T-SQL SELECT语句

Question

I have a simple question regarding SELECT statement in SQL Server. I would like to know the purpose of the following syntax:

SELECT column_name, . *

I don't understand the purpose of the (period) and a (star) after the SELECT . I understand SELECT column_name1, column_name2,.... etc. or SELECT *... but what does a period do before the star.

Answer 1

That is invalid syntax and will not run.

.* can be used following a table name or alias to get all columns for that table. For example...

SELECT mytable.* FROM mytable

or

SELECT a.column_one, a.* FROM mytable a