IBM i Series, Руководство пользователя

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Operating System/400 (5722-SS1)
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iSeries Handbook
users to be immediately aware of changes in the database and to access the current
information in their required sequence.
National Language Support (NLS)
Data in multiple national languages can reside in the same table and be accessed across the
distributed database platforms.
NLS allows customers to interact with DB2 UDB for iSeries and store data in their preferred
language, character set, and sort sequence. The ability to store double-byte graphic
characters and compare data in different character sets is also provided.
Conforming with Structured Query Language (SQL) standards supplies the industry standard
database access language with consistent data access across heterogeneous platforms. It
also provides conformance to IBM SQL Version 1, ANSI X3.135.1992, ISO 9075-1992, and
FIPS 127-2 standards. Support is provided for embedded static, dynamic, and extended
dynamic SQL. ANSI-and ISO-defined SQL procedures are also supported.
Large Object Support
With the addition of large objects (LOBs), DB2 UDB for iSeries can store and manipulate data
fields much larger than the current limits. An iSeries record with LOB fields can hold up to
15 MB of data. With the new LOB support, you can look to DB2 UDB for iSeries as a platform
for building applications that hold new data such as very large text, image, and audio.
DATALINK Data Type
The DATALINK data type extends the types of data that can be stored in database files. The
actual data stored in the column is only a pointer to the object such as an image file, a voice
recording, or a text file. The method used for resolving to the object is to store a uniform
resource locator (URL). This means that a row in a table can be used to contain information
about the object in traditional data types, and the object itself can be referenced using the
DATALINK data type. Datalinks also allow the referenced object to be “linked” to the database
to prevent modification or deletion of the object while it is linked to the database file. This
relationship is maintained by having the database interact with the file system.
User-defined Types
User-defined types are derived from existing predefined types such as integer and character.
You can create your own types for strong typing and creating functions for different types.
You can call a function for each row of a result set and return a value based on the
user-defined type.