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Firebird Backend Reference

SOCI backend for accessing Firebird database.

Prerequisites

Supported Versions

The SOCI Firebird backend supports versions of Firebird from 1.5 to 2.5 and can be used with either the client-server or embedded Firebird libraries. The former is the default, to select the latter set SOCI_FIREBIRD_EMBEDDED CMake option to ON value when building.

Tested Platforms

Firebird OS Compiler
1.5.2.4731 SunOS 5.10 g++ 3.4.3
1.5.2.4731 Windows XP Visual C++ 8.0
1.5.3.4870 Windows XP Visual C++ 8.0 Professional
2.5.2.26540 Debian GNU/Linux 7 g++ 4.7.2
2.5.8.27089 macOS High Sierra 10.13.5 AppleClang 9.1.0.9020039

Required Client Libraries

The Firebird backend requires Firebird's libfbclient client library. For example, on Ubuntu Linux, for example, firebird-dev package and its dependencies are required.

Connecting to the Database

To establish a connection to a Firebird database, create a Session object using the firebird backend factory together with a connection string:

BackEndFactory const &backEnd = firebird;
session sql(backEnd, "service=/usr/local/firbird/db/test.fdb user=SYSDBA password=masterkey");

or simply:

session sql(firebird, "service=/usr/local/firbird/db/test.fdb user=SYSDBA password=masterkey");

The set of parameters used in the connection string for Firebird is:

  • service
  • user
  • password
  • role
  • charset

The following parameters have to be provided as part of the connection string : service, user, password. Role and charset parameters are optional.

Once you have created a session object as shown above, you can use it to access the database, for example:

int count;
sql << "select count(*) from user_tables", into(count);

(See the connection and data binding documentation for general information on using the session class.)

SOCI Feature Support

Dynamic Binding

The Firebird backend supports the use of the SOCI row class, which facilitates retrieval of data whose type is not known at compile time.

When calling row::get<T>(), the type you should pass as T depends upon the underlying database type. For the Firebird backend, this type mapping is:

Firebird Data Type SOCI Data Type row::get<T> specializations
numeric, decimal (where scale > 0) dt_double double
numeric, decimal [^1] (where scale = 0) dt_integer, dt_double int, double
double precision, float dt_double double
smallint, integer dt_integer int
char, varchar dt_string std::string
date, time, timestamp dt_date std::tm

[^1] There is also 64bit integer type for larger values which is currently not supported.

(See the dynamic resultset binding documentation for general information on using the Row class.)

Binding by Name

In addition to binding by position, the Firebird backend supports binding by name, via an overload of the use() function:

int id = 7;
sql << "select name from person where id = :id", use(id, "id")

It should be noted that parameter binding by name is supported only by means of emulation, since the underlying API used by the backend doesn't provide this feature.

Bulk Operations

The Firebird backend has full support for SOCI bulk operations interface. This feature is also supported by emulation.

Transactions

Transactions are also fully supported by the Firebird backend. In fact, an implicit transaction is always started when using this backend if one hadn't been started by explicitly calling begin() before. The current transaction is automatically committed in session destructor.

BLOB Data Type

The Firebird backend supports working with data stored in columns of type Blob, via SOCI BLOB class.

It should by noted, that entire Blob data is fetched from database to allow random read and write access. This is because Firebird itself allows only writing to a new Blob or reading from existing one - modifications of existing Blob means creating a new one. Firebird backend hides those details from user.

RowID Data Type

This feature is not supported by Firebird backend.

Nested Statements

This feature is not supported by Firebird backend.

Stored Procedures

Firebird stored procedures can be executed by using SOCI Procedure class.

Native API Access

SOCI provides access to underlying datbabase APIs via several get_backend() functions, as described in the Beyond SOCI documentation.

The Firebird backend provides the following concrete classes for navite API access:

Accessor Function Concrete Class
session_backend * session::get_backend() firebird_session_backend
statement_backend * statement::get_backend() firebird_statement_backend
blob_backend * blob::get_backend() firebird_blob_backend
rowid_backend * rowid::get_backend()

Backend-specific extensions

firebird_soci_error

The Firebird backend can throw instances of class firebird_soci_error, which is publicly derived from soci_error and has an additional public status_ member containing the Firebird status vector.