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Use

You find this screen in the DBA Cockpit by choosing Start of the navigation path Space Next navigation step  Single Table Analysis End of the navigation path.

The Single Table Analysis screen displays detailed information for a specified table. You can use this screen for advanced performance analysis of a table, its indexes, and settings.

You can perform some troubleshooting functions from this screen.

For a specific table, depending on your privileges, you can execute:

  • Update Usage - an advanced SQL Server command
  • sp_recompile - an advanced SQL Server command
  • Data Dictionary - see the properties of the table in the SAPData Dictionary
  • Table History - see the size history of the table
  • Index Analysis - view a combined screen that provides a view of Index Analysis, Current Indexes and Statistics, and Index Usage and Operational Statistics. The Index Analysis list suggests new indexes and the benefit from building them.

Features

For a detailed analysis, use the following tabs:

  • Overview

    Displays all detailed information about the size of a table, its allocated space and row information.In addition various properties of the table are shown such as the time of creation and whether page and row locking are disallowed, and so on.

  • Indexes

    Displays all the indexes that exist in the database for a table. The top half shows traditional table indexes (where the names begin with <table>) and the bottom half shows the SQL Server automatically generated Column Statistics (where the names begin with "_WA"). Each of these lists allows certain actions appropriate for the index or statistic.

    Some of these actions include:

    Button Description

    Statistics or Index Statistics

    Displays detailed information about the data distribution stored for the index or column statistic

    Distribution

    Displays the histogram, which is stored for the first column of the index or column statistic. Shows for each value in a histogram step how many rows are expected to fall within the step range. A percentage is also shown.

    Update Statistics

    Shows a screen with a button to update statistics with various options on one or all indexes

    Size and Fragmentation

    Displays fragmentation information for a selected index
  • Runtime Statistics

    Displays the operational and usage statistics of all indexes on the specified table.

  • Fields

    Displays the Fields of a table and the database specifics of each field.

    The following buttons are available to apply to fields when selected on this list:

    Button Description

    Selectivity

    Determines how many rows are typically identified by a key value. Selectivity helps, for example, to assess how efficient an index is when retrieving data associated with a key value

    Density

    This is also a measure of the selectivity of a column or combination of columns. But while selectivity simply counts the number of different values, density reflects whether some values occur more often than others. The density is lowest when all values occur the same number of times

  • DBCC checktable:

    This subscreen displays a button to check the integrity of the data, index, and image pages of the table. The results are shown in an area below the button. This screen is only displayed if the user has permissions to execute DBCC checktable on the database.

  • Statements:

    This subscreen is only available in SAP NetWeaver 7.0 EHP2 SP15 or higher. A button appears with the label Get Statements and also a text box to enter the number of desired rows. This retrieves by default the top 10 most expensive SQL Statements for the table. The list appears below if any statements are found, and two buttons SQL Statement and Explain allow the same statement analysis functions as described in the SQL Statement screen.