调试错误（PHP+MySQL）在线等

Warning:in_array() [function.in_array]:Wrong datatype for second argumentWarning:Invalid argument supplied for fareach()Notice:empty set columnnotice:DB Error:unknown error表的字段为 id (int(11));question(varchar(100));answer(varchar(255))添加的时候id能写入，后面2个字段无法写入出现上面的错误怎么解决，