Apache Drill vs Apache Impala

Apache Drill is a schema-free SQL query engine for Hadoop, NoSQL databases, and cloud storage. It can query raw data where it resides without first loading it, defining schemas, or transforming it. Its JSON data model supports complex and nested structures, and a single query can join data across multiple datastores. Listed sources include HBase, MongoDB, HDFS, Amazon S3, Azure Blob Storage, Google Cloud Storage, Swift, NAS, and local files. JDBC and ODBC drivers connect Drill to tools including Tableau, Qlik, MicroStrategy, Spotfire, SAS, and Excel; developers can also use its REST API in custom applications. Drill can run embedded on a laptop or in distributed mode on a server cluster, and the homepage lists Mac, Windows, and Linux. Documented security options include Kerberos, username and password authentication, Digest, authorization, and impersonation. The software is free under Apache License 2.0. A compatibility limit: official support for Hadoop 2 and Java 8 was dropped with Drill 1.22.0.

Apache Impala is a free, open-source native analytic database for SQL queries on open data and table formats. It targets low-latency, high-concurrency business intelligence and analytics in Hadoop environments and is described as scaling linearly, including for multitenant use. Impala works with HDFS, HBase and Amazon S3, plus Apache Kudu, Apache Iceberg and other listed sources. Supported formats include delimited text, Parquet, Avro, SequenceFile and RCFile, with Snappy, GZIP, Deflate and BZIP codecs. Clients can connect through impala-shell, Hue, JDBC or ODBC. The system reuses Hadoop file formats, metadata, security and resource-management frameworks, and shares metadata and an ODBC driver with Apache Hive. Kudu tables support queries and efficient updates or deletes; Iceberg tables can be registered with the Hive Metastore. Kerberos, Apache Ranger authorization, auditing and encrypted JDBC or ODBC connections are supported. Impala runs on Linux and macOS, supports API use and self-hosted deployment, and is licensed under Apache License 2.0.