What is Alternate Index ? How is it different from regular
index ?
Answers were Sorted based on User's Feedback
Answer / vish
The answer provided by NK is absolutely correct but we
should be very careful whil choosing the alternate index as
it may not be Unique. e.g. in the example given by NK, the
Emp# will always be Unique within a company but many many
employees can have the same name. So if we declare Emp_name
as AIX (i.e. alternate Index) and then use it for fetching
data then we may end up in multiple rows and hence we may
need additonal logic to arrive at the desired unique record.
Your comments are Welcome!!
| Is This Answer Correct ? | 14 Yes | 0 No |
Answer / nk
The purpose of any index is to provide the most efficient
access to the records in a file. Say you have a file of
employee names and numbers. Usually the primary index will
be the employee number. If you request a record by
providing the empl#, the access will be very fast. If you
have to very often request a record by the empl name, you
may want to create a second (a/k/a alternate) index based
on the name. So when you provide a name, the access to the
correct record also will be very fast.
| Is This Answer Correct ? | 10 Yes | 2 No |
what is difference between the sysabend and userabend?
How can you add a particular field in copybook?
what do you mean by copybook? and what is the difference between the copybook which we are using in working storage and procedure division.
What is the difference between structured cobol programming and object alternativelyiented cobol programming?
. How do we cast a variable in COBOL
What is XDC ?
How do you do in-line PERFORM?
How can we find that module can be called – whether DYNAMICALLY or STATICALLY?
What is the difference between a DYNAMIC and STATIC call in COBOL?
how will u code parm parameter and where pls ?
what is amode(24), amode(31), rmode(24) and rmode(any)?
how to check whether the open command of a sequential file is successful? or not?