I have a Table with a Map Field (2 bytes=16positions):= "Map" BYTE(8) DEFAULT X'0000000000000000' (this will hold 16 flags which can be viewed/set as either 1 or 0)

How do I test for position 15 X'nnnnnnnnnnnnnn1n' to see if it is = 1 in a SELECT statement ?

How do I UPDATE MyTable SET Map = X'nnnnnnnnnnnnnn1n' position 15 to 1 without affecting the others ?

Please advise - Thanks

Andrew,

BYTE(8) is 8 bytes = 64 bits, not 16.

Anyway, about your question:
It's possible, but not efficient. The only way I can think of to do this is to define a UDF implemented in an external module (dll) and use binary masks to test/set values.
Using only SQL I am not aware of any way to execute bit level operations (and it would defeat the basic principles of relational databases anyway).

--
Fernando Dias
[Team Elevate]

Yes but I was referring to 16 possible states of 1 or 0

Visually seeing the 16 flag states as well

Want 16 flags, trying BYTE for speed, could do STRING instead but prefer BYTES

Please show how to Read Bit from Byte, and then set Bit in Byte.