REGEXP gives different outputs - sql

Question

I've used REGEXP to find text patterns, but I'm having a problem with one part of it. I'd like to classify a ticketing fare calculation line as having only 1 of the following labels:
blank (there are no Q surcharges)
QCPN (there are only instance(s) of the existing format Q20.00)
QPRO (there are only instance(s) of the new additional format Q LONSYD20.00)
QBOTH (there are examples of both QCPN and QBOTH)
Below SQL:
SELECT JOUR.JOUR_FSERNR
AS TICKET,
CASE
WHEN REGEXP_LIKE (
JOUR.JOUR_FCA1LN
|| JOUR.JOUR_FCA2LN
|| JOUR.JOUR_FCA3LN
|| JOUR.JOUR_FCA4LN,
'Q[[:space:]][[:alpha:]]{6}')
THEN
'QPRO'
WHEN REGEXP_LIKE (
JOUR.JOUR_FCA1LN
|| JOUR.JOUR_FCA2LN
|| JOUR.JOUR_FCA3LN
|| JOUR.JOUR_FCA4LN,
'Q[[:digit:]]+\.[[:digit:]]+.*END')
THEN
'QCPN'
WHEN REGEXP_LIKE (
JOUR.JOUR_FCA1LN
|| JOUR.JOUR_FCA2LN
|| JOUR.JOUR_FCA3LN
|| JOUR.JOUR_FCA4LN,
'Q[[:space:]][[:alpha:]]{6}')
AND REGEXP_LIKE (
JOUR.JOUR_FCA1LN
|| JOUR.JOUR_FCA2LN
|| JOUR.JOUR_FCA3LN
|| JOUR.JOUR_FCA4LN,
'[[ALPHA]]{3}Q[[:digit:]]+\.[[:digit:]]')
THEN
'QBOTH'
ELSE
NULL
END
AS QTYPE,
( (JOUR.JOUR_FCA1LN || JOUR.JOUR_FCA2LN) || JOUR.JOUR_FCA3LN)
|| JOUR.JOUR_FCA4LN
AS FARECALC
FROM "S00BJOUR" JOUR
WHERE JOUR.JOUR_FSERNR = '9999889652'
If you look at the above SQL and find the CASE WHEN line that outputs 'QCPN', you'll see there's an "END" text string 'Q[[:digit:]][[:graph:]]END'. I put ‘END’ in there because I only want the REGEXP to look to the left of 'END' in a fare calc line.
But it gives me some incorrect outputs as shown in the attached image Incorrect Outputs in RED:
Any help to have this corrected is much appreciated.

Answer 1

It feels strange, you don't put so much quantifier. Like QCPN, whathever it means shoudld be :
Q[[:digit:]]{2}\.[[:digit:]]{2}
To match your Q20.00 example at least.
EDIT :
In your "with end exemple", didnt work because you dont put any quantifier :
Q[[:digit:]][[:graph:]]END
#Match Q5.END, Q22END, Q8AEND
#Dont match Q20.00 END
But :
Q[[:digit:]]+\.[[:digit:]]+.*END
#Match "Q1.2 ZA VD END Q20.2"
#Dont match "Q5.END", "BF END Q10.25"
For the second problem, QPRO/QBOTH, the probleme is :
Q HAMAOQ20.00
Try
[[:space:]]Q[[:digit:]]+\.[[:digit:]]+.
For QCPN regex.