FromParquet
Factory of builders of Parquet readers.
Attributes
- Graph
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- Supertypes
Members list
Value members
Abstract methods
Creates Builder of Parquet reader for projected documents of type T. Due to projection reader does not attempt to read all existing columns of the file but applies enforced projection schema.
Creates Builder of Parquet reader for projected documents of type T. Due to projection reader does not attempt to read all existing columns of the file but applies enforced projection schema.
Attributes
Creates Builder of Parquet reader of projected generic records. Due to projection reader does not attempt to read all existing columns of the file but applies enforced projection schema.
Creates Builder of Parquet reader of projected generic records. Due to projection reader does not attempt to read all existing columns of the file but applies enforced projection schema.
Attributes
Creates Builder of Parquet reader returning projected generic records. Due to projection, reader does not attempt to read all existing columns of the file but applies enforced projection schema. Besides simple projection one can use aliases and extract values from nested fields - in a way similar to SQL.
Creates Builder of Parquet reader returning projected generic records. Due to projection, reader does not attempt to read all existing columns of the file but applies enforced projection schema. Besides simple projection one can use aliases and extract values from nested fields - in a way similar to SQL.
Value parameters
- col
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first column projection
- cols
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next column projections
Attributes
- Example
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projectedGeneric( Col("foo").as[Int], // selects Int column "foo" Col("bar.baz".as[String]), // selects String field "bar.baz", creates column "baz" wih a value of "baz" Col("bar.baz".as[String].alias("bar_baz")) // selects String field "bar.baz", creates column "bar_baz" wih a value of "baz" )