Update README.md

Author: lganzzzo

README.md

@@ -39,3 +39,10 @@ More about Oat++:
 - [Consul](https://github.com/oatpp/example-consul) - Example project of how-to use oatpp::consul::Client. Integration with Consul.
 - [Microservices](https://github.com/oatpp/example-microservices) - Example project on how to build microservices with Oat++, 
 and example on how to consolidate those microservices using [monolithization](https://oatpp.io/docs/monolithization/) technique.
+
+### Databases
+
+- [MongoDB](https://github.com/oatpp/example-mongodb) - Example project how to work with MongoDB using [oatpp-mongo](https://github.com/oatpp/oatpp-mongo) mondule.
+Project is a web-service with basic CRUD and Swagger-UI.
+- [PostgreSQL](https://github.com/oatpp/example-postgresql) - Example of a production grade entity service storing information in PostgreSQL. With Swagger-UI and configuration profiles.
+