Question

a query returns string like AAA[][]AAA[][][][]BBB[][]BBB . I need to replace the four consecutive carriage returns with a semicolon but not the consecutive two carriage returns. I have tried

replace(STRING,chr(13)||chr(13)||chr(13)||chr(13),';')

but it has no effect. Any help would be appreciated.

Answer 1

Use CHR(10) on linux/unix systems. On Windows, the carriage returns are composed of two characters CHR(10)||chr(13). On linux:

SQL> WITH DATA AS (
  2     SELECT 'AAA
  3  
  4  AAA
  5  
  6  
  7  
  8  BBB
  9  
 10  BBB' txt FROM dual
 11  ) SELECT replace(txt, chr(10)||chr(10)||chr(10)||chr(10), ';') rep
 12      FROM DATA;

REP
------------------------------
AAA

AAA;BBB

BBB

Since you you can use newlines directly in expressions, you can make it work on all platforms/character sets with newline characters (I would recommend this solution since it’s portable):

SQL> WITH DATA AS (
  2     SELECT 'AAA
  3  
  4  AAA
  5  
  6  
  7  
  8  BBB
  9  
 10  BBB' txt FROM dual
 11  ) SELECT replace(txt, '
 12  
 13  
 14  
 15  ', ';') rep FROM DATA;

REP
--------------------------
AAA

AAA;BBB

BBB