Single Table Analysis 

Use

You find this screen in the DBACOCKPIT navigating to Space ® Single Table Analysis.

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.

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, etc.

●      Indexes

Displays all the indexes that exist in the database for a table.The top half shows traditional table indexes (whose names begin with <table>) and the bottom half shows the SQL Server automatically generated Column Statistics (whose names begin with “_WA”). Each of these lists allows certain actions, which are 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 then others. The density is lowest when all values occur the same number of times

 

●      DBCC checktable:

This subscreen displays a button when pressed checks the integrity of the data, index and image pages of the table. The results are shown in an area below the button.