Question

I would like to query a table where I am comparing against a regular expression and then of those results I want to filter out any that begin with 999

Here’s the query I have, but this returns no results:

Select * FROM my_table 
WHERE REGEXP_LIKE(my_row, '[a-zA-Z]') 
AND my_row NOT LIKE '999%'

Any ideas where I’m going wrong with this? I know that I should be getting several results.

Sample date would be like the following…

my_row
______

12345
45673
G12354
1234B
999RT

Answer 1

Given this test data:

create table my_table (id number, my_row varchar2(10));

insert into my_table values (1, '7878')
/
insert into my_table values (2, 'THIS')
/
insert into my_table values (3, 'and this')
/
insert into my_table values (4, '999NOTthis')
/

Your query returns these results:

ID     MY_ROW
--     ------
2      THIS
3      and this

Here’s a SQL Fiddle to prove it.

These seem to be the rows we would expect to be returned by your logic so the problem is clearly in your data.