Question

I want to use the Oracle REGEXP_REPLACE to remove some dots from a String.
I have to remove from the second dot if exists.
For example:

4       => 4
5       => 5
5.1     => 5.1
5.1.1   => 5.11
5.1.2   => 5.12
5.1.2.1 => 5.121
5.1.2.2 => 5.122
6       => 6

I have this

select REGEXP_REPLACE(num, '(\d+)(\.)(\d+)(\.)(\d+)', '\1.\3\5')
from my_table;

the problem is that my query is made just for two dots. If the string has more than two dots, I have to modify the query to accept more dots and so.
Is there any way to do this automatically?

Thanks

Answer 1

A posible “dirty” solution

select REGEXP_REPLACE(num, '(\d+)(\.)(.*)', '\1\2') || 
       REPLACE( REGEXP_REPLACE(num, '(\d+)(.*)', '\2') ,'.','') 
from my_table;

and although it’s not at all clear, it works.