关于在期望条件的上下文中指定的非布尔类型的表达式的混淆

I am fallowing an example .I have a field named Deleted in the db. .When I click the delete button actually not deleting data just replcaing "N" with "Y" value The problem is i downloaded the source code It works but after slightly changed I get this exception.I am wondering what am i doing wrongI am fallowing an example .I have a field named