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fixes for data_types/special_data_types/nothing.md

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Ivan Blinkov 2018-09-06 19:35:14 +03:00
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docs/en/data_types/special_data_types/nothing.md
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# Nothing
The only purpose of this data type is to represent [NULL](../../query_language/syntax.md#null-literal), i.e., no value.
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.
You can't create a `Nothing` type value, because it is used where a value is not expected. For example, `NULL` is written as `Nullable(Nothing)` ([Nullable](../../data_types/nullable.md#data_type-nullable) is the data type that allows storing `NULL` in tables).
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).
The `Nothing` type is also used to denote empty arrays:
The `Nothing` type can also used to denote empty arrays:
```bash
:) SELECT toTypeName(Array())
:) SELECT toTypeName(array())
SELECT toTypeName([])