When building apps for users across different regions, a common challenge is handling multiregional data efficiently. For example, your app might need to connect to one database for North America and another for Europe.
How can a single app use the correct resources based on the user’s region? One approach is to combine dynamic queries with user attributes.
Here’s the approach:
1. Define and Set User Attributes
First, you need a way to capture region information for each user. This can be achieved by setting up user attributes - metadata attached to each user profile, such as a region attribute.
In my example, users either have "US" or "EU" set for their region attribute.
2. Get the Resource ID for Each Resource
You’ll need to grab the resource ID of each resource you want to use. You can find the resource ID within the URL on the resource’s configuration page.
If you're self-hosted, you can also find this by querying your Retool Postgres DB directly.
3. Dynamically Set the Query
Instead of writing static queries that point to a single resource, create dynamic queries that adjust based on the user’s attributes. When a user logs in, your app reads their region attribute and connects to the correct resource automatically.
You can do this by using a ternary expression that sets the resource ID based on current_user.metadata.region.
