title: Pig script filter a file getting ERROR
body: <p>I am new to pig. I'm trying to filter the text file and store it in hbase. Here is the sample input file</p>
  
  <p><strong>sample.txt</strong></p>
  
  <pre><code>{"pattern":"google_1473491793_265244074740","tweets":[{"tweet::created_at":"18:47:31 ","tweet::id":"252479809098223616","tweet::user_id":"450990391","tweet::text":"rt @joey7barton: ..give a google about whether the americans wins a ryder cup. i mean surely he has slightly more important matters. #fami ..."}]}
  {"pattern":"facebook_1473491793_265244074740","tweets":[{"tweet::created_at":"11:33:16 ","tweet::id":"252370526411051008","tweet::user_id":"845912316","tweet::text":"@maarionymcmb facebook mere ta dit tu va resté chez toi dnc tu restes !"}]}
  </code></pre>
  
  <p><strong>Script:</strong></p>
  
  <pre><code>data = load 'sample.txt' using JsonLoader('pattern:chararray, tweets:  bag {t1:tuple(tweet::created_at: chararray,tweet::id: chararray,tweet::user_id: chararray,tweet::text: chararray)}');
  A = FILTER data BY pattern == 'google_*';
  grouped = foreach (group A by pattern){tweets1 = foreach data generate tweets.(created_at),tweets.(id),tweets.(user_id),tweets.(text); generate group as pattern1,tweets1;}
  </code></pre>
  
  <p>But I got this error when run grouped:</p>
  
  <pre><code>2016-09-10 13:38:52,995 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1200: Pig script failed to parse: &lt;line 41, column 57&gt; expression is not a project expression: (Name: ScalarExpression) Type: null Uid: null)
  </code></pre>