When designing a database schema you often have to make decisions on a fields length. Rather then just guess at a number, use the maximum possible value that could conceivably be used for the field. Below is a chart of common database fields such as email address, city, zip code and country name and the maximum possible length value that can be used. Field Name Character Length Example email address 254 see RFC5321 city 189 Longest City Name is Bangkok in Thai: Krung Thep Mahanakhon Amon Ratt...
