mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-02 20:42:04 +00:00
74 lines
1.7 KiB
Markdown
74 lines
1.7 KiB
Markdown
---
|
|
toc_title: INTERSECT
|
|
---
|
|
|
|
# INTERSECT Clause {#intersect-clause}
|
|
|
|
The `INTERSECT` clause returns only those rows that result from both the first and the second queries. The queries must match the number of columns, order, and type. The result of `INTERSECT` can contain duplicate rows.
|
|
|
|
Multiple `INTERSECT` statements are executes left to right if parenthesis are not specified. The `INTERSECT` operator has a higher priority than the `UNION` and `EXCEPT` clause.
|
|
|
|
|
|
``` sql
|
|
SELECT column1 [, column2 ]
|
|
FROM table1
|
|
[WHERE condition]
|
|
|
|
INTERSECT
|
|
|
|
SELECT column1 [, column2 ]
|
|
FROM table2
|
|
[WHERE condition]
|
|
|
|
```
|
|
The condition could be any expression based on your requirements.
|
|
|
|
**Examples**
|
|
|
|
Query:
|
|
|
|
``` sql
|
|
SELECT number FROM numbers(1,10) INTERSECT SELECT number FROM numbers(3,6);
|
|
```
|
|
|
|
Result:
|
|
|
|
``` text
|
|
┌─number─┐
|
|
│ 3 │
|
|
│ 4 │
|
|
│ 5 │
|
|
│ 6 │
|
|
│ 7 │
|
|
│ 8 │
|
|
└────────┘
|
|
```
|
|
|
|
Query:
|
|
|
|
``` sql
|
|
CREATE TABLE t1(one String, two String, three String) ENGINE=Memory();
|
|
CREATE TABLE t2(four String, five String, six String) ENGINE=Memory();
|
|
|
|
INSERT INTO t1 VALUES ('q', 'm', 'b'), ('s', 'd', 'f'), ('l', 'p', 'o'), ('s', 'd', 'f'), ('s', 'd', 'f'), ('k', 't', 'd'), ('l', 'p', 'o');
|
|
INSERT INTO t2 VALUES ('q', 'm', 'b'), ('b', 'd', 'k'), ('s', 'y', 't'), ('s', 'd', 'f'), ('m', 'f', 'o'), ('k', 'k', 'd');
|
|
|
|
SELECT * FROM t1 INTERSECT SELECT * FROM t2;
|
|
```
|
|
|
|
Result:
|
|
|
|
``` text
|
|
┌─one─┬─two─┬─three─┐
|
|
│ q │ m │ b │
|
|
│ s │ d │ f │
|
|
│ s │ d │ f │
|
|
│ s │ d │ f │
|
|
└─────┴─────┴───────┘
|
|
```
|
|
|
|
**See Also**
|
|
|
|
- [UNION](union.md#union-clause)
|
|
- [EXCEPT](except.md#except-clause)
|