Kotlin find() using _id primary key with a string

Bob_Pappenhagen · September 18, 2020, 6:06pm

I’m sure its been asked before but I didn’t see it…

I have a string value for the _id I want to find

If I find() I get back {"_id": {"$oid": “5f64d2413ff0231ed8ef1b54”}, “Tag 0”: “I’m here”}
If I find using eq(“Tag 0” and “I’m here”) I get the jdoc

But I can’t figure out the syntax for using a string and _id

Help

MaBeuLux88 · September 19, 2020, 4:05pm

Hi @Bob_Pappenhagen and welcome in the MongoDB Community !

This is how I do it with Java. I guess it’s somewhat similar in Kotlin?

github.com

MaBeuLux88/java-spring-boot-mongodb-starter/blob/0e02444d44b1d0f62f85eab4a1e74a4097a0cbb8/src/main/java/com/mongodb/starter/repositories/MongoDBPersonRepository.java#L83


      
              return personCollection.find().into(new ArrayList<>());
          }
          
          
@Override
          public List<Person> findAll(List<String> ids) {
              return personCollection.find(in("_id", mapToObjectIds(ids))).into(new ArrayList<>());
          }
          
          
@Override
          public Person findOne(String id) {
              return personCollection.find(eq("_id", new ObjectId(id))).first();
          }
          
          
@Override
          public long count() {
              return personCollection.countDocuments();
          }
          
          
@Override
          public long delete(String id) {
              return personCollection.deleteOne(eq("_id", new ObjectId(id))).getDeletedCount();

Cheers,
Maxime.