Databases

The databases used in PowerLine all work on the same general principles described below:

Auto-refresh properties

Some of the values used to label a session are refreshed from the database whenever the session is opened. For example, if a rower called "Frederick" is attached as a crew member to a session, then if his name is later changed in the database to "Freddie", then the name "Freddie" will be displayed from then on.

Auto-refresh properties are indicated with a green arrow in the database dialog. Auto-refresh symbol

Other properties are copied into the session and are not subsequently refreshed. For example, the rower's squad.

So, as a rower goes through their career at a club, data might be accumulated where their squad changes. When search facilities become available in future versions, you might want to search for all sessions where name="Ann Bright" AND squad="junior", or all sessions where name="Ann Bright" AND squad="senior".

Uniqueness

Each entry is uniquely identified, even if the values are the same. Be careful: do not enter the same rower twice by mistake, as the software will be quite happy to accept two "John Smith"s.

Master / Slave

Each PC running the PowerLine software has its own database to provide crew, boats and venues. This means that the PC doesn't need to be connected to any other computers, such as a fileserver, in order to work. Each PC can be designated either as a "master" or a "slave" with regards to its own database.

  • if it's a "master" then the database can be changed.
  • if it's a "slave" then the database cannot be changed.

It is very important that within an organisation, only one of the PCs is designated as a "master" and all the others should be "slaves". For example, if an organisation has more than one PC as a master, then it becomes possible for several users to create database entries for the same rower.

So, decide which PC is going to be the master, and develop a strategy for periodically exporting / importing databases.

To determine the master/slave status of a PC, go to Tools→Options→Lists.

Note that if a PC is a "slave", it is still possible to enter names of rowers that aren't in the database. These will be displayed in italics, and can be updated later when the user has access to a database with that rower in.

Importing / Exporting

Any changes to the database on the master can be periodically transferred to the slaves by means of an export/import facility.

  1. go to Tools→Options→Lists.
  2. the import or export button will be available, depending on whether the PC is a slave or a master respectively

  3. Set PC as database master Set PC as database slave
  4. the software will ask for a file location for the import/export. By default, PowerLine database files have the extension .peach-lists

When importing a database, it is merged with the existing database - i.e. no entries are deleted. However, updated entries (for example, an updated rower's weight) will be refreshed.