Dexie.exists()

Syntax

Dexie.exists(dbName)

Return Value

Promise<boolean>

Description

Checks whether a database with the given name exists or not. Returns a Promise that resolves with true or false.

IMPORTANT NOTICE

You normally won't need this method! Dexie will automatically detect if database creation or upgrade is needed. The following checks are made withing db.open():

• If database does not exists, Dexie will create it automatically.

• If database exists but on a previous version, Dexie will upgrade it for you.

• If database exists on the declared version, Dexie will just open it for you.

So, DON'T do stuff like:

Dexie.exists('my-database').then(function (exists) {
    if (!exists) {
        var db = new Dexie('my-database');
        db.version(1).stores(...);
        db.open();
    }
});

It's simply NOT needed. Instead, just do:

var db = new Dexie('my-database');
db.version(1).stores(...);
db.open().catch(function (err) {
    console.error (err.stack || err);
});

...and it will create the db when needed but just open it if not needing to create it.

Sample

As stated out in the 'IMPORTANT NOTICE' above, this method is never needed in normal scenarios. But if you of some reason just want to find out if a database exists without actually using it, you could do something like the following:

Dexie.exists("myDatabase").then(function(exists) {
    if (exists)
        console.log("Database exists");
    else
        console.log("Database doesn't exist");
}).catch(function (error) {
    console.error("Oops, an error occurred when trying to check database existence");
});