Row update with DB Row Lock (SELECT FOR UPDATE)

Problem

There’s an entire class of DB mutations that can be affected by race conditions. An example is incrementing a value by one.

So when updating a row, we need a way to acquire a DB row lock to prevent these types of race conditions.

Solution

I think this could be a good solution. If data is a function, then SELECT FOR UPDATE is used.

await prisma.counter.update({where: {id: 1}, data: counter => ({value: counter.value + 1})})

Alternatives

Or accept the above arguments with a new API like prisma.count.updateWithLock()

[Sytten]

I kind of disagree with this closing this, row locking is important and one step in providing more control to dev since long running transactions are out of the question for now. That could allow chaining of a findOne and update where the update takes some data from the findOne.

[schickling]

We’ve already drafted a Client API improved for this use case in this issue:

await prisma.users.findMany().update({ version: u => u.version.inc(5) })
await prisma.users.findMany().update({ version: u => u.version.dec(5) })
await prisma.users.findMany().update({ version: u => u.version.mul(5) })
await prisma.users.findMany().update({ version: u => u.version.div(5) })
await prisma.users.findMany().update({ version: u => u.version.mod(5) })
await prisma.users.findMany().update({ version: u => u.version.pow(5, 10) })
await prisma.users.findMany().update({ version: u => u.version.min(5, 10) })
await prisma.users.findMany().update({ version: u => u.version.max(5, 10) })

This won’t be implemented using a DB lock but by mapping to native atomic DB operations.