Performance of inserting data: SQL Azure vs Table Storage

Which is faster, SQL Azure or Table Storage? I thought it would be SQL, so I constructed a test to find out. I wrote a console application that inserted 1000 records into SQL Azure (1GB web edition), then the same number into Table Storage. The data was very simple (two small fields), the application used a single thread, and looped 1000 times running one insert statement at a time.

Everything was within the North Europe data centre, the test was run on a small compute instance.

The results:

SQL = 3 seconds

Table Storage = 207 seconds


The SQL insert was a raw SQL statement, whereas the Table Storage was using the SDK, and therefore using an object which had to be serialized. So, whilst it’s not a completely fair test, I don’t think the time was lost in serialization.

What this test doesn’t show is high parallelization. If you had many processes writing simultaneously to SQL Azure, you will eventually hit a bottleneck. With table storage this threshold is in theory much higher.

My code was very badly written. In real life you would parallelize, async and batch, but it shows that Table Storage, the very cheap, highly scalable storage resource can be a bit slow.