Class WildcardSchemaProjection
java.lang.Object
org.apache.drill.exec.physical.impl.scan.project.ReaderLevelProjection
org.apache.drill.exec.physical.impl.scan.project.WildcardSchemaProjection
Perform a wildcard projection with an associated output schema.
Matches the reader schema against the output schema. If a column
appears, it is projected into the output schema. If not found,
then a null column (as defined by the output schema) is projected.
Note that we don't go down this path for strict schema: in that case we expanded the columns at the scan level.
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Nested Class Summary
Nested classes/interfaces inherited from class org.apache.drill.exec.physical.impl.scan.project.ReaderLevelProjection
ReaderLevelProjection.ReaderProjectionResolver
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Field Summary
Fields inherited from class org.apache.drill.exec.physical.impl.scan.project.ReaderLevelProjection
resolvers
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Constructor Summary
ConstructorDescriptionWildcardSchemaProjection
(ScanLevelProjection scanProj, TupleMetadata readerSchema, ResolvedTuple rootTuple, List<ReaderLevelProjection.ReaderProjectionResolver> resolvers) -
Method Summary
Methods inherited from class org.apache.drill.exec.physical.impl.scan.project.ReaderLevelProjection
resolveSpecial
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Constructor Details
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WildcardSchemaProjection
public WildcardSchemaProjection(ScanLevelProjection scanProj, TupleMetadata readerSchema, ResolvedTuple rootTuple, List<ReaderLevelProjection.ReaderProjectionResolver> resolvers)
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