At Oracle OpenWorld 2013, I attended a presentation by Jonathon Lewis, who of course is one of the world’s leading Oracle experts especially when it comes to the Cost Based Optimizer (CBO). As is usually the case, the room was completely packed for his presentation. He had a co-presenter, Maria Colgan who works for Oracle …
Category: Oracle
Sep 27
Back from Open World 2013
I am back from Oracle Open World 2013. This was my first Open World conference. I knew it was big but I was still unprepared for the overall size. Approximately 60,000 people attended the conference. I really doubt that it is possible to take in all that the conference offers in one week’s time. There …
Sep 17
12c Move Datafiles Online
Prior to Oracle 12c, if you wanted to move a database’s file, you either had to shutdown the database, or take the datafile/tablespace offline. Here is an example of the steps you might take: ALTER TABLESPACE my_ts OFFLINE; !mv /old_dir/my_ts01.dbf /new_dir/my_ts01.dbf ALTER DATABASE RENAME FILE ‘/old_dir/my_ts01.dbf’ TO ‘/old_dir/my_ts01.dbf’; ALTER TABLESPACE my_ts ONLINE; Now in Oracle …
Sep 17
12c Adaptive Plans
I’ve been meaning to write something up on Oracle 12c’s new Adaptive Plans. When I do have poorly performing SQL statements, it seems that the issue is often due to bad optimizer stats. Recalculate the stats and performance is improved. I like the new 12c feature of Adaptive Plans where the database engine will reformulate …
Sep 05
12c Data Redaction
Oracle 12c’s Advanced Security option now includes Data Redaction. This is a great way to secure your data , transparently to the application, from prying eyes. If an end user does not need the entire tax id, they can be presented with just the last four digits, as an example. To me, this is just …
Sep 05
ORA-01097
Every once in a while, a person comes across something that has been around forever but is a new experience for them. Just today, I hit the ORA-1097 error for the first time in my career. I was in a test database and needed to shut it down. SQL> shutdown immediate ORA-01097: cannot shutdown while …
Aug 26
SQL Developer 4
As time goes on, I am becoming more and more of a big fan of SQL Developer. I use this product daily and I often have many windows open to do my work. SQL Developer 4 is in Early Adopter phase. You can get a copy of it here: http://www.oracle.com/technetwork/developer-tools/sql-developer/downloads/sqldev-download-v4-1925679.html My only complaint with the …
Aug 07
oratop
I was recently made aware of a new Oracle-supplied utility named oratop. This professed to be a tool similar to the Unix/Linux top utility, but for Oracle databases. I have now had a chance to use this and play around with it a bit. If you want to download the utility, visit Metalink Note 1500864.1 …
Aug 01
12c DBA_USERS Changes
Today, I was looking at the ability to query a user’s last login time. Prior to 12c, one had to create a logon trigger to store the logon time in a table or set up auditing and audit successful logins. Now, Oracle 12c includes, by default, a way to determine the last time someone logged …
Jul 31
12c VARCHAR2(32767)
I’ve always wondered why the VARCHAR2 datatype was limited to so few characters. For most attributes, you do not need more than 2,000 bytes. I remember when Oracle upped the limit from 2,000 bytes to 4,000. But SQL Server 2008R2 lets you use 8,000. We are talking about character data and the 2,000 or 4,000 …
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@sacrophyte That was an old recommendation which is probably out of date now. When I look at the 19c doc for that p… https://t.co/h0VwGJECvH
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Also in that note is "We decided to not promote our Database 20c Preview version to General Availability. Instead,… https://t.co/bvUcRKQ9gt
