GET.RECCOUNT [Revelation On-Line Wiki]

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====== GET.RECCOUNT=====

^Published By^Date^Version^Knowledge Level^Keywords^
|Revelation Technologies|14 NOV 1989|2.X|EXPERT|GET.RECCOUNT|

==== GET.RECCOUNT ====

GET.RECCOUNT is an external function that counts the number 
of records in an Advanced Revelation Linear Hash file.

<code>
rec_count = GET.RECCOUNT(filevar, valid, force_count)
</code>

==== Using GET.RECCOUNT ====

This information is available in the header (descriptive 
block) of all Advanced Revelation files; however a facility 
is provided to perform an explicit count of the records in 
the file.  This may be necessary for network files that are 
highly active.  For all other files, an accurate count can 
be determined from information in the header.

GET.RECCOUNT works only with Advanced Revelation Linear Hash 
files.

=== filevar ===

Use filevar to pass the file variable for the source file.

=== valid ===

Valid returns true if the file accessed is a Linear Hash 
file.  Otherwise, valid is false.

=== force_count ===

Use force_count to pass a true or false value.  If true, an 
explicit record count is performed.  This should be used 
only with highly active network files.

==== Values returned ====

GET.RECCOUNT returns the number of records in the file if it 
was able to access the file. Otherwise, zero (0) is 
returned.  A true or false value is returned in valid, 
indicating whether the file is a Linear Hash file.

==== Correct Use of GET.RECCOUNT ====

<code>
/* The following code performs a record count of the 
SAMPLE_CUSTOMERS file, both via the standard method of 
reading the file header, and also by the explicit method, 
where each record currently available is counted. */

DECLARE FUNCTION GET.RECCOUNT
DECLARE SUBROUTINE MSG, FSMSG

EQUATE true$ TO 1
EQUATE false$ TO 0

* Get record count from the file header

file = "SAMPLE_CUSTOMERS"
valid = false$

force.count = false$

OPEN file TO filevar ELSE FSMSG(); STOP

count = GET.RECCOUNT(filevar, valid, force_count)

IF valid ELSE MSG("record count failed","","",""); STOP

no_force = count

* Force an explicit record count

force_count = true$

count = GET.RECCOUNT(filevar, valid, force_count)

force_cnt = count

text     = no_force:" records were counted without forcing"
text<<-1>> = force_cnt:" records were counted when forcing"

MSG(text, "", "", "")
</code>