Online Documentation for SQL Manager for DB2

Index Editor


The Index Editor dialog allows you to add/edit index properties.

 

To open the dialog, select the Database | New object... main menu item to open the New Object dialog, or open Table Editor, proceed to the indexes tab there and double-click an index to edit.

 

Index Editor

 

 

Use the Schema drop-down list to select the database schema for the index.

 

Use the Index Name edit box to set the index name. Note that the name of the index must be unique among all names of the index or index specifications described in the catalog.

 

Use the Table Name drop-down list to select the database table for which the index is created.

 

The Fields for index area allows you to select indexed fields.

To select a field, you need to move it from the Available fields list to the Selected fields list. Use the Move all to Selected Move to Selected Move to Available Move all to Available buttons or drag-and-drop operations to move the fields from one list to another.

 

Index properties

 

CheckBox Unique

This option determines uniqueness of the index, causes the system to check for duplicate values in the table when the index is created (if data already exist) and each time data is added.

 

CheckBox Collect statistics

Use this option to define if basic index statistics are to be collected during index creation.

 

CheckBox Detailed

Specifies that extended index statistics are also to be collected during index creation.

 

CheckBox Sampled

Specifies that sampling can be used when compiling extended index statistics.

 

CheckBox Cluster

Specifies that the index is the clustering index of the table.

 

CheckBox Allow reverse scan

Specifies that an index can support both forward and reverse scans; that is, scanning of the index in the order that was defined at index creation time, and scanning in the opposite order.

 

PCT Free

Specifies what percentage of each index page to leave as free space when building the index.

 

Min PCT used

Indicates whether index leaf pages are merged online, and the threshold for the minimum percentage of space used on an index leaf page.

 

Level 2 PCT

Specifies what percentage of each index level 2 page to leave as free space when building the index.

 

CheckBox Compress

The option specifies whether index compression is enabled.

 

Page split

Specifies an index split behavior:

SYMMETRIC

Specifies that pages are to be split roughly in the middle.

HIGH | LOW

Specifies an index page split behavior that uses the space on index pages efficiently when the values of the index keys being inserted follow a particular pattern. For a subset of index key values, the leftmost column or columns of the index must contain the same value, and the rightmost column or columns of the index must contain values that increase (if HIGH) or decrease (if LOW) with each insertion.

 

In tablespace

Specifies the table space in which the index is to be created.