This is the second blog post of a series on using Oracle Text, Oracle R Enterprise and Oracle Data Mining. Check out the first blog post of the series , as the data used in this blog post was extracted, processed and stored in a databases table. In this blog post I will show you how you use Oracle R Enterprise and the embedded R execution features of ORE to use the text from the webpages and to create a word cloud. This is a useful tool to be able to see visually what words can stand out most on your webpage and if the correct message is being put across to your customers. Prerequisites: You will need to load the following R packages into your R environment 'tm', 'word cloud' 'SnowballC'. These are required to process the following R code segments. install.packages (c( "tm", "wordcloud", "SnowballC")) library (tm) library (wordcloud) library (SnowballC) Select data from table and prepare: We need to select the data from the table in our schema and to merge it into one variable. local_data tm_data for(i in 1:nrow(local_data)) { tm_data } tm_data Create function to perform Text Mining: In my previous blog post on creating a word cloud I gave the R code. In order to allow for this R code to be run on the database server (using the embedded R execution of ORE) we need to package this text mining R code up into a ORE user defined R script. This is stored in the database. ore.scriptDrop("prepare_tm_data") ore.scriptCreate("prepare_tm_data", function (tm_data) { library(tm) library(SnowballC) library(wordcloud) txt_corpus Before we can run this user define R script, we need to ensure that we have the 'tm', 'SnowballC' and 'wordcloud' R packages installed on the Oracle Database server. On the Oracle Database server you need to rune ORE. ORE Then run the following command to install these R packages > install_packages(c('tm','wordcloud', 'SnowballC')) Run the function on the DB Server: You are now ready to run the function. In an earlier step we had gathered the data. Now we can pass this data to the in-database R script. > res The ore.doEval function is a general purpose ORE function. In this case we pass it two parameters. The first parameter is the neame of the user defined R script stored in the database, and the second parameter is the data. The function returns and ORE object that contains the word cloud graphic. Display the results: You can very easily display the results. > res This gives us the following graphic. In my next blog post, of this series, I will show you how you can use the function created above and some other bits and pieces, using some other features of ORE and also in SQL.
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