Storing Unicode data

Db2 for z/OS® supports the full Unicode character repertoire, or set of characters. You can store Db2 data as UTF-8 or UTF-16.

Deciding whether to store data as UTF-8 or UTF-16
If you create a Unicode database in Db2 for z/OS, you need to decide whether to use UTF-8 or UTF-16. Db2 for z/OS does not support storing data as UTF-32. UTF-8 and UTF-16 can both represent any Unicode character that you need to represent, but each format has advantages and disadvantages depending on your situation.
Creating a Unicode table
If you plan to store Unicode data, create Unicode tables. If you try to insert Unicode data into an ASCII or EBCDIC table, data might be lost, unless you use escaped data.
Inserting data into a Unicode table
Unicode tables can store any characters. For characters that you can type on your keyboard, INSERT statements are straightforward. But suppose that you want to insert a character that is not on your keyboard, such as the yen sign (¥) on the U.S. keyboard. That process requires some extra steps.
Inserting Unicode data into a non-Unicode table
If you insert Unicode data into an EBCDIC or ASCII table, use escaped data for those characters that cannot be represented in the target encoding scheme. Using escaped data ensures that those characters are preserved.
Converting existing Db2 data to Unicode
If your database and applications handle international data, consider converting your Db2 data to Unicode. Using Unicode might prevent character conversions and thus improve performance and help ensure data integrity. However, Unicode data might require more space. Depending on the data, these characters can be two to three times the size of EBCDIC or ASCII characters.
Effects on access paths when converting data to Unicode
If you convert your data to Unicode, the access paths for queries on that data do not change simply because the data is now in Unicode. However, valid reasons might exist for a change in the access path for a Unicode table.

Parent topic: International data and character conversion in Db2 for z/OS

Related concepts

Unicode

Related reference

UTFs