How to update specific records in 03 tables

Question

i have 03 tables test1 test2 and test3 all 03 tables have a common column (referenced) 'code' there are thousands of records in these 03 columns of 03 tables but some records(old records) were not tagged with 1905 like 6789123 i want to tagged 1905 with these old records such as 19056789123 i am using oracle 10g.
thanks in advance
Edited by: user8765528 on May 25, 2011 11:51 AM
Edited by: user8765528 on May 25, 2011 11:55 AM

Answer 1

Like this?
UPDATE table1
   SET code   =
          REGEXP_REPLACE (code,
                          '^(0{0,4})(.*)',
                          '0000\2')
WHERE NOT REGEXP_LIKE ( code, '^0{4}')What I am doing above is if the code does not start with four zeroes , I am adding 4 zeroes.
Also considering that if the code starts with 3 zeroes I am adding only one zero etc.
You can do the same for rest of the tables.
Example. I will be only touching the forst two rows and will be updating them. Row3 is already fine,
SQL> WITH T AS (SELECT '11231' code FROM DUAL UNION ALL
  2             SELECT '0011232' code FROM DUAL UNION ALL
  3             SELECT '000011233' code FROM DUAL)
  4  SELECT REGEXP_REPLACE (code,
  5                         '^(0{0,4})(.*)',
  6                         '0000\2') code
  7    FROM T
  8   WHERE NOT REGEXP_LIKE ( code, '^0{4}');
CODE
000011231
000011232
SQL> Edited by: Ganesh Srivatsav on May 25, 2011 1:32 PM