TweetShareSharePin0 SharesI’m going to discuss how to get SQL access to your alert log in this entry. I will then build on that to make it even more useful in future posts. Browsing the alert log can be convenient if you’re already on the server. However, it is often not possible or at least not overly convenient. You may find that as the developer DBA you do not have access to the production server, or you have to log in […]
Oracle
Multitable insert
TweetShareSharePin0 SharesMutlitable insert is a feature I’ve read about many times, but I’ve never taken the time to read up on it or play with the way this SQL statement works. I figure making a post about it will give me the reason I need to learn more about it. It is not so much a new statement as an extension of the existing INSERT statement. It allows you to insert into different tables and with different conditions from a […]
Commit and snapshot too old
TweetShareSharePin0 SharesThe dreaded ORA-01455 hits again. Snapshot to old is easy to understand, but not always easy to fix. In this article I’ll show how the misbehaving process may actually be the process that receives the error. Snapshot too old is the problem we encounter if the block you need to access cannot be found. This doesn’t mean that the block has been misplaced by the database, but rather that the version of it that you need is no longer […]
Learning SQL at an early age
TweetShareSharePin0 SharesPete Finnegan blogged about becoming a dad a few days back and Gary Myers followed up with his version of an SQL Primer for a toddler. This got me thinking of how the child subjected to this may react . As having SQL read out loud even with pictures from the result set may not really be all that enjoyable for a new born or even at four years of age, maybe the first reaction would be. After a […]
The WITH clause
TweetShareSharePin0 SharesTo mix the last post with something that may be easier to digest, I’ll make this one about one of my favorite keywords in SQL. It is the WITH clause. I can only think of one bad thing with it; it’s name. It’s virtually impossible to search for information on something with a name that results in over 4 billion hits on a Google search. One reason for why I like it is for how I learned about it’s […]
Commit frequency and Undo
TweetShareSharePin0 SharesToo frequent commits can lead to performance problems, but can it also affect how much undo the updates generate? The fact that very frequent committing causes performance problems has been noticed by almost every Oracle developer with even just a couple of months experience with the Oracle database. However, if commit can increase I/O requests issued by the database, then this would also impact the performance of other processes. With Oracle, that can be done in many ways, but […]