Select record between two IP ranges

Question

I have a table which stores a ID, Name, Code, IPLow, IPHigh such as:

1, Lucas, 804645, 192.130.1         


        

Answer 1

Painfully. SQL Server has lousy string manipulation functions. It does, however, offer parsename(). This approach converts the IP address to a large decimal value for the comparison:

select t.*
from (select t.*,
             (cast(parsename(iplow, 4)*1000000000.0 as decimal(12, 0)) +
              cast(parsename(iplow, 3)*1000000.0 as decimal(12, 0)) +
              cast(parsename(iplow, 2)*1000.0 as decimal(12, 0)) +
              cast(parsename(iplow, 1) as decimal(12, 0))
             ) as iplow_decimal,
             (cast(parsename(iphigh, 4)*1000000000.0 as decimal(12, 0)) +
              cast(parsename(iphigh, 3)*1000000.0 as decimal(12, 0)) +
              cast(parsename(iphigh, 2)*1000.0 as decimal(12, 0)) +
              cast(parsename(iphigh, 1) as decimal(12, 0))
             ) as iphigh_decimal
      from t
     ) t
where 192168002050 between iplow_decimal and iphigh_decimal;

I should note that IP addresses are often stored in the database as the 4-byte unsigned integers. This makes comparisons much easier . . . although you need complicated logic (usually wrapped in a function) to convert the values to a readable format.