Directives

ADD INDEX

Add Key to Keyed File

Format

ADD INDEX keydescription$ TO filespec [,ERR=stmtref]

filespec	Can be a numeric expression indicating the open channel number to use or a string expression containing the pathname of the file to which the key will be added. If using the file channel, it must be to a keyed or memory file, and if it is a keyed file, the channel must be locked.
keydescription$	Description of the key using the same format as KEYED statement.
stmtref	Program line number or statement label to which to transfer control.
TO	Mandatory keyword, not case-sensitive.

(Support for using a file channel was added in PxPlus 2023 Update 1.)

The ADD INDEX directive allows keys to be added to a PxPlus Keyed file without having to rebuild the file. When adding keys to the file:

PxPlus builds keys on the fly.
Exclusive access to the file is required.
Keys are assigned the next available key number.
When adding a unique alternate key, the ADD generates an error, and the key is not defined if duplicate keys are in the desired index.
Only one key can be added at any one time (ADD or DROP cannot execute at the same time and will fail with an error zero).
The key names are case insensitive (key will be converted to uppercase characters).
The first character of the key name cannot be a "#" as this is reserved for access to the keys by key number.
If a key name is specified, it cannot be null; e.g. "".
Spaces are valid and significant. A name of " " (space) is valid and is not the same as a key of " " (space space).

add index ["KeyName":2:1:30]+[1:1:6] to "cstfile"