Tag Archives: Database

NativeScript-SQLite Multi-Threading!

The first release of NativeScript-SQLite was April 19th, 2015 on GitHub, and April 26th to NPM. I am happy to say this plugin is now almost 4 years old, and it was one of the first plugins available to NativeScript. I believe there was two or three others released before, like NativeScript-Flashlight. By June of 2015 we had a grand total of 18 (eighteen) plugins in the NativeScript eco-system, where today we are at almost 1,000 plugins.

NativeScript-Sqlite has had a lot of upgrades like encryption, prepared queries, and several bug fixes over the last 4 years. But the newest feature; I'm probably the most proud of. Without your app changing a thing (besides setting a simple option flag); NativeScript-Sqlite can now be fully multithreaded. What do I mean by that? In a nutshell all SQLite calls can now happen in a background thread. This means that if you are inserting or reading 20 records the UI won't freeze.

A couple years ago I did a session on Performance and NativeScript; my sample app showed how doing several different things could freeze the UI easily; and the best way to deal with this was to move as much of your work to background threads.

Now if you watch this image; every time I hit the SQLite button, the "n" freezes for a few seconds. This is because the work loading and processing the records is all done on the main thread which is the UI thread, causing the Animation to stop and/or stutter.

Since NativeScript-Sqlite has always been Promise (and/or Callback) based ASYNC code; it ended up that I could preserve the entire API as is; when allowing you to use multithreading. You just need to set a flag when opening up the connection and it will become multithreaded.

And this is what it looks like when sqlite is doing everything in a background thread. Notice how smooth it is. This is because the main thread is just waiting for the acknowledgement back that everything has been loaded.

If you check out the demo app; the code change is just this:

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Basically if the commercial plugin has been loaded; we flip on the multithreading flag. Otherwise we leave it off. (This way the app can test, Encryption, Multithreading, Commercial features, and no extra features all in the same codebase.)

The open source version of the plugin can be easily installed by typing tns plugin install nativescript-sqlite@latest, the open source repo can be seen at https://github.com/NathanaelA/nativescript-sqlite.

The commercial version which includes Encryption, transactions, prepared queries, and now multithreading can be purchased from my site at nativescript.tools.