In one of my previous blog articles called ´´Deduplication using Analytic Function´´, I explained a simple introduction of Oracle Analytic Functions. In this article (addressed for SQL developers), I will focus on the LAG function which from my point of view, is one of the most useful functions. Let’s see the use of this function in a common Data Warehouse scenario: Slowly Changing Dimension. Continue reading this post >
Lookups are expensive in terms of resources and time.
A set of tips about how to setup lookup transformations would dramatically improve the main constrains such as time and performance.
In this article you will learn about the following topics:
- Lookup cache
- Persistent lookup cache
- Unconnected lookup
- Order by clause within SQL
Informatica Deployment Groups, simply put, act as containers that allow smart grouping of objects to facilitate the deployment between different folders, repositories and environments.
They are objects themselves and they contain specific versioned objects selected for deployment from different source folders.
Informatica Deployment Groups can contain folders, mappings, mapplets, reusable transformations, sources, targets, workflows, sessions and tasks and can help transfer these objects into multiple folders across repositories in different domains. The objects contained within a Deployment Group are versioned so the recipient repository will have to be versioned too.
Informatica Power Center can use different sources of data. The most common sources are tables, views or synonyms, but for storing small sets of data, companies usually use flat files, MS Excel files or MS Access. Informatica treat Excel and Access file sources as a relational database, not as a flat file.
Which steps do we have to follow to load this data from these files to our Data Warehouse? How are the connections created? Where do these files have to be located? How should we configure Informatica?
In this article I will explain the way to load data from Excel files using Informatica Power Center running on Windows.
GoldenGate is a tool that Oracle acquired in 2009 that allows us to capture, route, transform and send data between heterogeneous systems in real time with a very low impact on the source systems.
So basically Oracle GoldenGate (OGG from now on) moves data between point A and point B, but it does it in a brilliant way. Let’s take a look in detail to its main features:
Very low impact on data sources – This means that OGG does not disturb the source systems when fetching new data. In order to achieve that it doesn’t really access the database layer but it’s constantly looking for change in the redo files (or equivalent technology) to know when a transaction has been done.
Heterogeneous Systems – Thanks to the ODBC technology and the VAM (Vendor Access Modules) OGG is able to interconnect a nice amount of database vendors between each other, although only the ones that offers referential integrity can be chosen as source systems.
Real time – Maybe you’ve heard that OGG can transfer data with a sub second latency. That is true if your integration scenario meets some conditions and the physical distance between source and destination is not huge. Anyway, in the worst circumstances we are talking about real low latency times.
