Database Reference
In-Depth Information
Figure 11.4
Grouping and
Filtering a SUM
Function.
AND CY.COUNTRY_ID = S.COUNTRY_ID
GROUP BY CY.NAME);
There is a lot more to the OVER clause than the query in Figure 11.5.
Figure 11.6 shows the syntax for the OVER clause as demonstrated by the
previous example shown in Figure 11.5.
PARTITION BY
. This clause can be used to break the query into
groups.
ORDER BY
. This clause we have already seen.
Windowing Clause
. The windowing clause syntax allows placement
of a window or subset picture onto a set of data, applying analysis to
that data window subset only.
In fact, looking at the syntax diagram in Figure 11.6, the mind boggles
at what can be done with the OVER clause.
