Maximum String Length for Common Database Fields

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.

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  Character Length
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  Example
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  254
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  see RFC5321
</td>

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  189
</td>

<td>
  Longest City Name is Bangkok in Thai: Krung Thep Mahanakhon Amon Rattanakosin Mahinthara Ayuthaya Mahadilok Phop Noppharat Ratchathani Burirom Udomratchaniwet Mahasathan Amon Piman Awatan Sathit Sakkathattiya Witsanukam Prasit
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<td>
  18
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  Country with the longest zip code format is Chile with NNNNNNN, NNN-NNNN
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<td>
  90
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  Longest country name is Libya&#8217;s Arabic name prior to 2013: al-Jam-h-riyyah al-‘Arabiyyah al-L?biyyah ash-Sha‘biyyah al-Ishtir-kiyyah al-‘U-má
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