JDBC URL

a JDBC URL has a variety of formats. They have three parts in common. 
* Protocl. It is the protocol JDBC. 
* The name of the product / vendor, such as MySQL, or Postgres. 
* Database-specific connection details, typically contains the location and the name of the database. A location can be localhost or an IP address / port or a domain name. The location is optional. The database name is required.

Colons separate the three parts.
```
jdbc:postgres://localhost:5432/zoo
```