Choosing Physical Tuning Options › Non-SQL Tuning Options › Index Tuning Options › Additional Sort Options for Indexes

Additional Sort Options for Indexes

Standard and natural collating sequence

You can specify either of two collating sequences for indexes:

• Standard collating sequence for indexes orders key fields based on their EBCDIC collating sequence without regard to data type.
• Natural collating sequence for indexes orders key fields based on their data type. This means that negative numeric values will collate lower than positive values.

Duplicates option

As with sorted relationships, you can order index entries with duplicate index key values as duplicates first, duplicates last, or in db-key sequence.

If there are many duplicates and the index is unlinked, order the duplicates by db-key. This will reduce CPU in locating a specific index entry.

Representing additional index sort options

Represent additional sort options for a relationship on the data structure diagram by specifying:

• NATURAL if the collating sequence is to be natural. Standard is the default.
• DF for duplicates first, DL for duplicates last, or DBKEY for duplicates by db-key.