5.6    Joining records

       BlueBook allows you to link records within a database via
       hypertext-like "joins" (up to eight per record).  This
       lets you impose a logical structure on your data, making
       it self-referencing, and thus rather more than a simple
       list.  A join also lets you jump instantly to a related
       record regardless of whether it is on the current List or
       not.

       You can join any two records, provided both have at least
       one free "slot".

       How?  Pick one and make it the current record (ie, bring
       it up on the Main screen).  Click the Join button on the
       Main screen (it will stay depressed, indicating that you
       are in joining mode).  Then get the other record onto the
       List if it isn't there already -- use Get or Search to
       bring it up if you have to.

       Now click the List button to display the List.  Find and
       highlight in white the other record.  Click the large
       Join button showing on the List screen.

       That's it.  Unless you have made an error, the two records
       are joined.

       An error?  Well, you can't join a record to itself, or the
       same two records twice, and you may find that the target
       record is already fully joined (no free slots).  In each
       case you are "beeped".

       When a join is successfully completed, the Main screen
       returns automatically, its Join button released.
       Otherwise the button stays depressed (with most functions
       disabled apart from Get, Search and List) until you click
       it again to release it, thereby switching out of join
       mode.

       Joins are displayed in a sub-panel on the Main screen,
       under the record itself.  They can be severed as easily as
       created.  Just highlight them in white -- click once,
       or Tab through the set -- and then click the Break button
       (or type B) twice, for confirmation.

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       If you need to see more than the Key line of the record to
       be joined (as displayed on the List), you can jump to it,
       see it in full, then return to the List display to do the
       actual joining (or continue looking).

       There's no button to do this jump: just type U (for jUmp),
       and click List/type L when you want to return from the
       Main screen to the List display.
       ----------------------------------------------------------

5.7    Jumping between records, and retracing your steps

       You "jump" between records on the List as outlined in
       section 5.3.  Jumping between JOINED records is done via
       the Joins panel, but otherwise it is the same.

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       BlueBook remembers your last 256 jumps, and can backtrack
       through them.  Just type Ctrl+U (^U) at the Main screen as
       often as you need to.
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