sql server - SQL Like filtering -

welcome!

i working on c# , encountered rather silly issue. need fill listbox data database obviously. problem varchar filtering. need filter codes , display right ones.

example of codes are: rrtt, rrtr, rt12, rq00, r100, r200, r355, ty44, gg77 etc. 4 digit codes.

i managed filter r-codes simple select * table1 code_field 'r%' both r000 , rq10 , need r ones followed numbers only.

so example:

rrtt, rrtr, rt12, rq00, r100, r200, r355 

only:

r100, r200, r355 

any ideas should add like 'r%'?

in sql server, can make use of wildcards. here 1 approach:

where rcode 'r___' ,       -- make sure code has 4 characters       rcode not 'r%[^0-9]%'  -- , nothing after first 1 not number 

or:

where rcode 'r[0-9][0-9][0-9]' 

in other databases, using regular expressions rather extensions like.