Add way to disables statistics on a per column basis
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Descripción
When you write dataset with BINARY columns that can be fairly large (several Mbs) you can often end with an OutOfMemory error where you either have to:
- Throw more RAM
- Increase number of output files
- Play with Block size
Using a fork with increased checks frequency for row group size help but it is not enough. (PR: )
The OutOfMemory error is now caused due to the accumulation of min/max values for those columns for each BlockMetaData.
The "parquet.statistics.truncate.length" configuration is of no help because it is applied during the footer serialization whereas the OOM occurs before that.
I think it would be nice to have, like for dictionary or bloom filter, a way to disable the statistic on a per-column basis.
Could be very useful to lower memory consumption when stats of huge binary column are unnecessary.
**Reporter**: [Anthony Pessy](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=panthony) / @panthony
#### Original Issue Attachments:
- [add_config_to_opt-out_of_a_column's_statistics.patch](https://issues.apache.org/jira/secure/attachment/13011473/add_config_to_opt-out_of_a_column%27s_statistics.patch)
- [NoOpStatistics.java](https://issues.apache.org/jira/secure/attachment/13037932/NoOpStatistics.java)
**Note**: *This issue was originally created as [PARQUET-1911](https://issues.apache.org/jira/browse/PARQUET-1911). Please see the [migration documentation](https://issues.apache.org/jira/browse/PARQUET-2502) for further details.*
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Línea de trabajo
Comienza leyendo los archivos adjuntos NoOpStatistics.java y add_config_to_opt-out_of_a_column's_statistics.patch; después, sigue cómo se acumulan las estadísticas en BlockMetaData antes de la serialización del footer. Se considera terminado cuando se proporcione una forma de deshabilitar las estadísticas por columna, de modo que las columnas BINARY grandes dejen de acumular valores min/max y provocar errores OutOfMemory.
Escrito por el modelo de indexación a partir del texto del issue.
Evaluación
- Stack tecnológico
- java
- Área
- data-engineering
- Tipo de issue
- Nueva funcionalidad
- Dificultad
- 4/5
- Tiempo estimado
- 3-5 días
- Estado de actividad
- Estancado
- Claridad
- Bastante claro
- Aptitud para principiantes
- 35/100