Check it out here
I'll post more about how I've extrapolated records from derived column values, but I am looking for suggestions (more...)
You may have previously seen a short post I did on a SQL statement to identify which statements are using dynamic sampling.
If not, quick recap:
SELECT p.sql_id, t.val FROM v$sql_plan p , xmltable('for $i in /other_xml/info where $i/@type eq "dynamic_sampling" return $i' passing xmltype(p.other_xml) columns attr (more...)
As your data volumes increase, particularly as you evolve into the big data world, you will be start to see that your Oracle Data Mining scoring functions will start to take longer and longer. To apply an Oracle Data Mining model to new data is a very quick process. (more...)
In Oracle 11G, Oracle introduced SQL Plan Management (SPM). It is excellent (I love it to bits). It allows you to create Baselines against SQL which lock-down the SQL execution plan. No more plan flips. More consistency. Perfect.
Whenever some Baselined SQL is ran, Oracle still parses it and compares (more...)
Just a quick code snippit. I do a lot of data pumps to move schemas between different databases; for example taking a copy of a schema to an internal database to try to reproduce a problem. Some of these schemas have some very large tables. The large tables aren’t always (more...)
When he (more...)
Recursive subquery factoring (AKA Recursive Common Table Expressions) has been available in Oracle since version 11g R2 was launched sometime around 2009. I always thought of it as a replacement for the connect by clause and just another way to write hierarchical queries, so I never really took the time (more...)
(blog post in Azerbaijani)
Azərbaycan dilində informasiya texnologiyaları movzusunda yazılmış kitab çox azdır. Bu tip kitabların az olmasının ən böyük səbəbi İT sahəsinə aid rəsmi terminaloji tərcümənin olmamasıdır. Buna baxmayaraq son illərdə bir neçə texniki nəşrlə tanış olmaq imkanım olmuşdur. Bu kitablardan biri Samir Səmədov (OCM11g, www.ocm. (more...)
He wanted the data in the columns to be "shifted to the left". To explain a little more, take a look at the following data:
ID V1 V2 (more...)
It seems that sometimes you need a non-unique index to enforce a unique constraint even if this constraint is declared as not deferrable.
firstname.lastname@example.org > create table strange(i int not null, j int not null); Table created. email@example.com > alter table strange add constraint unique_i unique(i) not deferrable (more...)
with t as (
select null n from dual union all
select 0 from dual union all
select 0.5 from dual union all
select 4 from dual union all
select 4. (more...)