Yes: it is the relatively new approach by Cahill et al in 2008, known as SSI: https://courses.cs.washington.edu/courses/cse444/08au/544M/READING-LIST/fekete-sig

Yes: it is the relatively new approach by Cahill et al in 2008, known as SSI: https://courses.cs.washington.edu/courses/cse444/08au/544M/READING-LIST/fekete-sigmod2008.pdf https://courses.cs.washington.edu/courses/cse444/08au/544M/R... Which, as far as production-common database implementations go, is lightspeed for implementing new academic work (9.1, the first version with the feature, was released in 2011).