DB2 UDB for z/OS Version 8 Performance Topics - IBM Redbooks

Batch updates
A batched update is a set of multiple update statements that are submitted to the database for
processing as a batch. Sending multiple update statements to the database together as a unit
can, in some situations, be much more efficient than sending each update statement
separately. It reduces the number of times the application has to cross over to the JDBC
Driver. This ability to send updates as a unit, referred to as the batched update facility, is one
of the features of the JDBC 2.0 API, and is now supported with the DB2 Universal Driver.
7.4 ODBC enhancements
ODBC enhancements are mentioned for completeness.
7.4.1 ODBC Unicode support
ODBC now supports Unicode formats UTF-8 and UCS-2. In addition, a new ODBC
initialization keyword, CURRENTAPPENSCH, lets you specify the encoding scheme that you
want the ODBC Driver to use for input and output of host variable data, SQL statements, and
all character string arguments of the ODBC application programming interfaces. You can
specify Unicode, EBCDIC, or ASCII encoding scheme.
7.4.2 ODBC long name support
ODBC for z/OS has been enhanced to be able to support the long names in V8 new-function
mode. This means changes to the following ODBC functions.
Support for longer names in the INI file variables
The keyword strings for the following initialization keywords will be extended to support longer
names:
► CLISCHEMA
► COLLECTIONID
► CURRENTFUNCTIONPATH
► CURRENTSQLID
► SCHEMALIST
► SYSSCHEMA
ODBC catalog functions
As a result of the name changes in the catalog, the ODBC catalog API needs to change the
lengths of the host variables and data types in the SQLDA when fetching result sets from
catalog tables. However, most of these changes are transparent to the external API. Only the
data type of the REMARKS column returned by SQLColumns() and SQLTables() is changed
to VARCHAR(762).
7.4.3 ODBC connection authentication
With V7, the DB2 ODBC Driver validates the user ID and password, but their argument values
are not used for end user authentication. DB2 V8 implements the RACF verification support
for USER/USING SQL CONNECT statement, and the ODBC Driver makes use of the user ID
and password values provided on the APIs to perform authentication.
306 DB2 UDB for z/OS Version 8 Performance Topics