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Oracle table partitions

Hi,

Iam working on oracle table partitions and need to provide a training on the types of partitions , I need the below information in regard to oracle hash partition

1. How does hash linear algorithm work , any example should be fine. I need an detailed explanation on how oracle applies Linear hash algorithm for each table partition using HASH .

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Naitik Gamit

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Swaminathan K

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hi Naitik,

Can you explain me how the partitions are derived using the steps mentioned in the url above

I have followed the below steps to validate the Linear HASH algorithm

create table hash_tab
(
id number ,
name varchar2(40))
partition by hash (id)
partitions 4;

Below are the partitions created in oracle after the above statement

SYS_P25
SYS_P26
SYS_P27
SYS_P28

Analyze the tables so that the num_rows column in user_tab_partitions is updated.

Insert into hash_tab values (&i,'&n');

Values inserted are
1,sdsd
45,sdfsdf
34,dfgdfg
24,dssdf

I tried to validate the algorithm logic mentioned in the above url mentioned , iam not able to derive the correct partition into which oracle inserts the records But I noticed , it starts inserting into the last partition SYS_P28

Below is the sample logic using the algorithm mentioned in the above url
num=4 --> no of partitions
v=power(2*ceil(log(2,4))); --> 4
n=f(column_value) & (v-1) --> 1 & (4-1) = 1 &3 =1

but the value 1 is getting inserted into 4th partition SYS_P28 instead of SYS_P25

Any help with the algorithm mentioned in the url is really appreciated.
This I need for training purpose

SOLUTION

MikeOM_DBA