Databases
All that is not covered by the Oracle Database…
Implementing Web Services backed by a Database PL/SQL API using the Oracle Service Bus
1This article accompanies an article on the Architecture section of Oracle Technology Network (OTN): Implementing the Enterprise Service Bus Pattern to Expose Database Backed Services. It provides a detailed description of the implementation of the ESB architecture design pattern – the same that is introduced in the article on OTN – using Oracle Service Bus. This OSB based implementation is in terms of structure, architecture design and functionality the replica of the pure Java based implementation described in the OTN-article. OSB adds productivity, agility and many run time administrative benefits over the pure Java solution.
The challengeThe challenge the organization – let us call them Stuff Inc. – is facing is simple and common: external parties have requested access to information through Web Services. This information is held in the enterprise (Oracle) database at Stuff Inc.
The architecture team decides that the implementation of the service should be done according to the ESB architecture pattern.
Their initial implementation is based on custom Java Classes, XSLT stylesheets and JDBC calls.
After some time having worked with this initial set up, they decide to More >
2 dagen seminar door Steven Feuerstein: Best of Oracle PL/SQL (8 en 9 december)
0Steven Feuerstein
In dit tweedaagse seminar neemt Steven Feuerstein je mee ver voorbij de basismogelijkheden van PL/SQL. Steven zal tijdens dit seminar de best practices behandelen die hij op tientallen plekken in de wereld heeft verzameld en die hij ook mede door zijn nauwe samenwerking met het PL/SQL product team van Oracle kan verifiëren en aanscherpen. Hij laat via code-voorbeelden en interactieve sessies zien hoe je als ontwikkelaar in staat bent om snel, hoogwaardige, goed onderhoudbare en uitbreidbare applicaties kunt maken.
Er is tijdens dit seminar voldoende ruimte om vragen te stellen en ideeën met Steven Feurestein uit te wisselen.
Bij dit seminar zijn de volgende zaken inbegrepen:
- Een exemplaar van het boek Oracle PL/SQL Programming (5th edition) van Steven Feuerstein (twv €71,-).
- Een PL/SQL quiz onder leiding van Steven Feuerstein met leuke prijzen.
- Ook ontvang je een gratis jaarabonnement op het PL/SQL Channel. Hiermee heb je toegang tot 27 uur videotraining (normaal $395).
Dit is de kans om in Nederland in een select gezelschap met één van de experts op PL/SQL gebied kennis te maken en je expertise in  Oracle PL/SQL verder te vergroten. Meer More >
Masterclass Advanced Oracle SQL – vrijdag 14 oktober 2011
0Aanstaande vrijdag geef ik voor de derde keer de Masterclass Advanced Oracle SQL. Deze MC gaat over SQL – dat zal duidelijk zijn. We gaan de mogelijkheden van SQL in de Oracle Database verkennen. Van voor naar achter en tot in de diepte. Want SQL is veelzijdig – en veelzijdiger dan de meeste zelfs ervaren database ontwikkelaars en DBAs zich realiseren. Mijn doel met deze MC is om deelnemers te laten zien wat er met SQL mogelijk is en vooral waar SQL een krachtiger en eleganter alternatief is voor PL/SQL of andere applicatie code (Java, .Net, PHP etc.). Als het kan in SQL, kan het zelden beter op een andere manier.
Een paar van de onderwerpen die we bespreken:
- inline views and query refactoring
- scalar subquery
- recursive querying (betere aanduiding van hierarchical queries)
- rollup, pivot and unpivot
- (new) outer join syntax and partition outer join
- analytical functions (of course), primarily lead and lag
- Flasback Versions (in addition to Flashback Query)
- Regular Expressions
Daarnaast is er ook nog wel wat gelegenheid om een paar van de highlights en toekomstige ontwikkelingen rondom de database, SQL en NoSQL van de vorige week More >
Implementation of a moderately complex data constraint business rule using RuleGen 3.0
4In a previous article, I have introduced RuleGen 3.0 – a 2nd generation business rule implementation framework for the Oracle Database: http://technology.amis.nl/blog/?p=12807. RuleGen provides a solid, structured, scalable framework for database developers to implement data constraints in. This article demonstrates how a moderately complex rule is analyzed and designed and implemented with RuleGen 3.0. If you want to try out RuleGen yourself, you can download the framework under trial conditions from http://www.rulegen.com/free-download .
This article illustrates the essential steps in the business rule design and build process:
- describe the business in human readable format – preferably using names of entities and attributes or even better tables and columns
- analyze the events that potentially violate the business rule and should therefore trigger evaluation of the rule
- define the filter condition (a SQL expression) that identifies the records that should be checked for each triggering event (typically only a very small subset of the records in a table need to be explicitly validated upon an event)
- define the rule validation logic in terms of SQL – write the SQL query More >
RuleGen 3.0 – the latest, leanest and most robust solution for complex data constraints in an Oracle Database
0No matter how complex the enterprise and application architectures become, no matter the number of tiers, services, devices and user interfaces – at the heart of most enterprises will be a relational database.
And no matter how hard we try to implement a fully service based architecture or a multi-purpose business tier (for example using EJBs) – we will have multiple routes to the database and the data in it. Data will be manipulated through web applications, web services, client/server applications, batch database jobs, application managers working directly against the database from the command line or TOAD-like tools. If for no other reason – that by itself is an overridding motivation for enforcing every data constraint at the lowest possible level – the one level that none of these channels can avoid: the database itself. In addition to the fact that only enforcement inside the database can provide real integrity (and what the hack would be semi-real integrity?), for most data rules (especially complex ones) implementation inside the database is the most performant, scalable, maintainable, managable, agile, elegant and easy to implement as well.
Note: I am not advocating that More >
Tracking the moving history of averages and other aggregates – Flashback Aggregates in Oracle SQL
0You may have seen we write on Flashback functionality in the Oracle Database. It’s an area that I like – especially since the introduction of the Flashback Data Archive in Oracle 11g. As an application developer, I typically focus on Flashback Query (AS OF) and Flashback Versions query (VERSIONS BETWEEN …). The latter provides an overview of the entire history of records in a table (in so far the UNDO area or the Flashback Data Archive has the information available). The former allows us to query an entire table at a certain moment in the past.
This article looks at a combination of the two. Take the following situation – using table EMP once more as our sample set: once upon a time, all employees in Department 10 see their salary increased by 15%. The next month, all CLERKs are made happy with a $200 pay raise. Two months later, MANAGERs are cut back – salary decrease of 10%. And finally, in this brief history of time, everyone hired in 1981 is awarded 150 extra in their regular paycheck.
Using Flashback Versions query, we can find out for every employee what the various salary levels are that they have been at. And we could create a chart with the line of salary levels plotted More >
Recent Comments