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70 lines
1.7 KiB
Markdown
70 lines
1.7 KiB
Markdown
---
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toc_title: EXCEPT
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---
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# EXCEPT Clause {#except-clause}
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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.
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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.
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``` sql
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SELECT column1 [, column2 ]
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FROM table1
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[WHERE condition]
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EXCEPT
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SELECT column1 [, column2 ]
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FROM table2
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[WHERE condition]
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```
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The condition could be any expression based on your requirements.
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**Examples**
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Query:
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``` sql
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SELECT number FROM numbers(1,10) EXCEPT SELECT number FROM numbers(3,6);
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```
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Result:
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``` text
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┌─number─┐
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│ 1 │
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│ 2 │
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│ 9 │
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│ 10 │
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└────────┘
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```
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Query:
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``` sql
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CREATE TABLE t1(one String, two String, three String) ENGINE=Memory();
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CREATE TABLE t2(four String, five String, six String) ENGINE=Memory();
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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');
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INSERT INTO t2 VALUES ('q', 'm', 'b'), ('b', 'd', 'k'), ('s', 'y', 't'), ('s', 'd', 'f'), ('m', 'f', 'o'), ('k', 'k', 'd');
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SELECT * FROM t1 EXCEPT SELECT * FROM t2;
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```
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Result:
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``` text
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┌─one─┬─two─┬─three─┐
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│ l │ p │ o │
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│ k │ t │ d │
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│ l │ p │ o │
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└─────┴─────┴───────┘
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```
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**See Also**
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- [UNION](union.md#union-clause)
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- [INTERSECT](intersect.md#intersect-clause)
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