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Version 1.6.0
* SQLite ODB runtime now enabled foreign key constraints checking by
default. While this should not affect correct applications, due to
bugs in SQLite DDL foreign keys support, you may need to temporarily
disable foreign key constraints checking when re-creating the database
schema (the sign that you may need to do so is the "foreign key
constraint failed" exception thrown by the commit() function after the
call to schema_catalog::create_schema()). For more information, refer
to Section 12.5.3, "Foreign Key Constraints" in the ODB manual.
* New function, database::erase_query(), allows the deletion of the
database state of multiple objects matching certain criteria. It uses
the same query expression as the database::query() function. For more
information, refer to Section 3.10, "Deleting Persistent Objects" in
the ODB manual.
* Support for value wrappers. An ODB value wrapper is a class template
that wraps a value type. Common examples of wrappers are smart pointers,
holders, and "optional value" containers such as boost::optional. A
wrapper can be transparent or it can handle the NULL semantics. To
allow the easy conversion of value types that do not support the NULL
semantics into the ones that do, the odb::nullable class template has
been added. ODB also now includes built-in support for std::auto_ptr
and std::tr1::shared_ptr smart pointers as value wrappers as well as
for boost::shared_ptr and QSharedPointer via the Boost and Qt profiles.
For more information, refer to Section 7.3, "NULL Value Semantics" in
the ODB manual.
* Support for the boost::optional container in the Boost profile. A data
member of the boost::optional type is mapped to a column that can have
a NULL value. For more information, refer to Section 15.3 "Optional
Library" in the ODB manual.
* Support for mapping std::vector<char> to the BLOB (or equivalent) types.
For more information, refer to chapters 11 (for MySQL), 12 (for SQLite)
and 13 (for PostgreSQL) in the ODB manual.
* New option, --table-prefix, allows the specification of a prefix that
is added to table and index names. For more information, refer to the
ODB compiler command line interface documentation (man pages).
* New ODB runtime interface, odb::connection, represents a connection
to the database. The primary use case for a connection is to execute
native statements outside of a transaction. For more information, refer
to Section 3.5, "Connections" in the ODB manual.
Version 1.5.0
* Support for the PostgreSQL database. The provided connection factories
include 'new' (a new connection is created every time one is requested)
and 'pool' (a pool of connections is maintained). The Boost and Qt
profiles have been updated to support this database. For more information,
refer to Chapter 13, "PostgreSQL Database" in the ODB manual.
* New handling of the NULL semantics. Now, instead of being specified as
part of the SQL type with the type pragma, there are separate null and
not_null pragmas. The not_null pragma was used to control the NULL
semantics of object pointers. Now the two pragmas are used consistently
for object pointers and simple values (and, in the future, they will work
for composite values and containers). To control the NULL semantics of
the container's element values, the value_null and value_not_null pragmas
have been added, similar to the value_type, value_column, etc., pragmas.
For more information about the new mechanism, refer to Sections 10.2.3,
10.2.8, 10.3.4, and 10.3.13 in the ODB manual.
This is a backwards-incompatible change. Existing use cases that will
require manual changes are listed below.
For pragmas that apply to simple value types and data members of
such types:
#pragma db type("TEXT NOT NULL") => #pragma db type("TEXT")
#pragma db type("TEXT NULL") => #pragma db type("TEXT") null
#pragma db type("TEXT") => #pragma db type("TEXT") null
For pragmas that apply to containers of pointers and data members of
such types:
#pragma db not_null => #pragma db value_not_null
* New pragma, default, allows the specification of the database default
value. For more information, refer to Section 10.3.5, "default" in the
ODB manual.
* New pragmas, options, id_options, index_options, key_options, and
value_options, allow the specification of additional column definition
options. For more information, refer to Section 10.3.6, "options" in
the ODB manual.
* Support for database operations callbacks. Now a persistent class can
register a callback function that will be called before and after every
database operation (such as persist, load, update, or erase) is performed
on an object of this class. A database operations callback can be used to
implement object-specific pre and post initializations, registrations,
and cleanups. For more information and an example, refer to Section
10.1.4, "callback" in the ODB manual.
* New option, --include-regex, allows the modification of the #include
directive paths generated by the ODB compiler. This is primarily useful
when placing the generated code into subdirectories and the #include
directives have to be adjusted accordingly. The --include-regex-trace
option is useful for debugging the expressions specified with
--include-regex.
Version 1.4.0
* New profile, qt, provides persistence support for the Qt framework. This
version covers the most commonly used basic types, date-time types, smart
pointers, and containers. The qt profile implementation is provided by the
libodb-qt library. For more information refer to Chapter 13, "Profiles
Introduction" and Chapter 15, "Qt Profile" in the ODB manual as well as
the 'qt' example in the odb-examples package.
* Support for non-polymorphic object inheritance, including the new abstract
pragma. For more information refer to Chapter 8, "Inheritance" in the ODB
manual as well as the 'inheritance' example in the odb-examples package.
* Automatic mapping of C++ enumerations to suitable database types. In
database systems that support enumeration types (such as MySQL), a C++
enum is mapped to such a type (for example, ENUM('red', 'green', 'blue')
in MySQL). Otherwise, it is mapped to a suitable integer type. Refer to
Part II, "Database Systems" in the ODB manual for more details on the
provided mappings.
* New pragma, id_type, allows the specification of the native database type
that should be used for data members designated as object identifiers. In
combination with the type pragma, id_type allows you to map a C++ type
differently depending on whether it is used in an ordinary member or an
object id.
* New options, --odb-prologue-file and --odb-epilogue-file, allow the
inclusion of file contents into the ODB compilation.
* Default mapping of the size_t and std::size_t types to a 64-bit integer
database type irrespective of the platform width. This can be overridden
with the type pragma.
Version 1.3.0
* Support for the SQLite database. The provided connection factories include
'new' (a new connection is created every time one is requested), 'single'
(single connection is shared among all the callers), and 'pool' (a pool
of connections is maintained). In multi-threaded applications the runtime
uses the SQLite shared cache and unlock notification features to aid
concurrency. For more information, refer to Chapter 11, "SQLite Database"
in the ODB manual.
* Support for database-specific profiles. Now the ODB compiler first looks
for the <profile>-<database>.options file and only if this file is not
found, does it fall back to <profile>.options.
* Support for the GCC 4.6 plugin interface changes.
Version 1.2.0
* New profile, boost, provides persistence support for the Boost libraries.
This version covers the most commonly used types from the smart_ptr,
unordered, and date_time libraries. The boost profile implementation is
provided by the libodb-boost library. For more information refer to
Chapter 11, "Profiles Introduction" and Chapter 12, "Boost Profile" in
the ODB manual as well as the 'boost' example in the odb-examples package.
* Support for embedded database schemas. The new option, --schema-format,
allows the selection of the schema format. The valid values for this
option are 'sql' for a standalone SQL file and 'embedded' for a schema
embedded into the generated C++ code. The new odb::schema_catalog class
provides support for accessing embedded schemas from within the
application. For details refer to Section 3.3, "Database" in the ODB
manual as well as the 'schema/embedded' example in the odb-examples
package.
* New exceptions: odb::recoverable, odb::connection_lost, and odb::timeout.
The odb::recoverable exception is a common base class for all recoverable
ODB exceptions. The other two exceptions plus odb::deadlock now inherit
from this base. Refer to Section 3.5, "Error Handling and Recovery" for
details.
* Support for connection validation (ping) in MySQL connection_pool_factory.
This transparently deals with the MySQL server closing connections after
a certain period of inactivity.
* New namespace, odb::core, contains using-declarations for the core ODB
constructs, such as the database, transaction, etc. The primary use of
this namespace is in the using-directives:
using namespace odb::core;
The above form should be preferred over the old variant:
using namespace odb;
The new approach brings all the essential ODB names into the current
namespace without any of the auxiliary objects such as traits, etc., which
minimizes the likelihood of conflicts with other libraries. Note that you
should still use the odb namespace when qualifying individual names, for
example, odb::database.
* New option aliases: -q for --generate-query and -s for --generate-schema.
* Support for the default options file. Now, if configured, the ODB compiler
loads the default options file (by default ../etc/odb/default.options,
relative to the ODB compiler binary). This file can be used for
installation-wide customization, such as adding extra include search
paths.
Version 1.1.0
* Support for storing containers in the database. For more information refer
to Chapter 5, "Containers" in the ODB manual as well as the 'container'
example in the odb-examples package.
* Support for unidirectional and bidirectional object relationships,
including lazy loading. For more information refer to Chapter 6,
"Relationships" in the ODB manual as well as the 'relationship' and
'inverse' examples in the odb-examples package.
* Support for composite value types. For more information refer to Chapter
7, "Composite Value Types" in the ODB manual as well as the 'composite'
example in the odb-examples package.
* Support for sessions. A session is an application's unit of work that
may encompass several database transactions. In this version of ODB a
session is just an object cache. For more information refer to Chapter
8, "Session" in the ODB manual.
* Support for custom object pointers that allows you to use smart pointers
to return, pass, and cache persistent objects. See Section 3.2, "Object
Pointers" in the ODB manual for details.
* Support for native SQL statement execution. See Section 3.9, "Executing
Native SQL Statements" in the ODB manual for details.
* New option, --profile/-p, instructs the ODB compiler to use the specified
profile library. See the ODB compiler command line manual for details.
* Support for literal names (template-id, derived type declarator such as
pointers, etc) in data member declarations. Now, for example, you can use
std::vector<std::string> directly instead of having to create a typedef
alias for it.
* Support for inheritance from transient base types for object types and
composite value types.
* New example, 'schema/custom', shows how to map persistent C++ classes to
a custom database schema.
* New options, --odb-prologue, --odb-epilogue, allow inclusion of extra code
into the ODB compilation process. This can be useful for making additional
traits specializations or ODB pragmas known to the ODB compiler.
* Support for persistent classes without default constructors. For objects
of such classes only the load() and find() database functions that
populate an existing instance can be used. Similarly, only the load()
query result iterator function which populates an existing instance can
be used.
Version 1.0.0
* Initial release.
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