You've got to do a couple things for this to work. First, whenever you
archive or delete a record, you need to move it to the end of the database
using DmMoveRecord(StationDB, recordNum, DmNumRecords(StationDB)). But
remember you only need to archive/delete records if you intend to have a
desktop conduit that syncs the data to the desktop -- otherwise just use
DmRemoveRecord() and don't worry about deleted records.
next, use the DmQueryNextInCategory() function to fetch all records - it
stops when it hits a deleted record.
The correct method to access all records and avoid deleted records is to
use:
UInt recordNum;
VoidHand recHandle;
recordNum = 0;
recHandle = DmQueryNextInCategory (StationDB, &recordNum,
dmAllCategories);
while (recHandle) {
// handle record
++recordNum; // get next record
recHandle = DmQueryNextInCategory (StationDB, &recordNum,
dmAllCategories);
}
==-
John Schettino author of
Palm OS Programming For Dummies, http://schettino.tripod.com
-----Original Message-----
Subject: how to iterate through all records
From: Michael McFarland
After reading through the archives, I'm really not clear on this. If I
want to write a function that checks every record in the database to see
(for instance) what the maximum value is for one of the fields, what's the
best method to cycle through all *non-deleted* records? Is it safe to use:
UInt recordCount = DmNumRecords(StationDB);
for (i=0; i<recordCount; i++) {
recHand = DmQuery(StationDB, i);
// handle record
}
Or will this give me records that shouldn't be accessed (ie, have been
deleted but not hot-synced)?
