Previous Topic: Define a DB2 LUW Global VariableNext Topic: Define a DB2 LUW Index Extension


Define a DB2 LUW Index

A primary key (PK) and a foreign key (IF) index is automatically created for each table in your model, based on the primary key and foreign key columns. If you designate columns as an alternate key group (AK) or an inversion entry (IE), the equivalent unique (AK) and non-unique (IE) indexes are also generated.

Use the DB2 for LUW Table Index Editor to create alternate key (unique) and inversion entry (non-unique) indexes for tables in your model. After you create an index, you can use the Index editor to modify its properties, such as the index name, column members, physical properties, user-defined properties, and comments.

To define a DB2 LUW Index

  1. Right-click a table index in the Model Explorer and click Properties.

    The DB2 for LUW Table Index Editor opens.

  2. Select an index and work with the following options:

    Note: Click New New icon in property editors to create a new object on the toolbar to create a index. Use the Enter filter text text box to filter a large list of indexes to locate the one you want to work with.

    Show FK Indexes

    Specifies whether or not to display foreign key indexes in the Index list.

    Physical Name

    Specifies the name of the index.

    Schema

    Specifies the default schema for the index.

    Type

    Shows the key group type. This is a read-only field.

    Is Unique

    Specifies whether or not the columns defined in the index must be unique.

    Physical Only

    Specifies whether or not the index should be suppressed from a logical model and appear in a physical model only.

    Generate

    Specifies whether or not to generate DDL for this object during Forward Engineering.

    Generate As Constraint

    Specifies whether or not to generate a constraint based on the information in the selected index during Forward Engineering.

  3. On the Members tab, select the columns from the table that you want to include in the index. In the Include Column section, select any additional columns that you want to include in the index.

    You can sort the columns and open the DB2 for LUW Table Column Editor.

  4. Work with the following fields on the General tab:
    Constraint Name

    Specifies the constraint associated with the index.

    Clustered

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

    Tablespace

    Specifies the tablespace name in which to create the index.

    Percent Free

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

    Level 2 Percent Free

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

    Minimum Percent Used

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

    Allow Index 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.

    Page Split Type

    Specifies the index split behavior. Select from the drop-down list. The valid values are symmetric, high, and low.

    Collect Statistics Type

    Specifies that the index statistics have to be collected at the time of creating the index. Select from the drop-down list. The valid values are basic, detailed, and detailed by sampling.

    Is Compressed

    Specifies that the index will use index compression. Select from the drop-down list; valid values are True and False.

    Is Partitioned

    Specifies that a partitioned index should be created.

  5. Click the Extend Using tab and work with the following options:
    Index Extension

    Specifies the name of the index-extension used to manage this index.

    Expressions

    Specifies values for any required arguments for the index extension. Each expression must be a constant value with a data type that exactly matches the defined data type of the corresponding index extension parameters, including length or precision, and scale.

  6. Click the Permission tab and grant permissions to users or roles on the selected index.
  7. Click the Comment tab and enter any comments you want to associate with the index.
  8. Click the Where Used tab to view where an index is used in the model.
  9. Click the UDP tab to work with user-defined properties for the index.
  10. Click the Notes tab to view history information and view or edit user notes.
  11. Click Close.

    The changes are saved and the DB2 for LUW Table Index Editor closes.