Display a blob

I have a table with a blob create table t(b blob); insert into t values (‘585858’); In 11g sql*plus, I can display raw data select b from t; B —— 585858 Ok, but if I want to display XXX (the character content) select utl_raw.cast_to_varchar2(b) from t; UTL — XXX However, in sql, a raw cannot […]

On associativity, transitivity and reflexivity

Addition is supposed to be associative. a+(b+c)=(a+b)+c This may be wrong in Oracle when dealing with months and days with t as (select interval ‘1’ month a, date ‘2007-09-26’ b, interval ‘7’ day c from dual) select a+(b+c),(a+b)+c from t; A+(B+C) (A+B)+C ———– ———– 03-NOV-2007 02-NOV-2007 The equality is supposed to be transitive if (a=b […]

OOW schedule

I have start building my schedule. There are about 1722 sessions to chose from this year, so choice is difficult! Due to jet-lag, I mostly cannot do all what I planed. And I also like to spent some time by the exhibitors and the boosts. Ok, the one I will not miss : Steven Feuerstein […]

SIG SOUG: times ten

I have been to a SOUG last Thursday. We first had a presentation from Thomas Koch about performance in Zurich Kantonalbank. As I have been working as a DBA for about two years in that bank, I already had my opinion about performance there 😕 The second presentation was about TimesTen. I must say I […]

Please RTFOM !

Today I opened two SR about flashback archive in 11g. In one of them, I complained that user SCOTT was not allowed to create a flashback archive. In the doc that I downloaded a few weeks ago I read : Prerequisites You must have the FLASHBACK ARCHIVE ADMINISTER system privilege to create a flashback data […]

isNumber in sql

I tried this in 11g TABLE T X 123 -1.2e-3 abc select x, to_number( xmlquery(‘number($X)’ passing x as x returning content)) n from t; X N ——- ———- 123 123 -1.2e-3 -.0012 abc it is quite a common task to extract numbers from varchar2 and to dig out poor quality data. select x, to_number(x) from […]

installing OID 10.1.4.2 Preview 1

Download oracle-oid-10.1.4.2.0-1.0.i386.rpm Download oracle-xe-univ-10.2.0.1-1.0.i386.rpm Install the rpm # rpm -i oracle-*.i386.rpm In SLES 10, there is no /bin/cut, let’s create a link as root to avoid a mistake when running config-oid.sh # ln -s /usr/bin/cut /bin/cut Run the configure script as root # /etc/init.d/oracle-oid configure That’s all folks! It created an Oracle XE 10gR2 database, […]

Oracle Database 11g: The Top Features for DBAs and Developers

I am always delighted to read the top features by Arup Nanda. He started his 11g series : Oracle Database 11g: The Top Features for DBAs and Developers There are many partitioning enhancements. The most exciting feature for me is the INTERVAL partitioning. A huge cause of downtime and waste of storage is the range […]