Compatibility Issues

Dmitry Yemanov

Table of Contents

Effects of Unicode Metadata
Configuration Parameters Removed
SQL Language Changes
Utilities
API Changes
Security Hardening
Access Path for Services
Known Platform Issues

For migrating v.2.0.x or v.2.1.x databases to Firebird 2.5, a number of incompatibilities that are likely to affect existing databases or existing applications should be noted. It is not recommended that you begin a migration until you have resolved these.

Incompatibility with Older Clients

To enable the 32-bit tools to work correctly with new structures that enable statistics routines to work properly with a 64-bit server, it was necessary to introduce some new internal API functions (struct perf64 and perf64_xxx) and change isql and qli to use them. This means that the isql and qli programs in V.2.5 are not compatible with older Firebird clients.

For more information, see the topic Statistics Now Work Properly with 64-bit Values in the Engine chapter.

Effects of Unicode Metadata

If you have not previously updated text objects within the metadata of your databases to be in character set UTF8, restoring a database until V.2.5 will fail with “malformed string” errors. To resolve this it is necessary to pay attention to the files in the /misc/upgrade/metadata directory of your installation and to use the new -fix_fss_data and -fix_fss_metadata switches in the gbak command line.