Product comparison chart

Polyhedra product comparison chart

The table below gives a brief summary of the main features of Polyhedra, with an indication of whether the feature is available in a particular edition of Polyhedra. (Note: in some cases support for a feature by a particular edition of Polyhedra is 'modular': it can be omitted from the executables if not used, to reduce the code footprint - or, for some editions, it may be omitted from the supplied executables, and these would have to be relinked to enable the feature.)
 
Feature
Polyhedra 64 IMDB Polyhedra 32 IMDB Polyhedra Lite Polyhedra Flash DBMS
SQL relational database, supporting views; INSERT, UPDATE, DELETE; queries with joins; foreign keys yes yes yes yes
Dynamic table creation, alteration and deletion yes yes yes yes
Strict enforcement of entity (data types) and referential integrity yes yes yes yes
● 64-bit, 32-bit, 16-bit and 8-bit signed integers
● 64-bit and 32-bit floating point values
● bounded and unbounded character strings (+ UNICODE option)
● unbounded binary objects
● datetime
● Booleans
yes yes yes yes
Table inheritance; 'shared' and 'virtual' attributes yes yes yes yes
Ability to mark tables and columns as persistent or transient yes yes yes yes
Ordered and hash indexes yes yes yes yes
Client-server architecture, keeping data separate from the applications that use it (and thus safer) yes yes yes yes
Standards-conformant ODBC and JDBC client libraries yes yes yes yes
Cross platform support yes yes yes yes
interworking with older releases yes yes yes yes
interworking with other Polyhedra products yes yes no yes
Address mode (which affects the platforms supported, and the size of database supported by Polyhedra IMDB) 64-bit 32-bit 32-bit 32-bit
Maximum database size determined by the memory available to a single process 2 GB
Platform-independent database files yes yes yes yes
Fully transactional, with ACID operation yes yes yes yes
Provision for snapshots, for offline storage and analysis yes yes yes yes
Mechanisms for data durability Snapshots plus journal logging Shadow paging
Support for High Availability configurations yes yes no yes
Support for read-only replica servers yes yes no no
Subscriptions: allow a database to have an active cache of data from another yes yes no no
Active queries, with clients automatically updated yes yes yes yes
Interface to PLCs, RTUs (‘the DVI module’) yes yes no no
Historian module, to store and retrieve time-series data yes yes no no
Where is the master copy of the data stored? RAM RAM RAM file
Configurable RAM cache n/a n/a n/a yes
Configurable limit on total file size n/a n/a n/a yes
Configurable limits on size of individual tables no no no yes
Configurable limits on total RAM usage yes yes yes yes
Configurable limit on space used on behalf of a client yes yes yes yes
Debugging module yes yes no yes