Entering content frame

Procedure documentation Updating the Statistics Information Locate the document in the library structure

You can use the Database Manager GUI to update the SQL Optimizer Statistics.

Prerequisites

The database instance is in the ONLINE operational state.

Procedure

...

       1.      Select the required database instance in the list of database instances. Choose Instance ® Tuning ® Optimizer Statistics.

       2.      Create a list of the tables for which the statistics are to be updated:

¡        To select all the tables for which an update is necessary, apply the default value * under Search.

¡        To select certain tables for which an update is necessary, enter the corresponding search arguments under Search.

Search Argument

Description

Owner

Owner

Table Name

Table name

Column Name

Name of Column

¡        To select all tables for which an update of statistics is possible irrespective of whether or not they need to be updated, under Advanced choose the option Select from tables.

       3.      Choose Actions ® Search.

A list of the tables is displayed that matches your criteria under Search and Advanced. From the Update Statistics Date and Update Statistics Time columns, you can tell when the statistics for this table were last updated.

       4.      From the list of tables, choose the tables for which you want to update the statistics.

       5.      You have the following options for updating the statistics:

¡        Updating the statistics for all rows of the selected tables (system default)

¡        Updating the statistics for a sample

To define the sample, enter the corresponding parameter under Estimate.

Parameter

Description

Use estimate value

Defines whether a sample is to be used

Percent

Percentage of table rows to be checked

The reliability of the random sample depends on the size of the table and the physical position of the data. For large tables (more than 1 million entries), we recommend a sample size of 20%.

¡        If you want to update the column statistics in addition to the table statistics, choose the option Include update columns for marked tables under Advanced, double-click the desired table in the list and then choose the desired columns.

       6.      Choose Actions ® Execute.

 

Leaving content frame