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add map to list of unsupported nullable types
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@ -8,7 +8,7 @@ sidebar_label: Nullable
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Allows to store special marker ([NULL](../../sql-reference/syntax.md)) that denotes “missing value” alongside normal values allowed by `TypeName`. For example, a `Nullable(Int8)` type column can store `Int8` type values, and the rows that do not have a value will store `NULL`.
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Allows to store special marker ([NULL](../../sql-reference/syntax.md)) that denotes “missing value” alongside normal values allowed by `TypeName`. For example, a `Nullable(Int8)` type column can store `Int8` type values, and the rows that do not have a value will store `NULL`.
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For a `TypeName`, you can’t use composite data types [Array](../../sql-reference/data-types/array.md) and [Tuple](../../sql-reference/data-types/tuple.md). Composite data types can contain `Nullable` type values, such as `Array(Nullable(Int8))`.
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For a `TypeName`, you can’t use composite data types [Array](../../sql-reference/data-types/array.md), [Map](../../sql-reference/data-types/map.md) and [Tuple](../../sql-reference/data-types/tuple.md). Composite data types can contain `Nullable` type values, such as `Array(Nullable(Int8))`.
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A `Nullable` type field can’t be included in table indexes.
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A `Nullable` type field can’t be included in table indexes.
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