Index in data base table

Question

Hi all.
I need to create a Ztable ,it has 2 key fields and 2 index fields.
what is the use of index fields ? how is it diff from key fields?
how can i create index for my Ztable?
To be reward all helpfull answer.
JNJ

Answer 1

Hi,
Proceed as follows to create a secondary index on a table:
In the field maintenance screen for the table, choose Goto --> Indexes.
1. If you went to the field maintenance screen of the table in display mode, only correct the index (and not the table).
If indexes already exist on the table, a list of these indexes is displayed. Choose Create. A dialog box appears in which you must enter the three-place index identifier. If there are no indexes, go directly to the dialog box.
2. Enter the index identifier and choose Continue.
You will go to the maintenance screen for indexes.
3. Enter an explanatory short text in the field Short text.
4. Choose TabFields.
A list of all the fields of the table is displayed.
5.Select the fields which you want to copy to the index.
6.Choose Copy.
The selected fields are copied to the index.
7. If the values in the index fields already uniquely identify each record of the table, select Unique index.
A unique index is automatically created on the database during activation because a unique index also has a functional meaning (prevents double entries of the index fields).
8. If it is not a unique index, leave Non-unique index selected. In this case you can use the corresponding radio buttons to define whether the index should be created automatically on the database for all database systems, for selected database systems or for no database system.
9. If you chose For selected database systems, you must specify these systems.
You have two possibilities here:
List of inclusions: The index is only created automatically during activation for the database systems specified in the list. The index is not created on the database for the other database systems.
List of exclusions: The index is not created automatically on the database during activation for the specified database systems. The index is automatically created on the database for the other database systems.
Click on the arrow symbol behind the radio buttons. A dialog box appears in which you can define up to 4 database systems. Use the corresponding radio buttons to decide whether this list should be treated as a list of inclusions or exclusions.
Activate the index with Index ® Activate. The activation log tells you about the flow of the activation. Call it with Utilities ® Act.log. If an error occurred when activating the secondary index, you will automatically go to this log.
The secondary index is automatically created on the database during activation if the corresponding table has already been created there and index creation was not excluded for the database system.
If possible, check whether the database uses the index you created for selection. For more information see Checking whether an Index is Used.
Best Regards,
Rajesh.
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