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DISTINCT, SUBSTR & MAX in Oracle Database

I have a table like below on which I want to return the distinct server name with max value of last 4 digits from all permutations in that table:

ServerName
APPQTV1234
IISLUG60DF
XCCPTV401D

SO basically I can get the unique combination using following query:

select DISTINCT SUBSTR(ServerName,1,6) from MYTABLE;

This gives me:

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ServerName
APPQTV
IISLUG
XCCPTV

Now I want the query to return max values of last 4 digits which are basically incremental in HEX

Any suggestions would help! Thanks in advance

EDIT 1
Expected Result would be like:

So if table has these values:

ServerName
APPQTV1234
IISLUG6578
XCCPTV7894
APPQTV4321
IISLUG9999
XCCPTV8049

Then query should return max value for each combination. For e.g:

ServerName
APPQTV4321
IISLUG9999
XCCPTV8049

>Solution :

We can use the ‘XX’ format mask with to_number() to convert hex into decimal. The number of X must match the number of characters in the hex string. Then it’s a simple aggregation.

with mytable as (
select 'APPQTV1234' as servername from dual union all
select 'APPQTV1C34' as servername from dual union all
select 'IISLUG60DF' as servername from dual union all
select 'IISLUG80DF' as servername from dual union all
select 'XCCPTV401D' as servername from dual 
)
select SUBSTR(ServerName,1,6) as server_name
      ,max(to_number(substr(servername, 7, 4), 'xxxx')) as server_no
from MYTABLE
group by SUBSTR(ServerName,1,6)

Demo on db<>fiddle

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