Using Hadoop to Create SOLR Indexes

One of the most challenging projects I faced at work recently was to create a Apache SOLR index consisting of approx 15 million records. This index had been created once in the history of the company using a MySQL database and SOLR’s Data Import Handler (DIH). It had not been attempted since then because the original indexing process was time consuming (12-14 hours), required human supervision, and on failure had to be restarted from the very beginning.
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r cannot be resolved

In the Google group Android Beginners I frequently see messages that ask what the error "r cannot be resolved" means in Eclipse.

Eclipse generates the file R.java for you using the aapt tool (Official Guide to the Android Asset Packaging Tool). R.java contains a mapping to all the resources your application will use. Note that you should have the Build Automatically option under the Project menu checked on.
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OutOfMemoryException in Maven

I came across a situation today where Maven threw an OutOfMemoryException. I didn’t think the process would have taken that much memory but it clearly did. I was trying to deploy. I then tried it again but skipped the tests. No good. I found out that by setting the MAVEN_OPTS environment variable to something like -Xmx512m I was good to go.