signal> findByObject(YourObjectType object);
}
If you provide more info e.g. your entities - you can get more help.

You can use Spring data to generate the underlying query like this :
public interface SignalRepository extends JpaRepository<Signal, Integer> {
List<Signal> findSignalByObjectId(Integer objectId);
}
or you can write the query with this return type and parameter:
public interface SignalRepository extends JpaRepository<Signal, Integer> {
#Query("select s from Signal s where s.object = :id")
List<Signal> findSignalByObjectId(#Param("id") Integer objectId);
}

Spring Data JPA and Exists query

I'm using Spring Data JPA (with Hibernate as my JPA provider) and want to define an exists method with a HQL query attached:
public interface MyEntityRepository extends CrudRepository<MyEntity, String> {
#Query("select count(e) from MyEntity e where ...")
public boolean existsIfBlaBla(#Param("id") String id);
}
When I run this query, I get a java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Boolean.
How does the HQL query have to look like to make this work? I know I could simply return a Long value and afterwards check in my Java code if count > 0, but that workaround shouldn't be necessary, right?

Spring Data JPA 1.11 now supports the exists projection in repository query derivation.
See documentation here.
In your case the following will work:
public interface MyEntityRepository extends CrudRepository<MyEntity, String> {
boolean existsByFoo(String foo);
}

I think you can simply change the query to return boolean as
#Query("select count(e)>0 from MyEntity e where ...")
PS:
If you are checking exists based on Primary key value CrudRepository already have exists(id) method.

in my case it didn't work like following
#Query("select count(e)>0 from MyEntity e where ...")
You can return it as boolean value with following
#Query(value = "SELECT CASE WHEN count(pl)> 0 THEN true ELSE false END FROM PostboxLabel pl ...")

It's gotten a lot easier these days!
#Repository
public interface PageRepository extends JpaRepository<Page, UUID> {
Boolean existsByName(String name); //Checks if there are any records by name
Boolean existsBy(); // Checks if there are any records whatsoever
}

Since Spring data 1.12 you can use the query by Example functionnality by extending the QueryByExampleExecutor interface (The JpaRepositoryalready extends it).
Then you can use this query (among others) :
<S extends T> boolean exists(Example<S> example);
Consider an entity MyEntity which as a property name, you want to know if an entity with that name exists, ignoring case, then the call to this method can look like this :
//The ExampleMatcher is immutable and can be static I think
ExampleMatcher NAME_MATCHER = ExampleMatcher.matching()
.withMatcher("name", GenericPropertyMatchers.ignoreCase());
Example<MyEntity> example = Example.<MyEntity>of(new MyEntity("example name"), NAME_MATCHER);
boolean exists = myEntityRepository.exists(example);

Apart from the accepted answer, I'm suggesting another alternative.
Use QueryDSL, create a predicate and use the exists() method that accepts a predicate and returns Boolean.
One advantage with QueryDSL is you can use the predicate for complicated where clauses.

You can use Case expression for returning a boolean in your select query like below.
#Query("SELECT CASE WHEN count(e) > 0 THEN true ELSE false END FROM MyEntity e where e.my_column = ?1")

Spring data provides method for checking the existence of a row using field:
example: boolean existsByEmployeeIdAndEmployeeName(String employeeId, String employeeName);

You can use .exists (return boolean) in jpaRepository.
if(commercialRuleMsisdnRepo.exists(commercialRuleMsisdn.getRuleId())!=true){
jsRespon.setStatusDescription("SUCCESS ADD TO DB");
}else{
jsRespon.setStatusCode("ID already exists is database");
}

Selecting fields on Spring Data

I'm trying to find information about how to select only certain fields of an entity using Spring Data (I'm using JPA). I want to select only specific information of an entity, the repository interfaces gives you the ways to return the information of the WHOLE entity!. Some times I only need 2 or 3 fields of an entity and returning 20,30, ...100.. fields may be a little overkill.
This kind of functionality is something that I would do using Hibernate Criteria Projections, or even JPA "SELECT NEW ...." queries. Don't know if it is possible with Spring Data.
Thanks.

What you can do is return a List<Object[]> from repository. Then in your service class iterate over this list and manually create the object you need. Sample repository method
#Query("select el.moduleId, el.threadId from ExceptionLog el")
public List<Object[]> tempQuery();

I think you can also do it in this way
SomeDataPOJO{
required col1
required col2
}
and then write query like this
#Query("select new SomeDataPOJO from requiredTable where xyz="abc")
public List<SomeDataPoJO> tempQuery()

Its not plain Spring Data but did you consider using Springs JdbcTemplate? Its also in the Context if you use Spring Boots Autoconfiguration and has several handlers for transforming results of the Query.
For Example for the Query SELECT a, b FROM EMPLOYEE WHERE ID = ? you could use
String query = "SELECT a, b FROM EMPLOYEE WHERE ID = ?";
List<Pair<String,Integer>> employees = jdbcTemplate.queryForObject(
query, new Object[] { id }, new ExampleRowMapper());
Where the ExampleRowMapper transforms each row from the result into your given Return type (Pair<String, Integer> in this case) and could look like
public class ExampleRowMapper implements RowMapper<Pair<String, Integer>> {
#Override
public Pair<String, Integer> mapRow(ResultSet rs, int rowNum) throws SQLException {
return Pair.of(rs.getString(1), rs.getString(2));
}
}
Example adapted from https://www.baeldung.com/spring-jdbc-jdbctemplate where you find more information.
Of course its not as typesafe as a JPQL as the Query is "raw" or "native" SQL but at least the response is again typesafe and I like it more than to return Object[] or something.