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SQL-92
Guide and Reference
COLUMN_LIST Clause
Specifies which columns to retrieve by the SELECT statement.
SYNTAX
[ ALL | DISTINCT ]
Indicates whether a result table omits duplicate rows. ALL is the default and specifies that the result table includes all rows.
DISTINCT
specifies taht a table omits duplicate rows.* | { table_name. | alias. } *
Specifies that the result table includes all columns from all tables named in the FROM clause.
* expr [ [ AS ] [ ' ] column_title [ ' ] ]
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_title’
argument specifies a new heading for the associated column in the result table. You can also use the column_title in anORDER
BY
clause. Enclose the new title in single or double quotation marks if it contains spaces or other special characters.[ table | alias.]column_name , ... ]
Specifies a list columns from a particular table or alias.
EXAMPLESBoth these statement return all the columns in the customer table to the select list.
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:
The following example illustrates using the column_title option to change the name of the column.
You must qualify a column name if it occurs in more than one table specified in the
FROM
clause:
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