Hola, Habr. Para los futuros alumnos del curso "Ecosistema Hadoop, Spark, Hive" se preparó una traducción del material.
También invitamos a todos al seminario web "Prueba de aplicaciones Spark" . En esta lección abierta, consideraremos los problemas al probar aplicaciones Spark: datos estadísticos, verificación parcial y arranque / parada de sistemas pesados. Estudiemos las bibliotecas para la solución y escribamos pruebas.
Este artículo se centra exclusivamente en la operación Join en Apache Spark y proporciona una descripción general de la base sobre la que se construye la tecnología Spark Join.
Las uniones se utilizan a menudo en flujos de minería de datos típicos para correlacionar dos conjuntos de datos. Apache Spark, al ser un motor de análisis unificado, también ha proporcionado una base sólida para ejecutar una amplia variedad de escenarios de combinación.
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