using SQLite in Django in production?

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Sorry for this question, I dont know if i've understood the concept, but SQLite is Serverless, this means the database in in a local machine, and it's stored in one file, this file is only accessible on one mode: if one client reads it, it's made only for reading mode for other clients, and if a client writes, then all clients have the write mode, so only in one mode at once! so imagine that i've made a django application, a blog for example; then how is this made using sqlite? since if a client enters to the blog he gots the reading mode to see the page and the blog entries, and if a registred client tries to add a comment then the file will be made as write mode, so how can sqlite handle this? so, does SQLite is here just like the BaseHTTPServer (the server shipped with django), for testing and learning purpose?

7 Answers

It is not impossible to use Django with Sqlite as database in production, primarily depending on your website/webapp traffic and how hard you hit your db (alongside what kind of operations you perform on it i.e. reads/writes/etc). In fact, approaching end of 2019, I have used it in several low volume applications with less than 5k daily interactions (these are more common than you might think).

Simply put for the current state of tech , at the moment Sqlite-3 supports unlimited concurrent reads (or as far as your machine / workers can handle), BUT only a single process can write to it at any point in time. Bear in mind, a well designed query/ops to the db will last only miliseconds!

Coming from experience in using sqlite as the only db for simple non-routine (by non-routine i mean that a typical user would not be using this app on a daily basis year-round) production web app for overseas job matching that deal with ~5000 registered students (stats show consistently less than 2k requests per day that involves hitting the database during peak season - 40% write 60% read), I've had no problems whatsoever with timeouts/performance issues.

It really boils down to being pragmatic about the development and the URS (client spec). If it becomes the next unicorn , one can always migrate the SQLITE to another RDBMS. For instance, see David d C e Freitas's take on migration in Quick easy way to migrate SQLite3 to MySQL?

Additionally the SQLITE website uses sqlite db at its backend .. see below...

The SQLite website (https://www.sqlite.org/) uses SQLite itself, of course, and as of this writing (2015) it handles about 400K to 500K HTTP requests per day, about 15-20% of which are dynamic pages touching the database. Dynamic content uses about 200 SQL statements per webpage. This setup runs on a single VM that shares a physical server with 23 others and yet still keeps the load average below 0.1 most of the time.

Bear in mind that the above quote is of course mainly referring to read operations, so the values may not be a applicable for write-heavy sites.

The example I gave above on the job matching application I built using sqlite as db is quite write heavy if you've noticed the numbers ... on average, 40% are short lived write operations (i.e. form submissions, etc etc) but bear in mind my volume hitting the db is only 2k per day during peak season.

Then again, if you realize that your sqlite.db is causing alot of timeout and bad user experience (408 !!! on form submission...), especially with Django throwing the OperationalError: database is locked error. (and then they have to key in the whole thing again)...You can always increase the timeout in your settings.py as per django docs as a temporary solution while you prepare for migrating the db.

'OPTIONS': {
# ...
'timeout': 20,
# ...
}

Again, it all boils down to pragmatic development and facing reality that the site may not attract as much activity as hoped , and is prone to over-engineering from the get-go.

There are many times that going for a simple solution enables faster time to market , essentially, to quickly test waters , and of course, be prepared If the piranhas do come in swarms and then its time to upgrade to another RDBMS.

With Django's ORM, for most cases you dont need to touch your models.py during migration to other supported sql db. Be VERY mindfull though that Sqlite does not support some more advanced functions or even fields that its bigger cousins MYSQL and POSTGRES do.

Late to the party, but the question is still relavant as of mid 2018.

"Client" of a blog site is a different term that a "database client". SQLite documentation refers to a client as a process opening a database file. Such process, say a django app, may handle many web app clients ("users") simultaneously and it still is going to be just one client from the standpoint of SQLiite.

The important consideration for choosing SQLite over proper RDBMS is whether your architecture is comprised of more than one software component connecting to a database. In such case, using SQLite may be a major performance bottleneck due to the fact that each app needs to access the same DB file, possibly over a network.

If multiple apps(database clients) is not the case, SQLite is a great production choice in 99% of cases. The remaining 1% is apps using specific DB features, apps under enormous load, etc.

Know your architecture.

The anwer to this question depends on the application that you want to deploy in production:

According to the how to use from the SQLite website, SQLite works great in production as the database engine for most website having low to medium traffic (which is to say, most websites).

They argue that the amount of web traffic that SQLite can handle depends on how heavily you use the database of your website. It is known that any site that gets fewer than 100K hits/day should work fine with SQLite. However, this 100K hits/day figure is a conservative estimate, not a hard upper bound.

In summary, SQLite might be a great choice for applications with fewer users and databases uses. Thus, use SQLite for website with fewer or medium interactions with the database and MySQL or PostgreSQL for website with higher interactions with the database.

Reference: sqlite.org

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