ConstraintError: Key already exists in the object store

Question

I am working with React 16.3.2, Redux 4 and Dexie 2.0.3.

when I am going to store data second time it throws this error message.

Error: ConstraintError: Key already exists in the object store.

   return dispatch => {
        db.table
        .add(data)
        .then (function(id){
            console.log(id)
        })
        .catch (function (error) {
            console.log("Error: " + error);
        });
    }

My Db schema:

   const db = new Dexie('ReactReduxDexieJsCRUD');
  db.version(1).stores({table:'++id,name,age,bloodGroup,donateBefore,weight' });

The first time it stores date well but after it gives the error.

I didn't worked with Dexie, but similar problem on MySql can be solved with "ON DUPLICATE KEY UPDATE". If you want on second call to add new data as new record, you need to set table key to be autoincrement, or to specify new key manually as second parameter to `add` call. If you want to add data or update data if exist, try [http://dexie.org/docs/Table/Table.put()](put) instead of `add`. — stolex, May 17 '18 at 18:59
Lovely comment #Oblosys & #stolex but it creates another issue it doesn't change the ID and it works like #update in database — MD Ashik, May 17 '18 at 19:04
works as expected, but you dont want an update, so what do you actually want to happen when a duplicate key is used? — , May 17 '18 at 22:51
@smith I don't want to use the duplicate key. and why it gives me error duplicate key . i am submitted my from second time with new value so it should be store new data with new ID ? — MD Ashik, May 18 '18 at 09:05
2nd time, sublimating a a duplicate key, what do you want to happen? — , May 18 '18 at 09:14
2nd,3rd..... it will store data in indexDB local database. continuously data inserted in the database. — MD Ashik, May 18 '18 at 09:24
@smith please take a look my code [Github project link](https://github.com/ashikjs/React-Redux-Dexiejs-CRUD) — MD Ashik, May 18 '18 at 09:29

score 8 · Accepted Answer · answered May 18 '18 at 09:46

How does your schema look like? (the part db.version(x).stores({...}) ?

The most common is to have inbound primary key, example:

db.version(1).stores({
  table: 'id, idx1, idx2...'
});

Here id is the primary key.

db.table.add({id: 1, foo: 'bar'}) will add object with id 1.
db.table.add({id: 1, foo: 'bar2'}) 2nd time will fail because id 1 exists.
db.table.put({id: 1, foo: 'bar2'}) will update object with id 1.

So what do you really want to do? You say you want to add new object with new key. If so, I suppose the error is that you give the same key second time.

You can also let the id be generated by the db

db.version(2).stores({
  table: '++id, idx1, idx2...'
});

Then you don't need to supply id in calls to add():

db.table.add({foo: 'bar'}) will add object with id 1.
db.table.add({foo: 'barX'}) 2nd time will add new obj with id 2
...

Thanks, #David it's perfect answer what I needed. – MD Ashik May 18 '18 at 18:10 — MD Ashik, May 18 '18 at 18:10

ConstraintError: Key already exists in the object store

1 Answers1