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.What this means in practice is thatOracle Expert largely determines the relative importance of a given workload ele-Managing Workloads A-7 Overwriting Workload Datament by taking into account the relative importance of the element s parents inhigher categories of the workload hierarchy.The importance value for an element in one of the lower three categories does notentirely determine its relative importance.Instead, much of an element s relativeimportance is determined by the relative importance of its parents in the workloadhierarchy.Any of the Requests that are part of the most important Application in aworkload will have a higher relative importance than any of the Requests for lessimportant Applications.You need to know which SQL statements are part of which applications in yourworkload to get the best performance for your most important applications.What if you change the default behavior so that Oracle Expert gives more weight tothe importance value of an element when computing its relative importance?Oracle Expert follows the same basic principles in computing the relative impor-tance of elements.That is, the elements in the highest workload category (Applica-tions) are still considered to be the most important and elements in each of thelower categories are considered to be proportionately less important.Therefore,the relative importance of a given workload element is still largely determined bythe relative importance of the element s parents in higher categories of the work-load hierarchy.The difference is that when frequency is the dominant factor in determining rela-tive importance, Oracle Expert deems the Application with the highest frequencyvalue to be the most important element in your workload.Oracle Expert is alsolikely to give higher relative importance values to Requests that are part of thatApplication than to Requests that are part of Applications with lower frequencyvalues.To modify the importance value or frequency value for a workload element, selectthe element on the View/Edit page, choose Edit=>Modify, and enter a new valueon the Attributes page.Overwriting Workload DataThe Overwrite Existing option on the Workload Collect Options dialog box per-tains to workload data at the Application level.When you select Overwrite Exist-ing, Oracle Expert deletes all existing workload data and replaces it with theworkload data being imported for that Application.A-8 Oracle Expert User s Guide Appending to Workload DataAppending to Workload DataThe Append to Existing option on the Workload Collect Options dialog box per-tains to workload data at the Application level.When you select Append to Exist-ing, Oracle Expert saves the existing workload data for a particular Applicationand also saves the workload data being imported for that Application.OracleExpert assigns a new name to the newly imported workload data for the Applica-tion.Consider how this works in practice.The first time you import workload data col-lected by Oracle Trace, Oracle Expert stores that data as an Application namedServer Application.Then, if you later collect other workload data using OracleTrace and import it into Oracle Expert with the Append to Existing option enabled,Oracle Expert preserves the existing data for the application named Server Applica-tion and stores the data you are importing as an Application named Server Applica-tion 1.The next time you import workload data collected by Oracle Trace andenable the Append to Existing option, that workload data will be named ServerApplication 2, and so on.Managing Workloads A-9 Appending to Workload DataA-10 Oracle Expert User s Guide Glossaryaccess methodsOne of the categories of application tuning.During access methods tuning, OracleExpert determines what indexes are needed and generates the SQL statements tocreate, modify, and delete indexes as appropriate.Oracle Expert ensures that theindexing strategy is consistent with that of the Oracle cost-based optimizer.OracleExpert addresses sorted, hashed, and bit-mapped indexes.See also SQL tuning.advanced rulesRules that you would rarely want to view or edit, for example, low-level constantsthat are factored into the algorithms used by the Oracle Expert rules.See alsodefault rules and rules.analysisThe process by which Oracle Expert examines the tuning data collected for a data-base and generates tuning recommendations.Analysis reportA report that describes the Oracle Expert tuning recommendations.It provides adetailed explanation of the data Oracle Expert evaluated, how Oracle Expert inter-preted the data, and any risks associated with implementing the recommendations.ApplicationThe workload category at the top of the workload hierarchy.See also Business Unit,Transaction, and Request.Glossary-1 application tuning sessionA focused tuning session in which one or more application tuning categories(access methods or SQL tuning) are selected for one or more applications.See alsoaccess methods and SQL tuning.attributeA characteristic of a data object.You can view and edit attributes for objects usingthe Edit dialog box.base index tuningThe part of access method tuning where Oracle Expert scans schemas selected fortuning for evidence of implicit search operations, such as constraints or views
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