ClickHouse/docs/en/sql-reference/statements/select/intersect.md

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---
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)
2021-10-22 08:58:34 +00:00
- [EXCEPT](except.md#except-clause)