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The POSC specifications are Year 2000 (Y2K) conformant,
as defined in
DISC PD2000-1 A Definition of YEAR 2000 Conformity Requirements,
published by
British Standards Institution :
Year 2000 conformity shall mean that
neither performance nor functionality is affected
by dates prior to, during and after the year 2000.
In particular:
- Rule 1.
- No value for current date will cause
any interruption in operation.
- Rule 2.
- Date-based functionality must behave consistently
for dates prior to, during and after year 2000.
- Rule 3.
- In all interfaces and data storage,
the century in any date must be specified
either explicitly or by unambiguous algorithms
or inferencing rules.
- Rule 4.
- Year 2000 must be recognized as a leap year.
The following Y2K issues are noted:
- Rules 1 and 2.
- Not applicable,
since the POSC specifications do not include
software (see footnote 1).
- Rule 3.
- The Epicentre temporal data types are based on Entry Level SQL,
and are therefore understood to be Y2K compliant.
- The DAE C programming interface is Y2K compliant.
- The temporal datatypes of the DAE data access language
are based directly on Entry Level SQL,
and are therefore understood to be Y2K compliant.
- The mapping of temporal data types to
POSC Exchange Format (PEF) is Y2K compliant
(the temporal data types of
the underlying API RP66 data
format 2
are not used).
- The mapping of temporal data types into
the relational projection as published by POSC
is based on Entry Level SQL,
and is therefore understood to be Y2K compliant.
- Rule 4.
- The DATE and TIMESTAMP data type domain definitions
correctly recognize Year 2000 as a leap year.
- Unrestricted Year Range
- Rule 3 as stated does not rule out that a data type
is defined for a restricted range of years.
The POSC specifications are evaluated for compliance
with a more strict requirement:
that the century shall not be ambiguous, and
the year range shall not be restricted.
Footnotes:
- 1
In addition to specifications,
the POSC deliverables include software.
POSC does not develop or provide commercial software;
the software provided by POSC is intended as proof-of-concept only,
with no defined requirement for general robustness,
including any requirement for Y2K compliance.
No programming errors regarding Y2K issues are known
or have been reported.
- 2
The API RP66 DTIME (DATE/TIME) representation
is restricted to years between 1900 and 2155 inclusive.
Note that Rule 3 requires unambiguous representation,
but does not require unrestricted representation.
The temporal representations of
the POSC Exchange Format mapping
are both unambiguous and unrestricted.
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