Question

Consider a table category in a database, with column typeis. The datatype is varchar with values

         typeis
         ------
         2.5.1
         12
         1.1.1
         11
         letters12
         .........

I want to write a query that only returns records with “.” and numbers from 0-9

For example

         2.5.1
         1.1.1

So far, I have

       select typeis from category where typeis
       not in 
       (select typeis from category where typeis REGEXP  '[^0-9 \.]+')
       and typeis in
       (select typeis from category where typeis REGEXP  '^[0-9]+[\.]')

which seems to work. The problem is that it takes over 3secs for just 1500 records. I would like to make it simpler and faster with just one REGEXP, instead of having nested select

Answer 1

Try: ^[0-9]+\.[0-9]+(\.[0-9]+)*

This should match things starting with a number(s) including a dot somewhere in the middle, and ending with numbers, and as many of these patterns as it would like.