query_expression_body INTERSECT [ALL | DISTINCT] query_expression_body
    [INTERSECT [ALL | DISTINCT] query_expression_body]
    [...]

query_expression_body:
    See Section 15.2.14, “Set Operations with UNION, INTERSECT, and EXCEPT”

INTERSECT 限制多个查询块的结果仅限于所有查询块共有的行。示例：INTERSECT limits the result from multiple query blocks to those rows which are common to all. Example:

mysql> TABLE a;
+------+------+
| m    | n    |
+------+------+
|    1 |    2 |
|    2 |    3 |
|    3 |    4 |
+------+------+
3 rows in set (0.00 sec)

mysql> TABLE b;
+------+------+
| m    | n    |
+------+------+
|    1 |    2 |
|    1 |    3 |
|    3 |    4 |
+------+------+
3 rows in set (0.00 sec)

mysql> TABLE c;
+------+------+
| m    | n    |
+------+------+
|    1 |    3 |
|    1 |    3 |
|    3 |    4 |
+------+------+
3 rows in set (0.00 sec)

mysql> TABLE a INTERSECT TABLE b;
+------+------+
| m    | n    |
+------+------+
|    1 |    2 |
|    3 |    4 |
+------+------+
2 rows in set (0.00 sec)

mysql> TABLE a INTERSECT TABLE c;
+------+------+
| m    | n    |
+------+------+
|    3 |    4 |
+------+------+
1 row in set (0.00 sec)

如同 UNION 和 EXCEPT除非，如果既不指定 DISTINCT指定 ALL，默认为 DISTINCT。As with UNION and EXCEPT, if neither DISTINCT nor ALL is specified, the default is DISTINCT.

DISTINCT 可以从交集两侧移除重复，如图所示：DISTINCT can remove duplicates from either side of the intersection, as shown here:

mysql> TABLE c INTERSECT DISTINCT TABLE c;
+------+------+
| m    | n    |
+------+------+
|    1 |    3 |
|    3 |    4 |
+------+------+
2 rows in set (0.00 sec)

mysql> TABLE c INTERSECT ALL TABLE c;
+------+------+
| m    | n    |
+------+------+
|    1 |    3 |
|    1 |    3 |
|    3 |    4 |
+------+------+
3 rows in set (0.00 sec)

（TABLE c INTERSECT TABLE c 是前述两个语句中的第一个的等价物。）(TABLE c INTERSECT TABLE c is the equivalent of the first of the two statements just shown.)

与 UNION，操作数的列数必须相同。结果集列类型也如 UNION。As with UNION, the operands must have the same number of columns. Result set column types are also determined as for UNION.

INTERSECT 优先级高于，且在 UNION 和 EXCEPT，因此这里显示的两个语句是等价的：INTERSECT has greater precedence than and is evaluated before UNION and EXCEPT, so that the two statements shown here are equivalent:

TABLE r EXCEPT TABLE s INTERSECT TABLE t;

TABLE r EXCEPT (TABLE s INTERSECT TABLE t);

对于 INTERSECT ALL，左侧表格中任意唯一行的最大支持重复数为 4294967295。For INTERSECT ALL, the maximum supported number of duplicates of any unique row in the left hand table is 4294967295.