ClickHouse/docs/en/sql-reference/statements/select/except.md
2022-08-28 10:53:34 -04:00

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---
slug: /en/sql-reference/statements/select/except
sidebar_label: EXCEPT
---
# EXCEPT Clause
The `EXCEPT` clause returns only those rows that result from the first query without the second. The queries must match the number of columns, order, and type. The result of `EXCEPT` can contain duplicate rows.
Multiple `EXCEPT` statements are executed left to right if parenthesis are not specified. The `EXCEPT` operator has the same priority as the `UNION` clause and lower priority than the `INTERSECT` clause.
``` sql
SELECT column1 [, column2 ]
FROM table1
[WHERE condition]
EXCEPT
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) EXCEPT SELECT number FROM numbers(3,6);
```
Result:
``` text
┌─number─┐
│ 1 │
│ 2 │
│ 9 │
│ 10 │
└────────┘
```
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 EXCEPT SELECT * FROM t2;
```
Result:
``` text
┌─one─┬─two─┬─three─┐
│ l │ p │ o │
│ k │ t │ d │
│ l │ p │ o │
└─────┴─────┴───────┘
```
**See Also**
- [UNION](union.md#union-clause)
- [INTERSECT](intersect.md#intersect-clause)