Understanding Bigfile Tablespace Defaults in Oracle Database 23ai: Impact and Benefits

Oracle Database 23ai introduces a significant but subtle shift in its default storage architecture, the adoption of bigfile tablespaces as the default for most tablespaces, including core ones like SYSTEM and SYSAUX. This change reflects Oracle’s continued evolution towards simplifying storage management and scaling capabilities. As database professionals with years of experience managing complex environments, understanding this new default and its impact on performance and administration is critical. Background: What Are Bigfile Tablespaces? Bigfile tablespaces were originally introduced in Oracle 10g as a means to address scalability challenges in very large databases. Unlike traditional small-file tablespaces, which consist of multiple datafiles each limited in size (typically up to 32 GB or 128 GB, depending on block size and OS), a bigfile tablespace consists of a single large datafile that can grow up to 128 terabytes (TB) or more, depending on the platform and block size.