This database comparison study by Igor Valchenko analyzes storage efficiency between Firebird 5 and PostgreSQL 17 by creating identical tables with various data types (boolean, char, varchar, date, integer, numeric, float, time, timestamp) and populating them with one million rows each.

The research compares space utilization across different data types, revealing that PostgreSQL stores integer types more efficiently (81 MB versus 99.63 MB in Firebird), while Firebird demonstrates better efficiency with character data types, particularly for larger field sizes like CHAR(200) (2604.25 MB versus 2728 MB in PostgreSQL), and floating-point numbers.

The study's key findings emerge during update operations, where after updating 25% of all rows, PostgreSQL's database size increased to 9862 MB (a 25% growth), while Firebird showed more conservative growth to 8504 MB (only 8% increase), and after updating 50% of data, PostgreSQL required 26% additional space compared to Firebird's 21%, indicating that Firebird's multi-version concurrency control (MVCC) implementation is more space-efficient during frequent data modifications.