Fix performance regression when hive SerDe doesn't prefer Writables #5142
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Introduced in prestodb#8206, GenericHiveRecordCursor was modified to avoid extra overhead when the SerDe provided a more efficient String handling implementation with Writables. However, when the SerDe does not provide such an implementation and instead already returned String instances directly, this change introduced an extra conversion from bytes to String just to be converted back to bytes. This change alters the behavior of GenericHiveRecordCursor parseString to respect the PrimitiveObjectInspector's preference for using writables.
electrum
approved these changes
Sep 11, 2020
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Cross contribution of prestodb/presto#15163
Introduced in prestodb/presto#8206
GenericHiveRecordCursorwas modified to avoid extra overhead when the SerDe provided a more efficient String handling implementation with Writables. However, when the SerDe does not provide such an implementation and instead already returned String instances directly, this change introduced an extra conversion from bytes to String just to be converted back to bytes.This change alters the behavior of
GenericHiveRecordCursor#parseStringto respect the PrimitiveObjectInspector's preference for using writables.