Attributes for a Derby connection can be set via semicolon-separated lists on the connection url as well as in a Properties object passed to the java.sql.DriverManager.getConnection() and java.sql.Driver.connect() methods. The JDBC spec does not indicate what should happen if an attribute is specified both on the connection url and in the Properties object. For some databases, like Derby, the attributes on the connection url trump the attributes in the Properties object. For other databases, like MySQL, the reverse is true.
Because the JDBC spec does not dictate standard behavior here, we should document what Derby does. This information would be useful in some or all of the following sections:
Setting attributes for the database connection URL
Attributes of the Derby database connection URL
Working with the database connection URL attributes
Specifying attributes in a properties object