Realm-js: Queries on list of strings property

[Sdoy]

Goals

filtered list of strings property

Code Sample

const BookrackSchema = {
    name: 'Bookrack',
    properties: {
        book_names:'string[]',
    }
};

Bookrack1.book_names=['A','B','C'];
Bookrack2.book_names=['B','C','D'];
Bookrack3.book_names=['C','D','E'];


a:realm.objects('Bookrack').filtered(`ANY book_names = $0 `,'B');
b:realm.objects('Bookrack').filtered(`book_names CONTAINS  $0 `,'B');

Expected Results

get Bookrack1 And Bookrack2

Actual Results

a.The keypath following 'ANY' or 'SOME' must contain a list
b.Object type 'Table' not supported

Steps to Reproduce

Version of Realm and Tooling

• Realm JS SDK Version: ?"realm": "^2.3.0"
• Node or React Native: ?node 8.4.0
• Client OS & Version: ?mac 10.13.4
• Which debugger for React Native: ?/None

[kneth]

It is currently not supported to query list of strings, only list of objects can be queried.

[umut885]

@kneth

It is currently not supported to query list of strings, only list of objects can be queried.

I think I have the same problem. Please, could you show me a workaround? Link to Stackoverflow

It is very important for me. I could donate a little money to you.

[nirinchev]

You can store the string values in a proxy object:

const StringValueSchema = {
    name: 'StringValue',
    properties: {
        value:'string',
    }
};

const BookrackSchema = {
    name: 'Bookrack',
    properties: {
        book_names:'StringValue[]',
    }
};

Then you can query like:

realm.objects('Bookrack').filtered(`ANY book_names.value = $0 `,'B');

[umut885]

@nirinchev
First, thank you so much for your response. I tried your example and i used the following for initializing:

       realm.write(() => {
          realm.create("Cars", {
            name: "Honda",
            category: "compact",
            image: global.base64_images.honda,
              specifications: ["test"],
          })

Now it returns me an error "Error: JS value must be of type "object", got (test).

for specifications i need a list of strings like: ["automatic,"suv","green"]. Excuse me.. do i miss something stupid?

[nirinchev]

That is correct - because we're faking a list of strings, you'll need to wrap them in objects:

realm.write(() => {
  realm.create("Cars", {
    name: "Honda",
    category: "compact",
    image: global.base64_images.honda,
    specifications: ["test"].map((str) => {
      return realm.create("StringValue", {
        value: str
      });
    }),
});

Similarly, if you want to get a list of strings from the collection, you'll need a reverse map:

const strings = car.specifications.map((s) => s.value);

[mingxin-yang]

@kneth I want ask that it is not supported to query list of strings, how about int or double? just strings?

[kneth]

@mingxin-yang Querying lists of primitive types (string, int, etc.) is still an open issue: https://github.com/realm/realm-object-store/issues/513

I hope that we can make some progress in the fall but I can't give you an ETA.

[hkwdaniel]

Hi I am also interested in the progress of this implementation

[vsalvans]

I think it's very necessary. At least, it should be explained that there is not support for query in list of primitive properties. I've already created a my db expecting that I could to such type of queries.
Also it would avoid to create a new class for each field when is as simple as a string or number.

Now I've got 2 options either change to a single string with a separator (no fun of this one) or create a class for each field (it adds more complexity to maintain the db)

[bmunkholm]

This is in progress now in realm-core.

[RealmBot]

➤ Brian Munkholm commented:

[~kenneth.geisshirt] I assume this is done now and can be closed?

[kneth]

Realm Core has implemented comparison operators for array of primitive types, and it has been released in Realm JavaScript v10.0.0-beta.1. I suggest that you try out the latest beta (v10.0.0-beta.7).