Re: Table partitioning for cloud service?

[Israel Brewster <israel@xxxxxxxxxxxxxxxx>]

On May 21, 2020, at 12:12 PM, Sándor Daku <daku.sandor@xxxxxxxxx> wrote:

Hi,

On Thu, 21 May 2020 at 18:14, Christopher Browne <cbbrowne@xxxxxxxxx> wrote:

On Thu, 21 May 2020 at 11:53, Israel Brewster <israel@xxxxxxxxxxxxxxxx> wrote:

- Table-based tenancy (e.g. - each table has a "tenant_id" and queries need to specify the tenant)

The database/schema per tenant solution can be tedious when you want to modify something on the structure and you have numerous tenants.

Therefore I used the "tables with tenant_id" version in a similar situation but with a slight twist. One of the biggest issue of this solution is that if you forget to add the tenant_id to the where clause you are going to reveal one tenant's data to another.

I came up with the solution that the database user have no privileges for accessing the base tables. Instead of that I generate views for each tenant and they can access their own data in the underlying table through these views. Now if forget to address the right tenant in my client code(it still happens sometimes) and try to directly access the base tables I get a strongly worded reminder from the server.

Nice solution! I think I may go to something like that once I upgrade to a cloud solution that lets me add multiple users to the DB (the free tier of Heroku does not). In the meantime, while I just have the single customer, I can fake it easily enough.

Is there any shortcuts for referencing the proper views, or do you just append/prepend something to every table reference in your SQL? One nice thing about the database/schema approach is that I can just specify the search_path (or database) in the connection command, and then all the table references remain the same for all tenants. Also helps avoid the situation you mentioned where you forget to address the right tenant, since you only have to do it in one place. Of course, as you said, it can be tedious when you want to modify the structure. I’ll have to think about that a bit more.

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Israel Brewster

BrewsterSoft Development

http://www.brewstersoft.com

Home of EZPunch and Lyrics Presenter

Regards,

Sándor