mysql - Check to see if an ID exists in a database -


When an ID number is given, I want to see if it exists in the database or not. If the ID is received then the truth will return, and if not, then return the wrong.

My knowledge of MySQL is very low, but I'm assuming that it might be something to do with the COUNT (*) function? $ id = $ id 

  Select table from id 
 get fancy is not needed. Being present with Subqueries is likely to generate poor performance only, but I am happy if I have been shown otherwise.

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