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Module nullable

Module nullable 

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Nullable column type (Nullable(T)). Nullable column implementation

ClickHouse Documentation: https://clickhouse.com/docs/en/sql-reference/data-types/nullable

§Important Nesting Restrictions

ClickHouse does NOT allow wrapping certain types in Nullable:

  • Nullable(Array(...)) - NOT allowed (Error code 43)
  • Nullable(LowCardinality(...)) - NOT allowed

Correct usage:

  • Array(Nullable(...)) - Nullable elements inside array
  • LowCardinality(Nullable(...)) - Nullable values with dictionary encoding

See: https://github.com/ClickHouse/ClickHouse/issues/1062

Structs§

ColumnNullable
Column for nullable values
ColumnNullableT
Typed nullable column wrapper (matches C++ ColumnNullableT)