Sybase 12.5.1, Руководство пользователя

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hs_create_playback_session
62
Historical Server
" D H : M : S "
where:
• S – is seconds.
• M – is minutes.
• H – is hours.
• D – is days.
All components are numeric and can be one or two digits. Some
examples are:
"30" (specifies sample intervals of 30 seconds)
"10:0" (specifies sample intervals of 10 minutes)
"8:30:0" (specifies sample intervals of 8 1/2 hours)
"5 0:0:0" (specifies sample intervals of 5 days)
The first sample interval starts at start_time, and every sample, except
possibly the last one, has the specified length.
This option allows you to specify some data item changes in the
playback view. Also, Historical Server makes appropriate adjustments
to the data values to accurately reflect the requested playback session
length and playback sample intervals.
Choose this option to summarize data into any desired granularity. This
type of summary can mediate deviations in activity and is useful for
observing trends over time.
The
actual
,
entire
, and user-defined interval options have the following
features in common:
• Data item changes in playback views – for all three options, the
playback view can use statistic types different from those in the
input view, and it can include some estimated and calculated data
items not in the input view. It cannot include snapshot data, such as
current SQL statement data. See Table C-2 on page 165 for a
definitive list of data items and statistic types that can be included
in playback views when these options are chosen.
• Data adjustments – for all three options, Historical Server performs
appropriate mathematical computations to compensate for
differences in:
• the input recording sessions sample intervals and the requested
playback sample intervals