![]() ![]() Public void doGet(HttpServletRequest request, HttpServletResponse response) The image servlet that I created is also based on the example by Timo Hahn, and the doGet() method is defined as follows: I will not show exactly how I did this here, as the why-and-how of this has been well described by others, such as Timo Hahn: More in line with the ADF framework though, would be to use the existing binding layer of the framework. Several strategies can be followed, such as defining a prepared statement within the image servlet class itself, or creating and releasing a root application module ‘on the fly’. A large amount of blogs/tutorials have been devoted to this subject. To eventually show/render this Blob as an image in the browser, we need to create an image-servlet. Now if we create an application module containing this view object and run the Business Component tester, we can see that this indeed gives us a proper result (although we still have to await how the graph looks of course): The datatype of the image-attribute is set to BlobDomain. A SQL-type bind variable BParam is defined as well, so that the number of plotted point can be manipulated by changing the parameter value. I then created a model project, with a custom SQL-query-based view object using the earlier described SELECT statement. With port forwarding, I used my local JDeveloper (12c) to set up the connection with the database on the virtual machine. In my case, I took the easy way and used the 12c Big Data Lite VM provided by Oracle. Of course we need a connection to a properly configured database. So, having our script ready to be executed, let’s switch to our ADF application. The third argument specifies the format of the result, and the last argument the name of the script to be executed. The second argument is an optional parameter-cursor, in this case NULL. The first argument is a cursor with input data for the function defined in the RndDotsPlots script, where the bind variable represents the param-argument. The rqTableEval function is one of several functions provided by the SQL interface (again, for more information see the tutorial provided by Oracle). So I tried out a couple of things, resulting in this blogpost in which I will show a very basic example of using Embedded R Execution in an ADF application. is given in a tutorial series on Oracle R Enterprise v 1.4 in the Oracle Learning Library:īeing an ADF-developer myself, going through this tutorial series made me wonder : what are the possibilities of integrating R, or more specifically, Embedded R Execution within an ADF application ? For example, the graphical facilities of R could surely add some useful functionality to a typical ADF database application. A very nice introduction to these technologies, features etc. To support this feature, both an R- and a SQL- interface is provided. Embedded R ExecutionĪn interesting feature of ORE is the possibility of Embedded R Execution, which facilitates embedded R script execution on the database server machine. Oracle has also recognized this development and defined a strategy for supporting open-source R, resulting in new interesting technologies, such as Oracle R Enterprise (ORE, part of the Advanced Analytics option in Oracle DB 12c en 11g) and ROracle, an open-source Oracle database interface for R. Nowadays, R is gaining popularity at a rapid pace, within several domains, including that of Big Data. While doing so, I spent quite some time programming in R, an open statistical programming language with a wide range of possibilities for statistical computing and data visualization. Before I came involved in software development, I used to work as a statistical researcher. ![]()
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