INDEX [message #326206] |
Tue, 10 June 2008 12:11 ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
ORAGENASHOK
Messages: 240 Registered: June 2006 Location: Chennai
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Senior Member |
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can anybody give the reference url for index from basis
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Re: INDEX [message #326610 is a reply to message #326208] |
Thu, 12 June 2008 02:06 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
ORAGENASHOK
Messages: 240 Registered: June 2006 Location: Chennai
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Senior Member |
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I have created one index with how can i know the type of the index ( bitmap or btree...) .
or if i am wrong anything on above can anyone tell me how i known one particular index type (bitmap or btree ... )
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Re: INDEX [message #335904 is a reply to message #326208] |
Thu, 24 July 2008 02:36 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
ORAGENASHOK
Messages: 240 Registered: June 2006 Location: Chennai
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Senior Member |
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Michel,
According to the database concept references that the oracle uses b-tree to store the indexes
In that references there are two blocks
1. Branch Block
2. Leaf Block
The oracle process will be parallel for table and index at the time of inserting /retriving the data from/to table which is indexed.
My doubt is how internally oracle assign value for the branch block.
for example : i have created index for column staff_name
staff_name values are :
Ashok
krish
michel
rioot
suresh
kannan
sundar
can you please explain in detail how and what data will be stored into branch block and leaf block
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Re: INDEX [message #335987 is a reply to message #335920] |
Thu, 24 July 2008 05:43 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
ORAGENASHOK
Messages: 240 Registered: June 2006 Location: Chennai
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Senior Member |
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I have given below the words which is given for explain about the branch block.
Branch blocks store the following:
The minimum key prefix needed to make a branching decision between two keys
The pointer to the child block containing the key
My question is whether all the column value which is indexed in the table will be inserted into the branch block for search.
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Re: INDEX [message #335997 is a reply to message #335991] |
Thu, 24 July 2008 06:18 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) ![Go to next message Go to next message](/forum/theme/orafaq/images/down.png) |
ORAGENASHOK
Messages: 240 Registered: June 2006 Location: Chennai
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Senior Member |
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You mean for example in my table the indexed column values are
staff_name :
==============
Ashok
krish
Ashok
suresh
kannan
Ashok
and i fire one select query which is given below
select emp_no,statff_name,designation from emp where
staff_name='Ashok';
According to your explanation the Ashok will be taken as a key value in the branch block and first,third and sixth row of the value and corresponding rowid will be in the leaf block and corresponding rows are displayed as the result set for the query am right
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Re: INDEX [message #336000 is a reply to message #335997] |
Thu, 24 July 2008 06:42 ![Go to previous message Go to previous message](/forum/theme/orafaq/images/up.png) |
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Michel Cadot
Messages: 68675 Registered: March 2007 Location: Nanterre, France, http://...
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Senior Member Account Moderator |
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A branch block points to N leaf blocks. For each block, the branch contains the minimum key value for this block.
A leaf block contains the key value and the rowid for each row.
Regards
Michel
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