セッション・データ・ユニット（session data unit: SDU）
Oracle Netがネットワーク間でデータを転送する前にデータを配置するバッファ。Oracle Netがバッファ内のデータを送信するのは、データ送信が要求されたとき、またはバッファがデータでいっぱいになったときである。
Lindsay Hamilton of Cervello Consultants has just started a new blog aimed at data security, data breaches and data security vulnerability scanning and activity monitoring. This should be worth watching as data breaches are certainly an in topic subject with....[Read More]
Posted by Pete On 03/08/10 At 04:18 PM
This post originally appeared over at Pythian. There are also some very smart comments over there that you shouldn’t miss, go take a look!
I spent some time last month getting up to speed on MySQL. One of the nice perks of working at Pythian is the ability to study during the workday. They could have easily said “You are an Oracle DBA, you don’t need to know MySQL. We have enough REAL MySQL experts”, but they didn’t, and I appreciate.
There are only three join mechanisms used by Oracle: merge join, hash join and nested loop join. Here’s an important thought: all three join methods are nested loop joins with different startup cost. Discuss. (I’ll be saying more about this in about a week’s time.) And while I’m asking questions: what’s the perfect tense of [...]
When two tables are equi-partitioned on their join keys, the query optimizer is able to take advantage of partition-wise joins. To make sure that the tables are equi-partitioned, as of Oracle Database 11g reference partitioning can be used. In fact, per definition, with reference partitioning all “related” tables have exactly the same partitioning schema. If [...]
比較対象としたのは、Western Digital社のWD6000HLHX。SATAIII 6Gb/秒で接続可能な10,000 RPMハードドライブ
SQL> desc orders
名前 NULL? 型
----------------------------------------- -------- ----------------------------
O_ORDERKEY NOT NULL NUMBER
O_CUSTKEY NOT NULL NUMBER
Back on June 17th WordPress 3.0 “Thelonious” was released and it offered up a handful of new features. Just a few days ago (July 29th) the 3.0.1 release went GA so I decided it was time to investigate what the new 3.0 ready themes had to offer. After looking through a handful of themes I decided to give the Magazine Basic theme a try for now. It offered a 1024 pixel wide layout and threaded comments; two of the features I was really looking for. Feel free to share your comments: good, bad or otherwise. Thanks! Here is a capture of the previous version just in case you don’t recall what it looked like (click for full size).