Why is using '*' to build a view bad?

Question

Why is using \'*\' to build a view bad ?

Suppose that you have a complex join and all fields may be used somewhere.

Then you just have to chose fields needed

Answer 1

Another reason why "*" is risky, not only in views but in queries, is that columns can change name or change position in the underlying tables. Using a wildcard means that your view accommodates such changes easily without needing to be changed. But if your application references columns by position in the result set, or if you use a dynamic language that returns result sets keyed by column name, you could experience problems that are hard to debug.

I avoid using the wildcard at all times. That way if a column changes name, I get an error in the view or query immediately, and I know where to fix it. If a column changes position in the underlying table, specifying the order of the columns in the view or query compensates for this.