Building your app
Row-level security
Row-level security is a database rule that decides which rows each signed-in user can read or change, so one user cannot see another user's data.
Also called RLS, row level security
Looking this up for a class, a job, or something you want to build? If it is the last one, nommi reads your idea before you spend months on it.
A database keeps everyone's records in the same tables. Without a rule that limits each user to their own rows, an app can work perfectly in testing and still let one customer read another's information. Apps built quickly with AI tools often connect straight to the database, which makes this rule the line between private and exposed data.
When this shows up
Example, not a real founder: you build a journaling app and test it alone, so everything looks fine. Before inviting real users, you sign in as a second test account and find you can load the first account's entries. The missing piece is row-level security.
What to do next
Create two test accounts and try to open one account's data while signed in as the other. If you can, fix the rule before anyone else signs up.
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