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  1. Open the Hive Shell: Open the Hive shell so you can manually create a Hive table by entering 'hive' at the command line.

  2. Create the Table in Hive: You need a hive table to load the data to, so enter the following in the hive shell.
    Code Block
    create table weblogs (
        client_ip    string,
        full_request_date string,
        day    string,
        month    string,
        month_num int,
        year    string,
        hour    string,
        minute    string,
        second    string,
        timezone    string,
        http_verb    string,
        uri    string,
        http_status_code    string,
        bytes_returned        string,
        referrer        string,
        user_agent    string)
    row format delimited
    fields terminated by '\t';
    
  3. Close the Hive Shell: You are done with the Hive Shell for now, so close it by entering 'quit;' in the Hive Shell.

  4. Load the Table: Load the Hive table by running the following commands:
    Code Block
    hadoop fs –cp /weblogs/parse/part-00000 /user/hive/warehouse/weblogs/
    
    

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Include Page
Create

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Hive

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Database Connection

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Create

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Hive

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Database Connection

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Create a

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  1. Connection Name: Enter 'Hive'
  2. Connection Type: Select 'Hadoop Hive'
  3. Host Name and Port Number: Your connection information. For local single node clusters use 'localhost' and port '10000'.
  4. Database Name: Enter 'Default'
    When you are done your window should look like:
    Image Removed
    Click 'Test' to test the connection.
    If the test is successful click 'OK' to close the Database Connection window.

Create a Job to Aggregate Web Log Data into a Hive Table

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Tip
titleSpeed Tip

You can download the Kettle Job ^aggregate aggregate_hive.kjb already completed

  1. Start PDI on your desktop. Once it is running choose 'File' -> 'New' -> 'Job' from the menu system or click on the 'New file' icon on the toolbar and choose the 'Job' option.

  2. Add a Start Job Entry: You need to tell PDI where to start the job, so expand the 'General' section of the Design palette and drag a 'Start' node onto the job canvas. Your canvas should look like:


  3. Add a SQL Job Entry: You are going to run a HiveQL script to create the aggregate table, so expand the 'Scripting' section of the Design palette and drag a 'SQL' node onto the job canvas. Your canvas should look like:


  4. Connect the Start and SQL Job Entries: Hover the mouse over the 'Start' node and a tooltip will appear. Click on the output connector (the green arrow pointing to the right) and drag a connector arrow to the 'SQL' node. Your canvas should look like this:


  5. Edit the SQL Job Entry: Double-click on the 'SQL' node to edit its properties. Enter this information:
    1. Connection: Select 'Hive'
    2. SQL Script: Enter the following
      Code Block
      create table weblogs_agg
      as
      select
        client_ip
      , year
      , month
      , month_num
      , count(*) as pageviews
      from weblogs
      group by   client_ip, year, month, month_num
      
      When you are done your window should look like:

      Click 'OK' to close the window.

  6. Save the Job: Choose 'File' -> 'Save as...' from the menu system. Save the transformation as 'aggregate_hive.kjb' into a folder of your choice.

  7. Run the Job: Choose 'Action' -> 'Run' from the menu system or click on the green run button on the job toolbar. A 'Execute a job' window will open. Click on the 'Launch' button. An 'Execution Results' panel will open at the bottom of the PDI window and it will show you the progress of the job as it runs. After a few seconds the job should finish successfully:
    If any errors occurred the job step that failed will be highlighted in red and you can use the 'Logging' tab to view error messages.

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  1. Open the Hive Shell: Open the Hive shell so you can manually create a Hive table by entering 'hive' at the command line.
  2. Query Hive for Data: Verify the data has been loaded to Hive by querying the weblogs table.
    Code Block
    select * from weblogs_agg limit 10;
    
    


  3. Close the Hive Shell: You are done with the Hive Shell for now, so close it by entering 'quit;' in the Hive Shell.

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During this guide you learned how to transform data within Hive within a PDI job flow.

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