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02.21.2007 at 05:53AM PST, ID: 22403311
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8.4

Select Unique Row based on specific columns. - Distinct?

Asked by obrienj in Oracle Database, Oracle 10.x

Tags: , , , ,

Quick one.  Just curious if the Distinct command in a select statement can be used only for particular columns.
e.g.
Lets say I have a table:
Table1
Col1
Col2
Col3
Col4


Now I want to select all columns from this table, but I want to make sure that the rows selected are Distinct based on two of the Columns
i.e.  Col2,Col3

So generally to select distinct rows I would have something like:
select distinct co2,col3 from table1
-> but this will only return those columns.  And if I put it like
select distinct col1,co2,col3, col4 from table1  
I will only get unique rows based on all the columns - this is not what I want.

so pseudo code to get what I wish to achieve would possible look something like:
select col1, distinct[col2,col3],col4 from table1  

This line would make sure that the [col2,col3] combination would be unique in the output.

What would the best way to do this be?  Perhaps a there is an alternative function to do this... or maybe a sub-query of sorts would be best.
Any advice welcomed,
j
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[+][-]02.21.2007 at 06:04AM PST, ID: 18578309

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Zones: Oracle Database, Oracle 10.x
Tags: select, unique, distinct, row, columns
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Solution Provided By: cjjclifford
Participating Experts: 2
Solution Grade: A
 
 
[+][-]02.21.2007 at 06:05AM PST, ID: 18578325

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[+][-]02.21.2007 at 06:11AM PST, ID: 18578366

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[+][-]02.21.2007 at 06:15AM PST, ID: 18578408

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[+][-]02.21.2007 at 06:18AM PST, ID: 18578435

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