PawCom Application Note 106: Unique Journal Keys
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When Peachtree designed the file structure for the Journal file JrnlHdr.dat they
specified that certain fields in the records must be unique. If you attempt to
insert a new journal record with an existing value for any of these fields you
will get a Btrieve error 5: Duplicate Key Value.

Although it is possible to define a unique key value to be autogenerating in
Btrieve so that a value of 0 will automatically cause Btrieve to generate a
new value on an insert, none of the keys for the journal files have been defined
that way.  This means that you must generate the unique values yourself.

The unique JrnlHdr keys are:

JrnlHdr:  NRecord, (JournalID,Period,TrxNumberL,Subindex1,Subindex2), GUID

NRecord is a unique number for every JrnlHdr transaction independent of the
kind of journal entry.  Although there is no requirement for this number to
be sequential for each new journal transaction, Peachtree always seems to
generate new transactions that way.  Since transactions can be entered for
different kinds of journals in any order, the subsequent NRecord numbers for
a particular journal will not necessarily be in sequential order but will
have gaps where the intermediate NRecord numbers were used for other types
of journals. The various journal classes and the JrnlHdr class in PawCom
have a property MaxNRecord that returns the largest NRecord number currently
assigned.  YOu can use this value + 1 to specify the NRecord number for a
new transaction.

The set of fields (JournalID,Period,TrxNumberL,Subindex1,Subindex2) must
be unique, meaning that the set of five values must not duplicate the
values for an existing record.  However, Btrieve does not have any restrictions
beyond this about the actual values used for the individual fields.

JournalID is an integer code for the type of journal transaction:

	General = 0
	Cash Receipts = 1
	Cash Disbursements = 2
	Sales = 3
	Purchase = 4
	Payroll = 5
	Inventory Adjusment = 7
	Assembly Adjustment = 8
	Purchase Order = 10
	Sales Order = 11
	Quote = 12

Subindex1 and Subindex2 are normally 0, but may have a value of 1 or 2 for
special kinds of transactions described in Chapter 4 of the PawCom manual.

Period is an internal period number (see Application Note 101).  The function
mwPeriodForDate in the module Support functions of the PawCom Access
application will compute the correct period for you based on the date.

TrxNumberL is a running counter for a given journal and period.  Each of
the journal classes and the JrnlHdr class have a property MaxTrxNumberL that
will determine the maximum TrxNumber in use for the specified journal and
period.  You can use this value + 1 for the TrxNumberL value for the next
transaction for a specific journal.

GUID was added to the JrnlHdr records with Peachtree V10 (2003) but wasn't
made a unique key unti V11 (2004).  A GUID is a universally unique identifier
that Microsoft generates by some unknown algorithm.  The PawCom class
Peachw has a GUID property that will return a new GUID that you may use
for new V11 or later JrnlHdr records.

Up until recently the JrnlRow.dat records did not have any unique keys.
However, the combination of NRecord, LineNo and TrxType should always be
unique to keep Peachtree happy.  Starting with the 2004 Manufacturing and
Distribution versions and for all later versions of Peachtreee the field
UMGUID must be unique if it is specified.