RegExp_like

This will match: a, a-a, aaa-a, aaa-a-aaa-a-aaa-a, etc

But not: -, -a, a-, a--a, a-a-a-, a-a--a, etc. 

^[a-zA-Z0-9]+(-[a-zA-Z0-9]+)*$

^[[:alnum:]\-]+$

select 1

from dual

where not REGEXP_LIKE ('-11-6734-9-7-', '^[a-zA-Z0-9]+(-[a-zA-Z0-9]+)*$')

/

select 1

from dual

where REGEXP_LIKE ('1167349@', '[^[:alnum:]]')

/

SELECT

CASE

WHEN  REGEXP_LIKE ( '11-6734-@9'

        , '^[ [:alnum:]\-]+$'

  )

THEN  'Okay'

END AS okay

FROM dual

---ADF side--

^[0-9]*$  -- allows numbers only

[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,9} -- invalid email

[a-zA-Z0-9]

[\w]* --> allows only alpha numeric

[\w]*\- -> allowing only - , 78gh-, 

[\w]*+\-  --> allowing only - , 78gh-,fghj67-

[\w]\-  --> not allowing any thing

[a-z A-Z 0-9-] --> not working allowing all

[a-z A-Z 0-9 _] --> not allowing any thing

[A-Za-z0-9-] --> not allowing any thing

[A-Za-z0-9.-] --> not allowing any thing

[a-zA-Z0-9\-] --> allowing only -

[a-zA-Z0-9]+\-  -->  allowing fg7-

[a-z\-A-Z\-0-9]  --> only allowing -

[a-zA-Z0-9_\-]\w+ --> allowing  gh7,gh7_, gh_7_, _gh_7_ , -gh_7_    not allowed gh7-,gh-7, g-h_7_

[a-zA-Z0-9_-]+  --> allowing -dfghj-7- , 78-98-56 , 7_8-98-56

 

final 

[a-zA-Z0-9-]+  --> allowing -a-5- , 78-89-000  not allowing -a-5@ , 78-89-000_

^[a-z]+[a-z-]*[a-z]+$