I have the following data stored in the database column xyz:
a=222223333;b=433333657675457;c=77777;
a=52424252424242;d=5353535353;b=7373737373;
There is no requirement that b value should always be there but if b value is present I have to retrieve the value following b=.
I want to retrieve the value of b using regular expressions in Oracle and I am unable to do it.
Can anyone please help me find a solution for this?
I suggest using Oracle built-in function REGEXP_SUBSTR which returns a substring using regular expressions. According to the example you posted, the following should work.
SELECT REGEXP_SUBSTR(xyz, 'b=\d+;') FROM your_table
You can use regexp_substr:
select substr(regexp_substr(';' || xyz, ';b=\d+'), 4) from your_table;
Concatenation with ; is to distinguish between key-value pair with key say 'ab' and 'b'.
Use a Subexpression to Select a Substring of Your REGEXP_SUBSTR Matching Pattern
My match pattern, 'b=(\d+);', includes the parenthesis which mark this subexpression which is the last parameter of REGEXP_SUBSTR.
If you look at the 12c documentation, you will see that the third example uses a subexpression.
The escaped d just is a regular expression shorthand to indicate that we are looking for digits and the plus symbol is a quantifier indicating 1 or more digits.
SCOTT@db>WITH smple AS (
2 SELECT
3 'a=52424252424242;d=5353535353;b=7373737373;' dta
4 FROM
5 dual
6 ) SELECT
7 dta,
8 regexp_substr(a.dta,'b=(\d+);',1,1,NULL,1) subexp
9 FROM
10 smple a;
DTA subexp
---------------------------------------------------------
a=52424252424242;d=5353535353;b=7373737373; 7373737373
above solution is working in all the cases even if b contains alphanumeric
b value. Also please post actual code, not screenshots.