and may be pass-by- value (the value itself, for types like integer), or pass-by- reference, for arbitrary sized types like jsonb. • Before, text was always simply treated as pass-by- reference. Pointer chasing required for every comparison. • However, with new abbreviated keys, a special pass-by- value prefix is stored rather than a pointer. Usually sufficient to resolve comparison without pointer chasing. • Basically, abbreviated value is first 8 bytes of each string being sorted.