accessing encryped data from a mysql table
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I am trying to access data from am mysql table which is base_64 encoded, but I get a "Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in......"
When I try it with md5 accessing md5 hashed data it works fine, cant figure it out.Thanks, Here's the code: 

    ("SELECT * FROM users WHERE email= base64_decode('$email')");