Hey Greg,
In the scenarios re: multiple DB to single with schema, it was mostly where one application was using one database for logs, one for main data, another one for something else, not really multi-tenanted. Also, it certainly isn’t a big issue, but in a lot of dev shops where multiple databases live, there is an assumption that you can do just the same in azure, and you sort of can but there are limitations. For example, if you have Db migration scripts (or system in place) that will ‘use [databasename]’, then this clearly wont work in azure. So then you have to have separate connections to each database (if you continue to use this convention), and manage it differently, so just a consideration. Also by saying ‘performance aside’, merely highlighting this multi-db vs single-db-multi-schema is something to think about, without introducing a lengthier performance talk. However, I would like to know more about the pitfalls (from a perf perspective) of multiple schemas. - Glav From: ozdotnet-boun...@ozdotnet.com [mailto:ozdotnet-boun...@ozdotnet.com] On Behalf Of Greg Low (??????) Sent: Wednesday, 1 February 2017 11:01 AM To: ozDotNet <ozdotnet@ozdotnet.com> Subject: RE: Used Azure SQL DB? Why or why not? Hi Glav, One caught my eye there. Can’t admit to like using schemas for tenants. I live in a world where “performance aside” isn’t an aside. That has way to much impact on query plans, caching, memory, etc. for my liking. Regards, Greg Dr Greg Low 1300SQLSQL (1300 775 775) office | +61 419201410 mobile│ +61 3 8676 4913 fax SQL Down Under | Web: <http://www.sqldownunder.com/> www.sqldownunder.com | <http://greglow.me/> http://greglow.me From: ozdotnet-boun...@ozdotnet.com <mailto:ozdotnet-boun...@ozdotnet.com> [mailto:ozdotnet-boun...@ozdotnet.com] On Behalf Of Paul Glavich Sent: Saturday, 28 January 2017 3:58 PM To: 'ozDotNet' <ozdotnet@ozdotnet.com <mailto:ozdotnet@ozdotnet.com> > Subject: RE: Used Azure SQL DB? Why or why not? Hey Greg, Use it all the time, and am working with a customer which is a greenfield project. Things to note: * Getting a good idea of performance related to what size/number of DTU’s. Initially, it is a pretty rough guess at best of times. Also, assuming all the queries written against it are good (which often is not the case) makes it harder to properly estimate. Over time and with adequate testing this issue becomes less though. * Retry with exponential fall off pattern. EF has a strategy to do this BUT doesn’t support transactions. Want to use a transaction? Then disable the retry/fall off policy and do your own. Can use something like Polly also to do this but it is an extra. * Syncing data between azure sql and an on premise sql. There are options but I think SQL Azure data sync is mostly it. If it doesn’t work well with that, well, make it up from there. * Customer initially started using a central SQL Dev DB. Caused all sorts of pain. I created a set of migration scripts so that Db can be run locally, with migration scripts for SQL in Azure. * Migrating thought process from multiple databases to a single Db with multiple schemas. Not that you can’t use multiple databases, but it is mostly easier (especially for migration scripts) to operate on one DB (performance aside). Probably a few others, but that is a brain dump for now. Also, I will be seeing you at ignite as I got asked to do a preso only recently. See you there :) - Glav From: ozdotnet-boun...@ozdotnet.com <mailto:ozdotnet-boun...@ozdotnet.com> [mailto:ozdotnet-boun...@ozdotnet.com] On Behalf Of Greg Low (??????) Sent: Saturday, 28 January 2017 1:20 PM To: ozDotNet <ozdotnet@ozdotnet.com <mailto:ozdotnet@ozdotnet.com> > Subject: Used Azure SQL DB? Why or why not? To my developer buddies: I'm preparing a session for Ignite where I'm discussing using Azure SQL DB for greenfield (new) applications. Would love to hear opinions on if you've used it, and what you found/learned, and if you haven't used it, what stopped you ? Regards, Greg Dr Greg Low 1300SQLSQL (1300 775 775) office | +61 419201410 mobile│ +61 3 8676 4913 fax SQL Down Under | Web: <http://www.sqldownunder.com/> www.sqldownunder.com | <http://greglow.me/> http://greglow.me
