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Initial,Next Extents and Byte allocation confusion

From: Poorna Prakash <poorna_prakash_at_sabre.com>
Date: 1998/02/06
Message-ID: <34DB898E.3EBE_at_sabre.com>#1/1 







Please clarify the confusion I have on extent allocation
and the bytes allocated. Upon inquiring the USER_INDEXES & USER_SEGMENTS
data dictionary view, I stumbled upon this phenomenon, which shows two 
different results as far as the byte allocation is concerned, which I
could


not comprehend. Any insight would be appreciated.



USER_INDEXES






Index Name    Table Name   Initial Ext   Next Ext   Min. Ext.   PCT
Increase  


----------    ----------   -----------   --------   ---------  





CUST_PK       CUSTOMER           36864      40960          
1             50
ORDER_PK      ORDER              12288      40960          
1             50






USER_SEGMENTS






Segment Name      Bytes   Extents


------------   --------   -------



CUST_PK           40960         1
ORDER_PK          28672         1





My question is shouldn't the BYTES column in the USER_SEGMENTS show
38684 & 12288. 


Why is the bytes column displayed as 40960 & 28672, when the formula to
calculate 


the bytes allocated in this case (only one extent allocated) should be 



    (number of extents) X (initial extent)



ie.,                1   X  36864           = 36864 bytes
                    1   X  12288           = 12288 bytes





Thanks for your time and reply.



-Prakash


Received on Fri Feb 06 1998 - 00:00:00 CET












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