HammerDB vs pgroll

HammerDB is a free database benchmarking application for running workloads across SQL Server, Db2, Oracle, PostgreSQL, MariaDB, MySQL and VillageSQL. It offers graphical, command-line, web and automation interfaces, with Windows and Linux builds, a Docker image and on-premise deployment. Version 6.0 adds CI and pipeline capabilities for MariaDB, MySQL and PostgreSQL, covering schema sizing, workload execution and result capture. It reports I/O measures such as IOPS and MB/s and provides Active Session History viewers for MySQL and MariaDB. Timing profiles use reservoir sampling and extended percentile reporting to compare response-time distributions. Users can upload benchmark artifacts containing workload results, database versions, metrics and system metadata. The web service can run as an SCGI application behind a web server or automation gateway. HammerDB is released under the GNU General Public License Version 3. Automated workflows may require compilers, database dependencies, libraries and operating-system tools.

pgroll is an open-source command-line tool for PostgreSQL schema migrations that keeps old and new schema versions available while applications move between them. Its expand/contract workflow lets clients choose a version through PostgreSQL's search_path. The project describes migrations as zero-downtime and says it applies changes without locking the database; it can also backfill columns automatically when needed. For breaking changes, pgroll builds virtual schemas from views over physical tables and uses triggers to carry writes between old and new columns. Active migrations can be rolled back to the previous schema version. It supports PostgreSQL 14 and later, including RDS and Aurora, and is available for Linux, macOS, and Windows or self-hosting. It can convert SQL generated by ORMs, with examples for Alembic, Django, and Drizzle, though manual data migrations and SQL consolidation may be needed. On PostgreSQL 14, its versioned views do not respect row-level security policies, which can make it a poor choice for RLS users on that version. The project is licensed under Apache License 2.0.