Re: 5250 and un-do

On 12/21/2017 10:01 AM, Luis Rodriguez wrote:

Mmmm.. IIRC, in the latest DB2 versions (7.3 at least, don’t know if
available in 7.1/7.2 latest TRs) if you define a TIMESTAMP column it will
include a sequence that ensures the no duplication of the data?

Not near an IBM I (or the manual) right now, but that should avoid the
requirement for nanoseconds precision.

Thanks for reminding me about this. The reference is
Database > Programming > SQL programming > Data manipulation language >
Retrieving data using the SELECT statement

https://www.ibm.com/support/knowledgecenter/ssw_ibm_i_73/sqlp/rbafydtts.htm

'When the CURRENT TIMESTAMP special register or a variable with the
TIMESTAMP data type is used with a precision greater than 6, the
timestamp value is a combination of the system clock and uniqueness
bits. The uniqueness bits are assigned in an ascending order. Therefore,
comparison operations for timestamps with any precision will represent
an accurate order of when the timestamps were assigned.'

I myself tend to think of GENERATE_UNIQUE for a guaranteed unique value,
and I think of TIMESTAMP for... well, time.