backend developer interview questions

. Conversely, when Getfullname () is assigned to the test variable, the context refers to the Global Object (window). This is because test is a property that is implicitly set to the global object. For this reason, the function returns the FullName of the window, that is, the value defined in the first row.Question 5:call () and apply ()Now let you solve the previous problem and make the final Console.log () print Aurelio De Rosa.　　ReplyThe problem can change the function context by forcing the

security.Even so far, some people don't even know the basic semantics of SQL syntax.String sql = "SELECT * from Tb_name where name= '" +varname+ "' and passwd= '" +varpasswd+ "'";If we pass [' or ' 1 ' = ' 1] in as varpasswd. User name feel free to see what will become?SELECT * from tb_name = ' random ' and passwd = ' or ' 1 ' = ' 1 ';Because ' 1 ' = ' 1 ' is sure to be true, so you can pass any validation. What's more:Put [';d rop table tb_name;] Incoming in as VARPASSWD:SELECT * from tb_name