Question

I need a regular expression in MySQL that matches:

• a sentence that has a word
• that begins with e
• ends with k
• can contain [deki] (doesn’t have to include all)
• is 3-4 characters long

For example, the following would match:

• “My name is eik“
• “the edik of doom”
• “herp derp eidk derp”

Answer 1

MySQL’s extended regular expressions are pretty powerful; see http://dev.mysql.com/doc/refman/5.6/en/regexp.html. You can write:

[[:<:]]e[deki]{1,2}k[[:>:]]

(boundary-at-start-of-word, plus e, plus one or two characters from [deki], plus k, plus boundary-at-end-of-word).

This assumes that your words are separated by punctuation or spaces or whatnot, and it doesn’t require that your field contain multiple words.

(Hat-tip to Bohemian for giving an answer that used \b. MySQL doesn’t support \b for word-boundaries, but it reminded me of things my original answer missed.)