This dialog is opened with 
Open database(s) toolbar action and using Open Database action on each side of the Home tab. Also, if we are opening any previously loaded DB using the Recent projects panel on the Home tab, and that DB was loaded previously without Save passwords - this dialog will be opened to enter the password again.
Use connection strings - use this option to open a database using connection strings. This can be convenient if you already have a connection string and this can be necessary if you can't connect specifying just server, user, password and database. Application uses
ODP.NET connection string format.
Here is an example of the valid connection string:
Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=MyHost)(PORT=MyPort)))(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=MyOracleSID)));User Id=myUsername;Password=myPassword;
Use the same server name, credentials, and schemas for both databases - use this option to compare DBs located on the same server. In this case only Database field will be active for the right side, all other options will be used from the left side.
Display passwords shows DB user password text.
Save passwords (to reopen from recent DB list without password request) as mentioned simplifies work with recent databases, however please note that encrypted passwords are saved on your computer in the application settings file.
DB server name and port dropdown is pre-populated with recent used values (same as in Recent databases panel on the Home tab). Database dropdown is populated with recent database names available for that server. You can choose these values from the dropdown or type manually.
Schemas, comma separated optional, recommended - allows to setup schema filter for loaded schema objects. If specified, this filter overwrites 'Exclude schemas' filter from Settings dialog and usually it is more efficient than default exclude filter.
Test connection actions: Test tries to connect to the specified databse and shows OK nearby if connection was successful. In case of connection error it shows the error text which can be copied using Copy.
