Sybase 12.5.1, User Manual

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User’s Guide
121
A P P E N D I X B
Specifications for Defining
Recording Session Views
This appendix describes rules and considerations for designing recording
session views.
Definition of key and result
Data items are either keys or results.
• A key data item uniquely identifies the rows returned in a view. For
example, in a view that defines per-process data, the Process ID data
item identifies each process.
• A result data item identifies the information to be returned concerning
each key value.
By using a mix of keys and results to define recording session views, you
control the data that Historical Server returns.
You can combine key data items within a view to narrow the scope of the
returned data. With the inclusion of each successive key, envision adding
the word “per” to a view definition. For example, page I/Os “per” database
table “per” process. (Only certain key combinations are valid for each data
item. See Table B-2 on page 124.)
To return server-wide data, define a view with no keys. In a view with no
keys, the result always contains exactly one row. (Only certain data items
are valid at the server level. See Table B-2 on page 124.)
Table B-1 provides examples of views using different key combinations.
Topic Page
Definition of key and result 121
Designing recording session views 122
Table of valid key and result data item combinations 124
Table of valid statistic types for data items 147