EXPLAIN has output with MATCHCOLS = 0. What does it mean?

Answer Posted / s

Non-matching index scan

Is This Answer Correct ?    3 Yes 2 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What os does db2 run on?

575


File not opened because library is *PROD and debug is UPDPROD(*NO). ? what may be the reason? how to solve it..?

2385


Explain db2.

624


What is db2 instance?

594


What is runstats db2?

588






can any one provide me the link for the db2 v7 & db2 v8 manual for Z/os? i need to know about the syntax of REORG in both versions & need to know the difference as well

1810


How does db2 sample database connect?

576


SET is the ANSI standard for variable assignment, SELECT is not. SET can only assign one variable at a time, SELECT can make multiple assignments at once. If assigning from a query, SET can only assign a scalar value. If the query returns multiple values/rows then SET will raise an error. SELECT will assign one of the values to the variable and hide the fact that multiple values were returned (so you'd likely never know why something was going wrong elsewhere - have fun troubleshooting that one) When assigning from a query if there is no value returned then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from it's previous value) As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does give it a slight speed advantage over SET.

2155


What is the maximum size of varchar data type in db2?

647


Explain about rct in db2?

644


What is the physical storage length of the data types: date, time, timestamp in the db2 database?

656


Why do chiropractors use drop table?

666


What is meant by explain?

665


When reorg is used?

680


What is cascading rollback?

625