Synopse

Our downloadable documentation has been enhanced, and contains now a description about the main feature of the near-to-come 1.15 version, i.e. "database agnosticism".

The core database of our mORMot / SQLite3 framework uses the SQLite3 library, which is a Free, Secure, Zero-Configuration, Server-less, Single Stable Cross-Platform Database File database engine.

As stated below, you can use any other database access layer, if you wish. A fast in-memory engine is included, and can be used instead or together with the SQLite3 engine. Since revision 1.15 of the framework you may be able to access any remote database, and use one or more OleDB (or Oracle) connections to store your precious ORM objects. The SQlite3 will be used as the main SQL engine, able to JOIN all those tables, thanks to its Virtual Table unique feature.

This is a major step for the framework.

Among a lot of new features and bug fixes:

• Dynamic arrays and Record handling, including low-level access and high-level handling for the ORM part of the framework (using TDynArray wrapper);
• Business rules now handled via filtering and validating classes for both our ORM and the Synopse Big Table;
• New full-featured logging classes, with exception handling, stack trace and JSON serialization;
• Custom SQL functions and TSQLRecordRTree to implement R-Tree virtual tables;
• Batch sequences for adding/updating/deleting multiple records;
• Secure RESTful authentication via per-user light sessions, and per-query signature;
• Define custom Virtual Tables (i.e. access any kind of data from SQL) in Delphi code;
• New HTTP server using fast http.sys kernel-mode server and zip / SynLZ compression;
• SynTaskDialog unit native under Vista,Seven with emulation code under XP/2000 ;
• User Interface automated Generation using standard VCL or proprietary TMS components;
• Documentation completed - more than 600 pages by now, including general User Guide and exhaustive Technical Reference;
• Updated SQLite3 database engine to version 3.7.6.3;
• Numerous bug fixes, speed and feature enhancements (including in the PDF and other UI-related units).

Open Source project, for Delphi 6 up to XE, licensed under a MPL/LGPL/GPL tri-license.

The SQlite3 engine has ability to create Virtual Tables from code. From the perspective of an SQL statement, the virtual table object looks like any other table or view. But behind the scenes, queries from and updates to a virtual table invoke callback methods on the virtual table object instead of reading and writing to the database file.

The virtual table mechanism allows an application to publish interfaces that are accessible from SQL statements as if they were tables. SQL statements can in general do anything to a virtual table that they can do to a real table, with the following exceptions:
- One cannot create a trigger on a virtual table.
- One cannot create additional indices on a virtual table. (Virtual tables can have indices but that must be built into the virtual table implementation. Indices cannot be added separately using CREATE INDEX statements.)
- One cannot run ALTER TABLE ... ADD COLUMN commands against a virtual table.
- Particular virtual table implementations might impose additional constraints. For example, some virtual implementations might provide read-only tables. Or some virtual table implementations might allow INSERT or DELETE but not UPDATE. Or some virtual table implementations might limit the kinds of UPDATEs that can be made.

Example of virtual tables, already included in the SQLite3 engine, are FTS or RTREE tables. A custom virtual table might represent in-memory data structures (like TSQLVirtualTableJSON, TSQLVirtualTableBinary). Or it might represent a view of data on disk that is not in the SQLite3 format (e.g. TSQLVirtualTableLog). Or the application might compute the content of the virtual table on demand.

Thanks to the generic implementation of Virtual Table in SQLite3, you can use such tables in your SQL statement, and even safely execute a SELECT statement with JOIN or custom functions, mixing normal SQLite3 tables and any other Virtual Table.

A dedicated mechanism has been added to the framework, beginning with revision 1.13, in order to easily add such virtual tables with pure Delphi code, just by inheriting some classes.