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* expr [ [ AS ] [ ' ] column_alias [ ' ] ]
SELECT
Specifies a list of expressions, called a select list, whose results will form columns
of the result table. Typically, the expression is a column name from a table named in
the FROM clause. The expression can also be any supported mathematical expression,
scalar function, or aggregate function that returns a value.
The optional column_alias argument specifies a new heading for the associated
column in the result table. You can also use the column_title in an ORDER BY clause.
Enclose the new title in single or double quotation marks if it contains spaces or other
special characters, including hyphens.
Note: A table alias cannot be used to qualify a column alias. A column alias can only
be used without a qualifier because it is not a part of any table definition.
[ table | alias.]column_name , ... ]
Specifies a list columns from a particular table or alias.
Examples Both these statements return all the columns in the customer table to the select list:
SELECT * FROM Customer;
SELECT Customer.* FROM Customer;
The table_name.* syntax is useful when the select list refers to columns in multiple tables and
you want to specify all the columns in one of those tables. For example:
SELECT Customer.CustNum, Customer.Name, Invoice.*
FROM Customer, Invoice ;
The following example illustrates using the column_alias option to change the name of the
column:
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