Indexed DB - compound index query where one or the other matches

Question

Apologies if my terminology is incorrect or this isn't well explained. I created something a while back with a websql database and would like to try changing it to an indexed DB.

I've created this index which allows me to find the objects where the hometeam is a certain value and the away team is a certain value:

objectStore.createIndex("homeAway", ["hometeam", "awayteam"], {unique: false});

So if I'm looking for a match between USA (hometeam) and Russia (awayteam) I'd get what I'm after:

var range = IDBKeyRange.only([hometeam, awayteam]);
var index = objectStore.index("homeAway");

But what if I wanted to use this .only method to find a match where a certain team is playing home OR away. Something like this:

var range = IDBKeyRange.only([hometeam || awayteam]);

Where if I entered Russia as both home and away it would find where they were either home or away. Is this possible?

Answer 1

Opening and index on two fields at once it's not possible however there is a indexed solution for your case.

You need to create a new index for an array field which will contain both teams with multiEntry property set to true.

objectStore.createIndex("teams", ["teams"], {unique: false, multiEntry: true});

And then store both teams as array of strings into that field

var obj = {
    hometeam: "Russia",
    awayteam: "Usa",
    teams: ["Russia", "Usa"]
}

Now when you query the database on that field you should get all games in which Russia is playing:

var index = objectStore.index("teams");
var keyRange = IDBKeyRange.only("Russia");
var cursorRequest = index.openCursor(keyRange);