Efficient query to fetch the columns in an entire relation?

Hello,

Yesterday, I came across one simple question yet interesting.

What is the best way of retrieving all columns in a given relation using a SQL query.

Two possible alternatives are

1. SELECT * FROM relation_name;
2. SELECT COLUMN1, COLUMN2, ..., COLUMNn FROM relation_name;

I am not able to decide, which is better than the other and more importantly
WHY? Hope to get some reply on this,

• Vijay