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where to use index and where to use subscript?

 
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nagireddynarva

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Joined: 30 Apr 2005
Posts: 5
Location: hyderabad

PostPosted: Sat Apr 30, 2005 4:52 pm    Post subject: where to use index and where to use subscript?
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hi,
iam an entry level cobol professional.i want to know the at what instance should we use index and what instance should we use subscript? when index is more efficient than subscript what for subscript?

cheers..
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mmwife

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Joined: 30 May 2003
Posts: 1592

PostPosted: Sat Apr 30, 2005 9:58 pm    Post subject:
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Hi,

The conventional wisdom states that tables w/more than 70 entries should be referenced thru an index. That's the supposed "break even point" where the better speed of indexing exceeds the the additional overhead of its use.
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brain_s390

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Joined: 06 May 2005
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PostPosted: Sun May 15, 2005 12:27 am    Post subject: Re: where to use index and where to use subscript?
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Yes thats true !..Normally if the entries are large then its better if we use index.Let me know if you need more info on this.
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dbelton

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Joined: 10 Jun 2005
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PostPosted: Tue Jun 14, 2005 4:36 pm    Post subject: Re: where to use index and where to use subscript?
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brain_s390 wrote:
Yes thats true !..Normally if the entries are large then its better if we use index.Let me know if you need more info on this.


Also, if your table is loaded in sequence, and you need to do searches on it, then indexing it is faster since it can then do a binary search instead of scanning through the entire table until if finds the item you are looking for.
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