To query HBase tables using Hive, you first need to create a Hive external table that is mapped to an existing HBase table. This can be done using the following steps:

  1. Start the HBase Thrift Server: The HBase Thrift server is required to connect Hive to HBase. You can start the HBase Thrift server by running the following command: ./hbase thrift start.
  2. Start the Hive CLI: You can start the Hive CLI by running the following command: hive.
  3. Create a Hive External Table: Once you are in the Hive CLI, you can create an external table with the following command:

CREATE EXTERNAL TABLE <hive_table_name> (<column_name_1> <data_type_1>, ..., <column_name_n> <data_type_n>) STORED BY 'org.apache.hadoop.hive.hbase.HBaseStorageHandler' WITH SERDEPROPERTIES ("hbase.columns.mapping" = "<hbase_column_family_1>:<hbase_qualifier_1>,<hbase_column_family_2>:<hbase_qualifier_2>,...") TBLPROPERTIES("hbase.table.name" = "<hbase_table_name>");

Where:

  • <hive_table_name> is the name of the Hive external table.
  • <column_name_i> <data_type_i> are the columns and their data types in the Hive table.
  • <hbase_column_family_i> and <hbase_qualifier_i> are the HBase column family and qualifier, respectively, that corresponds to the Hive column <column_name_i>.
  • <hbase_table_name> is the name of the HBase table.
  1. Query the Hive External Table: You can now query the Hive external table as you would any other Hive table. The results of the query will be fetched from the underlying HBase table.

Note: It's important to keep in mind that while Hive provides a convenient way to query HBase tables, it does not provide the same level of performance as querying the HBase table directly. Additionally, not all Hive features are supported when querying HBase tables, so it's important to carefully consider your use case before using this approach.

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