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PROBLEM:
I noticed a difference between Visual DataFlex 7 and Visual DataFlex 11.1.
My code contains the following structure:
Open <Table>
Clear <Table>
Move <SomeValue> To <Table>.<SomeColumn>
Find Eq <Table>.<SomeColumn>
Reread <Table>
Move (<Table>.<SomeOtherColumn> + 1) To <Table>.<SomeOtherColumn>
Saverecord <Table>
Unlock
When the record was not found in the above case under VDF7 the <SomeValue> was kept in <Table>.<SomeColumn> and the save made a new record with the <SomeValue> in the column <SomeColumn>. In VDF11.1 the value in <Table>.<SomeColumn> is cleared by the REREAD command.
EXPLANATION:
The change is intentional. At low level, the REREAD performs a FindByRowId. If the FindByRowID does not find a record, it clears the buffer.
The code structure shown above is wrong (and has always been wrong). You should not rely on odd behavior to create records.
NOTE: Without <Table> in REREAD <Table> the behavior is again different because REREAD without table arguments only refinds records in active buffers and this is not one of them.
The correct code should be:
Clear <Table>
Move <SomeValue> To <Table>.<SomeColumn>
Find Eq <Table>.<SomeColumn>
If (Found) Reread <Table>
Else Lock
Move (<Table>.<SomeOtherColumn> + 1) To <Table>.<SomeOtherColumn>
Saverecord <Table>
Unlock
Contributed By:
Vincent Oorsprong
Company: Data Access Worldwide
email: vincent.oorsprong@dataaccess.eu
Web Site: http://www.dataaccess.eu
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