How to add document with map data to firestore using flutter

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I want to have a document like below

enter image description here

But when i use the following code to add new document containing map it adds the data like the one shown in below picture

 Firestore.instance.collection('users').document(some_docID).updateData({
      'map1.key1': 'value1',
      'map1.key2': 'value2'
    });

Even if I use setData it still adds data as below, not as I wanted which is in the above picture.

enter image description here

Also one thing is that if the document is already present and it has at least one map field then if I use the above code it adds the data as map only. the problem is only when I want to create new document with map values. If anyone could suggest a solution would be great help.

google-cloud-firestore firebase dart flutter
2 Answers

There is are several differences between document.updateData and document.setData which need to be understood:

Firstly, you cannot create a document using updateData. The document must be created before calling updateData or the call will fail. This might have been the source of your problems.

Create a document with nested data

You must use document.setData. setData requires that you specify your data in "nested" format, where fields are not "flattened" or "dot-delimited".

So for your example:

 Firestore.instance.collection('users').document(some_docID).setData({
      'map1': {
        'key1': 'value1',
        'key2': 'value2',
      }});

Update a document with nested data

If you want to guarantee that a document was previously created, then you should use document.updateData (which as mentioned before, will fail if document was not previously created).

updateData requires that nested fields be specified in "dot-delimited" fashion.

So for your example:

updateData({
      'map1.key1': 'value1',
      'map1.key2': 'value2',
});

Accidentally overwriting fields with nested fields in updateData

If you pass data in nested format to updateData, it will assume that you wish to fully replace the value of a key with the subsequent data.

For example, if your document has data {'a': {'b': 2, 'c': 3}} and you run updateData({'a': {'b': 4}}) the document will not just replace a.b with 4, but will also delete the c field, since it was not included in the a value passed to updataData.

To only fields explicitly, use the dot-delimited format or setData(data, merge: true) (see below).

Updating data using setData

Note: You can also still use setData to update data on a document. Still, the format required is "nested" and not dot-delimited.

If you wish to only update certain fields of document explicitly, then pass merge: true to setData.

user_67415760

You have to add the data like this:

 Firestore.instance.collection('users').document(some_docID).updateData({
    "map1" : {
      "key1" : "value1",
      "key2" : "value2"
    }
    });

This will create a map in the database.

user_70154000
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