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Home -> Community -> Mailing Lists -> Oracle-L -> DUPLICATE VALUE CHECK
Hi all
i have one column in my table (in which daily 100000 rows are added to the table) which has values like
XYZ_A_LO0000_0000001 XYZ_A_LO0000_0000002 XYZ_A_LO0000_0000003 XYZ_A_LO0000_0000004 XYZ_A_LO0000_0000005 XYZ_A_LO0000_0000006 XYZ_A_LO0000_0000007 XYZ_A_LO0000_0000008 XYZ_A_LO0000_0000009
i want to check duplicate values.. there are 2 cases of duplication
Case I :- i am using the following query
select from my_table where rowid not in(
select max(rowid) from my_table
group by my_column_name );
i am getting the rows which are duplicate ..
CASE II : - i want to check duplication in last 7 characters(which are actually nos) in my column like
0000001
0000002
0000003....so on....
i am using substr function to get this value and i am checking the values with remaining rows..
but as the table contains nearly 450000(present rowcount) the query is taking lot of time...which i can't afford... the column has index on it.
plz suggest me what to do??
Shirish Khapre, SE Rolta India Ltd.
Off Ph No. (+91) (022) 8326666,8262222,8300568
Ext'n 2730
Minds are like parachutes. They only function when they are open
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Author: Shirish Khapre
INET: shirish_at_rolta.com
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