You can upgrade the schema of an UltraLite database with the appropriate Data Definition Language (DDL) statements or by using the ALTER DATABASE SCHEMA FROM FILE statement to modify the schema definition using a SQL script.

Schema changes can take a considerable amount of time. For example, all rows in the associated table must be updated when the column type is changed. DDL statements successfully execute when there are not any:

When the DDL statement is executing, any other attempt to use the database is blocked until the DDL statement completes the schema change.

The UltraLite Java edition database schema is maintained as a catalog of system tables that hold the metadata for the UltraLite Java edition database. System table metadata include:

• ALTER DATABASE SCHEMA FROM FILE statement [UltraLite]
• Deploying UltraLite database schema upgrades
• systable system table
• syscolumn system table
• sysindex system table
• sysindexcolumn system table
• syspublications system table
• sysarticles system table
• sysforeignkey system table
• sysfkcol system table
• sysuldata system table