If we look again at the first bookmark we created (finding all books for author 1), we realize that, although useful, it was limited to always finding the same author.
A special query syntax enables the passing of parameters to bookmarks. This syntax uses the fact that SQL comments enclosed within /*
and */
are ignored by MySQL. If the /*[VARIABLE]*/
construct exists somewhere in the query, it will be expanded at execution time with the value provided when recalling the bookmark.
Let's say we want to find all books for a given author when we don't know the author's name. We first enter the following query:
SELECT author.name, author.id, book.title
FROM book, author
WHERE book.author_id = author.id
/* AND author.name LIKE '%[VARIABLE]%' */
The part between the comments characters (/* */
) will be expanded later, and the tags removed:
We label it and click Go. The first execution of the query just stores the bookmark.
In this example, we have...