Command Codes in IMS DB

What is command code in IMS DB? Its benefits?

Command codes in a SSA makes the call powerful since DL/I treats such SSA’S differently from those without the command codes while performing some special functions.

Command codes save programming and processing time.

Command codes are specified in an SSA following the segment name and an Asterisk ‘*’.

An Asterisk ‘*’ in the ninth position in a SSA indicates that one or more command codes follow the asterisk.

A Blank or Left Parenthesis marks the end of command codes.

ONE or MORE command codes can be used in any combination.

Ten command codes are available under IMS .

F – Locate First Occurrence

L – Locate Last Occurrence

D – Retrieve this segment data into the I-O Area (Path Call)

N – Do not replace this segment

C – Concatenated key in this SSA

Q – Enqueue this segment

U – Maintain current position at this level

V – Maintain current position at this and higher level

P – Establish Parentage at this level

– – Null command code

Proc Option in IMS DB

What is Processing Option? (Proc Option in IMSDB)

Example of PROCOPT

PCB TYPE=DB, DBDNAME=HOSPHIST, 
PROCOPT=A, KEYLEN= SENSEG NAME=HOSPITAL, 
PARENT=0 SENSEG NAME=WARD, 
PARENT=HOSPITAL SENSEG NAME=PATIENT, 
PARENT=WARD SENSEG NAME=PBILL, 
PARENT=PATIENT PSBGEN  LANG=COBOL,  PSBNAME=LOGICPSB END

Proc options are the ones whose main function is Data integrity in IMS DB database.

References

Click here for List of Available Proc Options in IMS DB.