DB2 10.5 for Linux, UNIX, and Windows

Altering a histogram template

Use the ALTER HISTOGRAM TEMPLATE statement to alter an existing histogram template. Histogram templates are used by service subclasses and work actions to define the bin values for the statistics that are maintained using histograms.

Before you begin

You require WLMADM or DBADM authority to alter a histogram template.

See Workload management DDL statements for more information about prerequisites.

About this task

Some DB2® service subclass, work class activity, and request statistics are collected using histograms. All histograms have a set number of bins, and each bin represents a range in which activities or requests are counted. The type of units used for the bins depends on the type of histogram that you create. The histogram template describes the high value of the second-to-last bin in the histogram, which affects the values of all of the bins in the histogram. For more information on histograms, see Histograms in workload management.

Procedure

To alter a histogram template:

Issue the ALTER HISTOGRAM TEMPLATE statement, specifying the name of the histogram template that you want to alter and a value for the HIGH BIN VALUE parameter to alter the top value for the second-to-last bin.
Commit your changes. When you commit your changes the high bin value for the histogram is updated in the SYSCAT.HISTOGRAMTEMPLATEBINS view. The change does not take effect until the next time the workload management statistics are reset. See Resetting statistics on DB2 workload management objects for more information.
Optional: Run the WLM_COLLECT_STATS stored procedure to collect and reset the statistics so that the new histogram template is used immediately.