The SQL Select Statement is used to select the data from the database. So the data Which are returned is stored in the result table which is called a result-set.
You can select the columns in multiple ways for example if you want all the columns of the particular table, you can use * to return all columns and if you need selected ones then you can define it.
*
Select statement: All Columns
SELECT * FROM table_name
Select statement: Selective Columns
SELECT column_1, column_2, column_3 FROM table_name
SELECT * FROM customers
SELECT customerName, sales FROM customers