Apache Tajo supports the custom / user defined functions (UDFs). The custom functions can be created in python. The custom functions are just plain python functions with decorator “@output_type(<tajo sql datatype>)” as…
Apache Tajo provides JDBC interface to connect and execute queries. We can use the same JDBC interface to connect Tajo from our Java based application. Let us now understand how…
Swift is a distributed and consistent object/blob store. Swift offers cloud storage software so that you can store and retrieve lots of data with a simple API. Tajo supports Swift…
Tajo supports the HiveCatalogStore to integrate with Apache Hive. This integration allows Tajo to access tables in Apache Hive. Set Environment Variable Add the following changes to “conf/tajo-env.sh” file. $…
Apache Tajo supports HBase integration. This enables us to access HBase tables in Tajo. HBase is a distributed column-oriented database built on top of the Hadoop file system. It is…
Tajo supports various storage formats. To register storage plugin configuration, you should add the changes to the configuration file “storage-site.json”. storage-site.json The structure is defined as follows − { "storages":…
This chapter explains about the following significant Queries. PredicatesExplainJoin Let us proceed and perform the queries. Predicates Predicate is an expression which is used to evaluate true/false values and UNKNOWN.…
This chapter explains the aggregate and window functions in detail. Aggregation Functions Aggregate functions produce a single result from a set of input values. The following table describes the list…
In the previous chapter, you have understood how to create tables in Tajo. This chapter explains about the SQL statement in Tajo. Create Table Statement Before moving to create a…
A table is a logical view of one data source. It consists of a logical schema, partitions, URL, and various properties. A Tajo table can be a directory in HDFS,…