Purpose
The Master Index is the highest level of the B-Tree structure of the file system and contains a sorted list of all the CI descriptors. The MI command displays the following:
- The Master Index with the requested display option
- The checksum contained in the CID for each one that is displayed with the command
Syntax
The online help lists the display options (/P, /S, /M, /L, /H, /V, /X) as /dispopt.
- /P
- Positions to the MI. Nothing is displayed unless a problem exists.
- /S
- Shows the fixed area and a formatted display of the first and last CID of the MI segment.
- /M
- Same as /L.
- /L
- Shows the fixed area and a formatted display of all the CIDs in the MI segment.
- /H
- Displays a hex dump of the MI segment.
- /V
- Verifies that the MI segment has all CIDs in the correct order, that all sectors are accounted for, and matches the setting of the FIB.
- /X
- Same as /L.
Usage Notes
The prompt for the MI selector is shown below:
MI ==>
In addition to global and upper-level commands, the following lower-level commands are allowed at the MI prompt:
- DISPLAY (without an ordinalrange)
- DROP
- PATCH
- WRITE (if the database is not running on the AMP in the current scope)
No checksum exists for the MI itself, however, if checksums are enabled, CIDs with checksums will show additional checksum columns in the MI output screen.