I've been playing around with MATCH_RECOGNIZE - the data pattern matching extension to SELECT that was introduced in version 12.
Most examples I've seen have used the default AFTER MATCH SKIP PAST LAST ROW as most often the logic dictates, that when we have found a match in a group of rows, we want to search for further matches after
those rows to avoid unwanted "double" matches.
But can there be uses where we want (more...)
Last week we began testing a copy of our production database on Oracle 12c (184.108.40.206). This past weekend we were alerted that the disk holding our ADR diagnostic directory was near full. We noticed some pretty big (and recent) trace files there. Then it happened twice more. This last time filled the disk before we could get to it (thankfully only dev, and during the evening), meaning it filled up fast. The (more...)
Inspired by a presentation given by Shukie Ganguly on the free Oracle Virtual Technology Summit in July (see here); “New APIs and Tools for Application Development in WebLogic 12c”, I decided to take a look at an interesting new feature in WebLogic Server 12c: the RESTful Management Services. You can see here how to enable them. In this post I will provide an overview of my short study on the topic.
RESTful management services (more...)
Today my presentation is confirmed: “Bob the Builder: Build/Deploy of ADF enterprise applications”.
I will speak over our experiences with following
- build tools
- deployment tools
- versioning & branching
- continuous integration
- hot deployment in development
- compile & runtime dependencies
If you speak german and you are interested in some of this, you should come and attend DOAG 2015.
Filed under: Deploying
, ADF Architecture
Sometimes you want to cancel your Integrated WebLogic Server, however, if you do this while a deployment is currently going on, you might run into trouble. The log window will not tell you anymore than a remote deployment failed and that the Application can not be run:
You need to clear some directories in your JDevHome before the application deployment works again. Before clearing the directories, make sure you close JDeveloper.
Go to the folder: (more...)
This post is just a compilation of the links to other people’s articles and short descriptions about new SQL PLAN OPERATIONS and HINTS with a couple little additions from me.
This one is a nasty bug I was trying to setup Oracle PDB in a test environment for the first time and got stuck with ORA-01035 error [oracle@oracle11g ~]$ sqlplus hr/hr@//oracle11g:1522/engg SQL*Plus: Release 220.127.116.11.0 Production on Fri Jul 3 07:34:58 2015 Copyright (c) 1982, 2014, Oracle. All rights reserved. ERROR: ORA-01035: ORACLE only available to users with…
If you work with JDeveloper 12.1.3 you may missing the return type of methods in completion insight.
For an example you hit CTRL-SPACE after following code
you see that at the start and at the end of the popup the available method names and parameter. If you have worked before with older versions of JDeveloper, you know that there is shown the return type of the method at the end. What a loose of (more...)
Note to self because it’s just one of those date/timezone-related topics which just doesn’t seem to stick…
Epoch/Unix time – See https://en.wikipedia.org/wiki/Unix_time
Unix time (also known as POSIX time or erroneously as Epoch time) is a system for describing instants in time, defined as the number of seconds that have elapsed since 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970,
Firstly when converting from Oracle date or timestamp – we need to (more...)
I’ve previously discussed Index Tree Dumps but I’ve recently found a nice little improvement that’s been introduced in Oracle Database 12c. Let’s begin by creating a little table and index: To generate an Index Tree Dump, we first need to OBJECT_ID of the index: And then use it to generate the Index Tree Dump: Previously, an […]
event histogram metric, a script and some related comments on collecting and displaying wait event latency histograms for Oracle performance troubleshooting.Why:
Latency histograms (and by extension wait event histograms) provide very useful information when troubleshooting performanc
e for systems exhibiting response time with multi-mode distribution. In such cases average wait values are often not sufficient to understand the behavior of the system under study and histograms
provide a finer level of details. A (more...)
I’ve never really spent time on evolution because most of the time I use baselines for emergency sql plan management and not with the added value of controlled evolution with which the feature was conceived.
But some observations on sql plan baseline evolution originating from the questions:
- What does evolution actually do?
- What information does it use?
- What happens with DML?
Starting point – one baselined plan
1. FTS plan in memory from SQL which (more...)
Execution Plan Instability – What is the problem?
The Oracle Optimizer is a complex piece of software and with every release it becomes more complex.
In the beginning, the Optimizer was rule-based.
The Optimizer had a ranked list of heuristics used to optimize a query, picking the lowest ranked rule available.
This rule-based mode, whilst still in use with some internal Oracle dictionary queries, has been unsupported since version 10.1.
This means that (more...)
The table has 9M rows:
SQL> with function f return int is
3 for r in (select value from v$mystat natural join v$statname where name like 'IM scan rows') loop
5 return r.value;
6 end loop;
8 select f() from t_inmemory where rownum<=1
1 row selected.
1 row selected.
Yeah, it’s indeed true and official. So if you still haven’t started reading and learning Multitenant architecture introduced in 18.104.22.168 and enhanced in 22.214.171.124, it’s high time that you start doing it. Not because that it’s new but because the old architecture you are familiar with, it’s officially on the verge of extinction.
Recently we came across a issue where our DB crashed with ORA-00338 error . Errors in file /oracle/diag/rdbms/orcl11g/orc11g/trace/orc11g_lgwr_24118.trc: ORA-00338: log 2 of thread 1 is more recent than control file ORA-00312: online log 2 thread 1: '/oracle/oradata/orcl11g/redo02.log' LGWR (ospid: 24118): terminating the instance due to error 338 DB couldn't be restarted as it gave same errors…
Ever want to run a Stored Procedure or a PL/SQL anonymous block and just want to "print out" the results of a query ? Even as a little bit of debug information?
In Oracle 11g you have to create a SQL*Plus REFCURSOR variable and then bind it within the anonymous block or pass it as an argument to a procedure/function. Run the code and then print the refcursor.
This requires a bit of know how in (more...)