5 ;;Quote: in database programming, data persists after the program; distinguishes database programming languages

5 ;;Quote: associate persistence with values and separate type from extent; e.g., the integer extent is almost useless; may want multiple extents

6 ;;Quote: in database design, the instance hierarchy may depend on an attribute; e.g., inexpensive products may be treated as bulk items

6 ;;Quote: is class (i.e., type + extent) a parameterized data type like 'array of int'?

11 ;;Quote: any value should be able to persist; PS-algol was the first practical, persistent language

12 ;;Quote: persistence is a property of values not types

12+;;Quote: while a value persists, so should its description (type); avoids round-trip errors

12 ;;Quote: all-or-nothing persistence saves the state of an interactive session; unstructured, cannot share values, includes volatile structures, depends on programming system

12 ;;Quote: replicating persistence uses instructions to move structures in and out of secondary storage; e.g., files, APL

12+;;Quote: APL stores values as arrays; flat, simple data structures

12 ;;Quote: as persistent storage, files cannot contain pointers nor carry their own types

12 ;;Quote: concurrent use of replicating persistence requires synchronized extern and intern operations

12 ;;Quote: with intrinsic persistence, all values persist as needed; no replicating of data; no distinction between primary and secondary storage

13 ;;Quote: a commit instruction is needed for intrinsic persistence; otherwise program failure may lead to an inconsistent database