>>I am trying to have new records AUTO NUMBER. My method
>>is to index on a unique number field and add one number and that is the new number for the next record.
>>Having problems like this...
>>the first user adds a record and the computer issues a number 3, at the same time the second user adds a record and the computer issues a number 4. Then first user decides to abort and the second user saves.
>>Now the second user has the number 4 for it's AUTO NUMBER and there is not a number 3 because the first
>>use did not save. How can I best do a AUTO NUMBER system?
>
>The common way to create unique record id (number) is following:
>1. System contains table 'Setup' with 2 fields: TableName C, Counter I.
>2. When user requests for new record id, he runs procedure to:
>- go to Setup and locate record by specific Tablename,
>- lock this record (RLOCK),
>- increment counter by 1,
>- use ne counter for INSERT command,
>- unlock Setup record.
Cant improve on that, however it sounds like you are worried about having gaps in the saquence of IDs..
If this is really going to be a problem, go ahead and append a new record when needed. If user 3 decides he doesnt want it, delete it. If you amend the "New ID" procedure so that it checks for a deleted record and recalls it before issuing a new ID, when user 5 comes along, they will get issued the previously created but unused "3".
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