Displaying Bitmap Pages

In earlier XPS releases, the onutil utility can display a database page from the disk. The DISPLAY PAGE option, when run without the HEX keyword, displays the page header and the body of the page in the appropriate format, for pages that are not bitmap pages. If the page is a bitmap page, however, onutil DISPLAY PAGE can display it only in hexadecimal format. You can use the HEX keyword to display the entire page in hexadecimal format with an ASCII translation of each byte on the right side.

A new feature of XPS 8.51 can use the current DISPLAY PAGE option of the onutil utility to display 2-bit or 4-bit bitmap pages in a more readable text format.

The following subset of the onutil DISPLAY PAGE command-line syntax can specify a bitmap page:

onutil DISPLAY PAGE {page [IN TABLE [dbase:][owner.]table] [ , dbspace ] ] |
                     page [IN INDEX [dbase:][owner.]index  [ , dbspace ] ] |
                     page IN TABLESPACE partnum |
                     chunk:offset} ;

In the onutil DISPLAY PAGE syntax above, the parameters in italics have the following definitions:

• page is the logical page number of a bitmap page to be displayed.
• dbase is the SQL identifier of the database containing table.
• owner is the authorization identifier of the user who owns table.
• table is the SQL identifier of the table that has the bitmap page
• index is the SQL identifier of the index key that has the bitmap page
• dbspace is the number of a dbspace where page resides
• partnum is the number of a tblspace where page resides
• chunk is the number of a chunk where page resides
• offset is the number of pages from the beginning of the chunk where the display begins.

See Chapter 11 of the Administrator's Reference for the complete syntax of the onutil DISPLAY PAGE command.

A page specified as a logical page number must be an unsigned integer no greater than 16,777,215, but the onutil DISPLAY PAGE command also accepts page specified as a physical page address, in the format chunk:offset, where chunk is the chunk number as an unsigned integer, and offset is a unsigned integer that corresponds to the ordinal position of the page within the chunk.

If you use the chunk:offset format to specify the page as a physical page address, rather than as a logical page number, the database server assumes that page is a 4-bit bitmap.

• If page is a 2-bit bitmap, the output will not be useful, and a warning message is issued, indicating that page was assumed to be a 4-bit bitmap.
• If page is a 4-bit bitmap, the output will be useful, despite your substitution of a physical page address in a context where a logical page number is expected for bitmap pages.

Only the resulting output differs from the behavior of XPS 8.50, whose syntax for onutil DISPLAY PAGE is unchanged by this feature.

For more information about command-line options of the onutil utility, see Appendix A. Syntax Summaries of Selected Utilities.