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Chain works with partial keys.
Chain works on partial key and if found it returns the record.
Works great on partial keys in externally-described mode. Not so great in program-described mode.
I created a test program that attempted to retrieve a record from a 2-key file, opened as program-described, using only the leading key.
If I tried a chain on the leading key field itself, it wouldn't even compile, because the declared key length (the full composite key length, in order to allow for retrieval by the complete key) didn't match the length of the key I was passing to CHAIN.
And if I put the partial key into a data structure of the appropriate length, whether the rest of the structure was zeros or blanks, it failed to find the record that was known to exist in the file.
The only way I could get it to do a partial key CHAIN was to declare the key length as that of the partial key, and CHAIN on that field alone. Which would prevent CHAINing on the complete key.
Is there a trick I don't know about, short of having the file declared and opened twice, that would allow a file opened as program-described to be CHAINed successfully on either the leading key field or the full key?
--
JHHL
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