'?': match exactly zero or one repetition : Wild Card « Regular Expressions « Oracle PL / SQL






'?': match exactly zero or one repetition

SQL> --'?': match exactly zero or one repetition
SQL>
SQL> SELECT REGEXP_SUBSTR('Yababa dababa do','a.?a') FROM dual;

REG
---
aba

SQL>

           
       








Related examples in the same category

1.'.' matches anything
2.REGEXP_INSTR(description,'F.')
3.REGEXP_INSTR(description,'e.e'): Find a letter and then whatever until there was another of the same letter
4.REGEXP_INSTR(description,'i.i'): 'i' followed by any one character, followed by another 'i'
5.REGEXP_SUBSTR('Yababa dababa do','a.a')
6.REGEXP_SUBSTR('abbbb','ab+')
7.REGEXP_SUBSTR('a','ab+')
8.REGEXP_SUBSTR('abbbb','ab*') (2)
9.To see the difference between '*' and '+'
10.'+': match one or more repetitions
11.'*' (match zero or more repetitions)
12.REGEXP_INSTR(description, 'e.+e'): An 'e' followed by any number of other characters and then another 'e'
13.REGEXP_SUBSTR(description,'e.*e')
14.Use the non-greedy '?'