|
Luis Rodriguez wrote:
I was checking a SQL sentence with Visual Explain and the Index
Advisor suggested an index with two columns, the first one being
*SUBQJ0001 (The second column already exists as an index)
Does anyone have an idea what this refers to?
The *XXXYY#### field names are internal naming for the database
query engine, generally representative of an expression; i.e. any
specific column name does not describe the derivation. The prefix
SUBQ indicates the internal field is used to implement a subquery;
possibly the J indicates a join [implementation] column of the
subquery. The debug messages utilize similar naming prefixed with
an asterisk, to indicate that the /column/ included in the advised
or created-as temporary index was a derived expression; e.g. CPI432F
& CPI4321 as I recall, where the latter mentions specifically the
naming *MAP to indicate a derived field as result of an expression.
Regards, Chuck
--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.
As an Amazon Associate we earn from qualifying purchases.
This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].
Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.