SQL 标准中是否存在 INTERSECT 运算符？

Question

SQL 标准中是否存在 INTERSECT 运算符？如果存在，是否为可选运算符？

请留下可靠的来源。

Answer 1

你的教授要么错了，要么你误解了他们说的话。 SQL 的每个实现不支持 INTERSECT，但它是标准。

我检查了我的 "Understanding the New SQL: A Complete Guide" by Jim Melton and Alan R. Simon (1993) 副本，其中涵盖了 SQL-92。

第 171 页说：

The INTERSECT and EXCEPT Operators

INTERSECT returns all rows that exist in the intersection of two tables; that is, in both tables.
SELECT * 
  FROM music_titles
INTERSECT
SELECT * 
  FROM discontinued_albums;
The preceding query will return, for example, all discontinued albums that have been re-released.

这是 link 到 Google 的书籍，在搜索中突出显示了单词 INTERSECT：https://www.google.com/books/edition/Understanding_the_New_SQL/ZOOMSTZ4T_QC?bsq=intersect&gbpv=1

我还查看了 "SQL-99 Complete, Really" by Peter Gulutzan and Trudy Pelzer (1999) 的副本。它还记录了 INTERSECT.

Answer 2

INTERSECT 包含在 ANSI/ISO SQL 标准中 (ISO/IEC 9075-2:2016(E)) , 作为可选功能 F302:

F302 INTERSECT table operator

F302-01 INTERSECT DISTINCT table operator
F302-02 INTERSECT ALL table operator

SQL 标准中是否存在 INTERSECT 运算符？

Does INTERSECT operator exist in the SQL standard?

sql

ansi-sql

intersect