DOUBT - Oracle command to REPLACE data

   I have the following issue:

   I need to store a column VARCHAR2(45).

   If I am inserting data for first time I can , for example, save something like this:

      111110000000000000000000000000000000000000000

   When the line exists recorded in the table with the content above, and during my process I must updated the following, considering only character 1:

      000000000000000000000000000000101010101010100

   The final result must be as below, replacing only the character 1:

      111110000000000000000000000000101010101010100

  I know that I can do it:
     WHILE X < Y
       LOOP
         FINAL COLUMN := SUBSTR(N) || 1 || ....
      END LOOP;

 But is there any other way to do it, like regular expression or another command / instruction ?

Regards
Eriovaldo

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