[cruppstahl]

Not necessarily. I ran sysbench with InnoDB and manually switched off transactions, and it was a lot slower. I don't know why - didn't look into it.

upscaledb does use transactions. I.e. if you insert a row with a primary and a secondary index then upscaledb inserts two key/value pairs in two databases. All these operations are wrapped in Transactions. They are just not yet supported on SQL level.

[morgo]

In InnoDB everything is a transaction. If you do not begin/commit then each statement will be its own transaction.

Batching a group of statements together in a small transaction is usually better because it reduces log flushing. ACID only needs to be guaranteed on commit. Similarly, applying transactions in parallel is faster because of group commit.