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The Firebird ODBC driver supports multiple simultaneous connections to different databases and different servers, each connection operating independently of any others.

Multithreading

Thread protection can be specified at two levels:

  1. sharing an environment handle

  2. sharing a connection handle

By default, the driver is built using the following define:

#define DRIVER_LOCKED_LEVEL     DRIVER_LOCKED_LEVEL_CONNECT

which enables a single connection to share multiple local threads.

The default setting is reflected in the initial setup of the DSN on Windows: SAFETHREAD=Y.

If the driver is built using the following define:

#define DRIVER_LOCKED_LEVEL     DRIVER_LOCKED_LEVEL_NONE

then the driver is built without multi-threading support and responsibility for threading control is transferred to the Firebird client library.This provides for fastest performance.

If you have a build that was made with this define, you should make it the default thread behaviour for the DSN by configuring SAFETHREAD=N in its interface.

If the driver is built using the following define:

#define DRIVER_LOCKED_LEVEL     DRIVER_LOCKED_LEVEL_ENV

then a single environment handle can be shared by multiple local threads.

Note

You may save a specific set of connection conditions or overrides in a FILEDSN.