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25 lines
764 B
Markdown
25 lines
764 B
Markdown
<a name="special_data_type-nothing"></a>
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# Nothing
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The only purpose of this data type is to represent cases where value is not expected. So you can't create a `Nothing` type value.
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For example, literal [NULL](../../query_language/syntax.md#null-literal) has type of `Nullable(Nothing)`. See more about [Nullable](../../data_types/nullable.md#data_type-nullable).
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The `Nothing` type can also used to denote empty arrays:
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```bash
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:) SELECT toTypeName(array())
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SELECT toTypeName([])
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┌─toTypeName(array())─┐
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│ Array(Nothing) │
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└─────────────────────┘
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1 rows in set. Elapsed: 0.062 sec.
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```
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[Original article](https://clickhouse.yandex/docs/en/data_types/special_data_types/nothing/) <!--hide-->
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