Databases Reference
In-Depth Information
Glossary Entries
include
See also:
Allen relationship
[
fills
1
].
“assert” cognates
Mechanics:
the cognate terms “accept”, “agree”, “assent”, “believe”, “claim”,
“know”, “say” and “think”.
Semantics:
terms which, for purposes of the discussions in this topic, may be
taken as synonymous with “assert” as that word is defined in this topic.
Comments:
There are important differences among these terms, in the fields of
epistemology and semantics. For example, some terms designate what
philosophers call “speech acts”, while others designate what philosophers
call “propositional attitudes”.
12/31/9999
Mechanics:
the latest date which can be represented by the SQL Server DBMS.
Semantics:
a value for an end date which means that the end of the time period it
delimits is unknown but assumed to be later than Now().
Comments:
For other DBMSs, the value used should similarly be the latest date which
can be represented by that DBMS.
Components:
end date, Now(), time period.
9999
Mechanics:
a DBMS-agnostic representation of the latest date which can be
represented by a specific DBMS.
Semantics:
a DBMS-agnostic representation of a value for an end date which
means that the end of the time period it delimits is unknown but assumed to
be later than Now().
Components:
end date, Now(), time period.
actionable
Description:
data which is good enough for its intended purposes.
Comments:
As a kind of shorthand, we say that the assertion time period of a row is
the period of time during which we assert that it is true. And if we
discover that a row is incorrect, and does not make a true statement, we
do end its assertion time period.
But some true statements are not actionable. For example, a currently
effective row in a 100-column table may have 10 of its columns filled with
accurate data, and the other 90 columns empty. So that row makes a true
statement “as far as it goes”, but because it is so incomplete, it is probably
not a statement that provides enough information to act on.
And some actionable statements are not even true. Financial forecasts,
for example, may be actionable. But because they are about the future,
what they describe hasn't happened yet, and so they are statements
which are neither true nor false.
1
Components:
currently asserted.
1
This, at least, is the standard interpretation of Aristotle's position on what are called
“future contingents”, as expressed in his work
De Interpretatione
.
