ODB is a compiler-based object-relational mapping (ORM) system for C++. It allows you to persist C++ objects to a relational database without having to deal with tables, columns, or SQL and without manually writing any mapping code. The C++ code that performs the conversion between persistent classes and their database representation is automatically generated by the ODB compiler. The ODB compiler is a real C++ compiler except that instead of producing assembly or machine code, it generates portable C++, which can in turn be compiled by any C++ compiler. ODB is not a framework. It does not dictate how you should write your application. Rather, it is designed to fit into your style and architecture by only handling C++ object persistence and not interfering with any other functionality.
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Major new features in this release include multi-database support, prepared queries, change-tracking containers, custom sessions, and automatic mapping for char[N]. This version also adds support for Qt5 in addition to Qt4, and comes with a guide on using ODB with mobile/embedded systems.
Major new features in this release are support for the Microsoft SQL Server database, including updates to the Boost and Qt profiles, support for database schemas (database namespaces), and the ability to define composite value types as C++ class template instantiations.
Major new features in this release are support for the Oracle database, including updates to the Boost and Qt profiles, support for optimistic concurrency using object versioning, support for read-only/const data members, support for persistent classes without object ids, and support for SQL statement execution tracing.
The major new feature in this release is the introduction of the view concept. A view is a read-only projection of one or more persistent objects or database tables or the result of a native SQL query execution. Other important features in this release include support for deleting persistent objects using a query expression, support for the NULL semantics with mapping to smart pointers, odb::nullable, or boost::optional, and support for mapping BLOB types to std::vector<char>.
Major new features in this release are support for PostgreSQL, including updates to the Boost and Qt profiles, support for per-class database operations callbacks, a new NULL handling mechanism, as well as the ability to specify database default values and additional column definition options.