The database holds more than numbers. It holds trust. Every breach of that trust costs more than money—it eats away at the core of the system. Micro-segmentation of sensitive columns is the hard line that keeps danger on one side and safety on the other.
Micro-segmentation breaks data access into precise zones. Instead of letting a user reach all customer data, you let them reach only what they need—column by column. Sensitive columns are the most critical. These are fields like personal identifiers, credit card numbers, medical details. They are the high-value targets. If you lock them down, you reduce the blast radius of any compromise.
The old model of role-based access control is too coarse. If a role grants access to a whole table, you expose everything in that table. Micro-segmentation applies fine-grained rules to individual columns. You define who gets which column, under what circumstances. You can enforce this at the database level, the application layer, or both. Combine it with strong encryption for sensitive columns, and you create layers an attacker must break through. Most never will.