VMS Help  —  SQL72  System Tables, Special Notes, LIST OF BYTE VARYING Metadata
    Oracle Rdb has supported multiple segment LIST OF BYTE VARYING
    data types for user-defined data. However in previous versions,
    Oracle Rdb maintained its own LIST OF BYTE VARYING metadata
    columns as single segments. This restricted the length to
    approximately 65530 bytes. An SQL CREATE TRIGGER or CREATE MODULE
    statement could fail due to this restriction.

    This limit was lifted by changing the way Oracle Rdb stores its
    own metadata.

    o  For columns containing binary data, such as the binary
       representation of query, routine, constraint, trigger action,
       computed by column, or query outline, Oracle Rdb breaks the
       data into pieces that best fit the system storage area page
       size. Thus, the segments are all the same size with a possible
       small trailing segment.

       The LIST OF BYTE VARYING column value is no longer fragmented,
       improving performance when reading system metadata.

    o  For columns containing text data such as the SQL source
       (for elements such as triggers and views) and user-supplied
       comment strings, Oracle Rdb breaks the text at line boundaries
       (indicated by ASCII carriage returns and line feeds) and
       stores the text without the line separator. Thus, the segments
       are of varying size with a possible zero length for blank
       lines.

       An application can now easily display the LIST OF BYTE VARYING
       column value and the application no longer needs to break up
       the single text segment for printing.

    No change is made to the LIST OF BYTE VARYING column values
    when a database is converted (using the RMU Convert command, RMU
    Restore command, or SQL EXPORT/IMPORT statements) from a previous
    version.

    Applications that read the Oracle Rdb system LIST OF BYTE VARYING
    column values must be changed to understand multiple segments.
    Applications that do not read these system column values should
    see no change to previous behavior. Tools such as the RMU Extract
    command and the SQL SHOW and EXPORT statements handle both the
    old and new formats of the system metadata.
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