title: Update column in HIVE
body: <p>I have a table in php which is in this format:</p>
  
  <p>CREATE EXTERNAL TABLE  IF NOT EXISTS {$tableName} (fileContent VARCHAR(250), description VARCHAR(250), dimension DOUBLE, fileName VARCHAR(250)) ROW FORMAT
  DELIMITED FIELDS TERMINATED BY ','
  LINES TERMINATED BY '\n' 
  STORED AS TEXTFILE
  LOCATION '/var/www/ASOIS_Proiect/metadata/'</p>
  
  <p>I want for a situation to update only description field if fileName='a' and 'size'='12' already exist in database.</p>
  
  <p>Any idea please? I tried to update the file create for insert with command LOAD and flag OVERWRITE but it is not working.</p>