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How the VSAM KSDS uses index to locate the records ???

 
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Thirumurgann

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PostPosted: Fri Jul 25, 2008 4:53 pm    Post subject: How the VSAM KSDS uses index to locate the records ???
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If your answer is primary key then tell me how it get mapped to index of the particular record. Much confused about index whether its a memory pointer??? please help me to understand this concept clear with some Examples....
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Robert Sample

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PostPosted: Fri Jul 25, 2008 5:01 pm    Post subject:
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There is an IBM Redbook entitled "VSAM Demystified", http://www.redbooks.ibm.com/abstracts/sg246105.html?Open which will provide you with 508 pages of information on how VSAM works, exactly.
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expat

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PostPosted: Fri Jul 25, 2008 5:03 pm    Post subject:
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A good intro to VSAM
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Thirumurgann

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PostPosted: Fri Jul 25, 2008 5:21 pm    Post subject: Thanks Robert for reffering such wonderful book
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dick scherrer

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PostPosted: Fri Jul 25, 2008 9:03 pm    Post subject:
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Hello,

A somewhat less technical way to think of this is to think of the index of a vsam file like the index of an IBM manual. The index of the manual is concise containing the "key"s and a reference to the page in the manual containing the information.

The index of a vsam file works in much the same way. VSAM locates the key value in the index and from there gets the reference pointer to the actual data.

The actual data is then read and returned to the program like when we go to the indexed page and read what is there.
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Thirumurgann

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PostPosted: Mon Jul 28, 2008 12:18 pm    Post subject: Clear explanation Thanks dick scherrer
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Thirumurgann

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PostPosted: Mon Aug 04, 2008 11:56 am    Post subject:
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Thanks dick scherrer
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dick scherrer

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PostPosted: Mon Aug 04, 2008 12:07 pm    Post subject: Reply to: How the VSAM KSDS uses index to locate the records
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You're welcome icon_smile.gif

d
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