Migration to Unicode Applications
If you are migrating to Unicode-enabled applications where the schemas need to use Unicode string types (nchar, nvarchar, long nvarchar) then existing schemas need to be updated to the use the Unicode data types and existing data needs to be converted to Unicode.
Two tools are available for performing this operation:
• copydb or unloaddb command with the -nvarchar flag
• convtouni command, which performs in place conversion
Using either tool will result in databases using Unicode string types and converted data.
The ‑nvarchar flag on copydb or unloaddb exports strings in UTF-8 encoding so that the data files are portable. In the generated scripts, column data types char, varchar, and long varchar on CREATE TABLE statements are changed to nchar, nvarchar, and long nvarchar, respectively. Using the ‑nvarchar flag is useful when the target database is part of an Actian Vector installation, which defaults the character set to UTF8.
IMPORTANT! If you run unloaddb –nvarchar from a client, the client must use the same II_CHARSET as used by the applications that generated the database content; otherwise, the transliteration will be wrong and the target database will be corrupted. Running unloaddb on the server side is preferred.
For details and restrictions on the ‑nvarchar flag, see Portable Data Files in the Database Administrator Guide. For details on convtouni, see the Command Reference Guide.
Last modified date: 01/30/2023