Bringing It All Together with SQL Nexus - SQL Server 2012 Internals and Troubleshooting - page 338

The second half of the report, shown in Figure 12-15, provides a table and an aggregated summary
of all the data imported from the SQL Trace i les. The Interval Start column has a drill-through
option that displays the TOP N queries aggregated by CPU usage, duration, writes, and reads for
that time interval. If you use the Unique Batches or Unique Statements hyperlinks available at the
top of the ReadTrace_Main report, you can view a list of the top resource-consuming queries from
the entire duration of the data collection. If you do drill through into the details of each query, you
will i nd two options — namely, drilling down by batch and statement.
WARNING One common pitfall with RML Utilities is assuming that a batch
always has statements associated with it. It is true that a batch will have one or
more T-SQL statements; but if the statements do not have SP:StmtStarting and
SP:StmtCompleted , then the batch will not have an entry in the ReadTrace
.tblStatements table, which is where the Unique Statements report goes to
fetch data for rendering the report.
FIGURE 12-15
NOTE The duration time reported for data collected from SQL Server 2005
instances and later is always measured in microseconds, whereas the CPU time is
reported in milliseconds. Forgetting this information is likely to invoke the wrath
of the developer whose query you erroneously pinpointed as the culprit!
You also have the option to apply i lters to the reports by selecting the application name or
database ID or login name. This greatly helps you reduce the amount of noise that you need to sift
through, enabling you to zoom into the data relevant to your analysis. Additionally, you can use the
Parameters tab in the toolbar to change the start time and end time using the sliders available.
This also helps in zooming into and analyzing a problem time period rather than looking at the
entire duration of the data collection period.