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This default ordering will last as long as there are no changes in the table
(no insertions, deletions, or updates). This is why phpMyAdmin shows the
(singly) warning.
After the sort has been done on author_id, books for author 1 will be displayed
first, followed by the books for author 2, and so on. (We are talking about a default
browsing of the table without explicit sorting.) We can also specify the sort order:
Ascending or Descending.
If we insert another row, describing a new book from author 1, and then click
Browse, the book will not be displayed along with the other books for this author
because the sort was done before the insertion.
Table Options
Other attributes that influence the table's behavior may be specified using the Table
options dialog:
The options are:
pack_keys: Setting this attribute results in a smaller index; this can be read
faster but takes more time to update. Available for the MyISAM storage engine.
checksum: This makes MySQL compute a checksum for each row. This
results in slower updates, but easier finding of corrupted tables. Available for
MyISAM only.
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delay_key_write: This instructs MySQL not to write the index updates
immediately but to queue them for later, which improves performance.
Available for MyISAM only.
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