选择语句是否属于 Transact-SQL(T-SQL)类别,是 Microsoft 和 Sybase 对 SQL 的专有扩展。
答案1
MS T-SQL 选择:http://msdn.microsoft.com/en-us/library/ms189499.aspx
SELECT [ ALL | DISTINCT ]
[TOP ( expression ) [PERCENT] [ WITH TIES ] ]
< select_list >
[ INTO new_table ]
[ FROM { <table_source> } [ ,...n ] ]
[ WHERE <search_condition> ]
[ <GROUP BY> ]
[ HAVING < search_condition > ]
ANSI SQL 选择: http://www.rawos.com/odbc/sqlguide/index.html
SELECT [DISTINCT|ALL] *|{attr_name[ AS new_attr_name]} FROM {table_or_view[ alias]}
[ WHERE where_criteria]
[ GROUP BY {attributes}[ HAVING condition]]
[ ORDER BY {attrname|attrorder [ASC|DESC]}]
[ INTERSECT|UNION[ ALL] SELECT_statement]
是的,T-SQL Select 是 ANSI Select 的扩展版本(因此可能是专有版本)。