PostgreSQL 排序相同值不固定的问题

Imagine a world where reality itself is fluid, shifting its foundations with every passing moment. This is the experience of querying PostgreSQL when dealing with duplicate sort values. Unlike SQL Server, which meticulously arranges data like books on a perfectly organized shelf, PostgreSQL operates with the chaotic elegance of a drawer that fills whatever empty space is available at any given instant. When multiple records share the exact same creation timestamp, their physical location in memory is not fixed but transient, dictated by the whims of vacuum processes and storage allocation. Consequently, two identical queries executed milliseconds apart may return results in completely different orders, not because the data has changed, but because the underlying architecture refuses to guarantee stability for indistinguishable elements. This phenomenon challenges our fundamental assumption that order implies permanence. If the database engine does not care about the relative position o...--AI Generated