1.8. MEMORY for Memory-Only Databases
Interchange's memory-based databases are the fastest possible way to organize and store frequently used data. To force a database to be built in memory instead of DBM, use the MEMORY modifier:
Database country country.asc TAB Database country MEMORY 1
Obviously, large tables will use a great deal of memory, and the data will need to be re-imported from the ASCII source file at every catalog reconfiguration or Interchange restart. The big advantage of using MEMORY is that the database remains open at all times and does not need to be reinitialized at every connect. Use it for smaller tables that will be frequently accessed.
Memory tables are read only -- the MEMORY modifier forces IMPORT_ONCE.