Top Key Architecture Components in HIVE
5 architectural components present in Hadoop Hive: Shell: allows interactive queries like MySQL shell connected to a database – Also supports web and JDBC clients Driver: session handles, fetch, execute Compiler: parse, plan, optimize Execution engine: DAG of stages (M/R, HDFS, or metadata) Metastore: schema, location in HDFS, SerDe Data Mode of Hive: Tables – Typed columns (int, float, string, date, boolean) – Also, list: map (for JSON-like data) Partitions – e.g., to range-partition tables by date Buckets – Hash partitions within ranges (useful for sampling, join optimization) HIVE Meta Store Database: namespace containing a set of tables Holds table definitions (column types, physical layout) Partition data Uses JPOX ORM for implementation; can be stored in Derby, MySQL, many other relational databases Physical Layout of HIVE Warehouse directory in HDFS – e.g., /home/hive/warehouse Tables stored in subdirectories of warehouse – Partitions, buckets