Set/change Workspace default location

To set this workspace location, edit "config.ini" file in "configuration" folder at root of Talend installation folder.
In this file you can use variable "osgi.instance.area" or "osgi.instance.area.default" to specify your workspace location.
Follow below steps to complete this activity.

Step 1. Go to the Talend Installed directory then configuration folder like C:\Talend\TOS_DI-Win32-........\configuration.

Step 2. Open config.ini file.

Step 3. Write down below code at first line of file.

osgi.instance.area=provide your workspace path.

e.g.

osgi.instance.area=C:/Talend/TOS_DI-Win32...../workspace

Step 4. Save config.ini file keep open.

Step 5. Restart Talend, once you see first window then remove above line of code, save and close the config.ini file.

 

How to redirect standard output to a file

Many times you need to get log details on external files which Talend is not able to redirect or catch using standard Log management, but you know many times error displays on Talend run console but is not caught in error connector. so here is sample code which you can use in your job to redirect error or run console messages to file.

just at the beginning of you job place tJava, and inside a tjava, redirect globally the standard output... insert this code (add buffering if you need):

-------------------------
java.io.File file = new java.io.File("C:/data/mylogfile_test.txt");
java.io.PrintStream ps = new java.io.PrintStream(new java.io.FileOutputStream(file));
System.setErr(ps);
System.setOut(ps);
-------------------------

JobScript Step by Step 1 - What is Job Script

JobScript is simple text file with .jobscript extension, this file is used by Talend API  to generate Talend Job, in JobScript you can define components, schema, transformations, connections between component. and all the things which can be done using Talend Job designer.

Note: JobScript feature not available in Talend Open Studio. 

JobScript looks like a plain Text having JSON like structure. if you aware of Json then it is very easy to understand JobScript. Talend help center has good explanation on JobScript check once so you have good understanding of JobScript and the terminology we will use.

We will create job script to create a job which will be used for loading CSV data to SQL server with transformations.
so our job will have following components.

• tFileInputDelimited


• tMap


• tMSSQLOutput

below screen you can see a sample JobScript which has exact hierarchy which start with basic setting of job then job parameters, components , and ends with component connections. I have marked those in numbers with block so there are total 3 blocks which i am going explain in detail.

Create Talend JobScript Step by Step

Talend is great code generator having 200+ connectors,  which gives you ability to transform data from one system to another. Talend is good for mid size organisation where you have to process few MB of data not GB`s and TB`s of data. because having lack of parallel processing, generic schema load model and batch processing features. there are some component and feature available which Talend claims it will give you parallel and batch processing but it fails at certain level. any way we are not going to discuss Talend perhaps we will discuss how can we automate Talend Job creation? instead creating hundreds of jobs for hundreds of metadata?

I am ETL developer and i have been assigned task to create one such job which will be used like generic data loader where metadata will be stored in SQL database tables, and these tables will be used by my job to create schema, apply transformations and then load the SQL, is short Dynamic schema using Talend.

I thought it`s great idea and Talend has Dynamic schema feature, then it can be done in few days. but when i started working on it became nightmare, so finally i dropped the idea of Dynamic schema. because of following reason.

• Reject Connectore will not work.


• You can not apply custom transformations during load


• You have to apply transformation using SQL.


• Your file must have header row.


• All the fields loaded with string data type.


• You have to change data type at the SQL side.


• No escape character support.


• SQL Table must present before start the load.


• Log management will not work.

I communicated with Talend using help center, Talend Forged and after so long found solution which is not Dynamic Schema but Dynamic Job creation using JobScript.  Yes JobScript , it is Json like structure  with nodes and child nodes, properties with values, components and settings, connections, context, routines and many more. every can be define using JobScript.

In next post i will explain what  JobScript exactly, it basic structure and basic things need to create JobScript.

Syntax error on tokens, delete these tokens

You may face this error when start development using Talend, once you get hands on with Talend  this type of errors will be disappeared because, this error comes whenever you do typo mistakes or any configuration during populating schema from one component to another. if you follow simple steps in working environment you will not face this any more.

• All string which are set for any component must be closed with double quotes
  
  
  
  • File name and paths
  
  
  • line feed string
  
  
  • column separator
  
  
  • Host names
  
  
  • URL
  
  
  • Table name
  
  
  • Database name and many more
  
  
  
  


• if you are using schema for any component then make sure the same schema is assign to next components schema other wise it throw error.
  
  
  
  • tJavaRow is most popular component and many times it throws this error because schema is different than code generated column list.
  
  
  • variables are used instead of column names
  
  
  • if you create empty row in schema (with no column name)
  
  
  
  

if you follow these rules you will not this error again.

How to solve "GC overhead limit exceeded" error

As the names suggested Java try to remove unused object but fail, because it not able to handle so many object created by Talend code generator.  There's simply too much objects being created too fast, and the standard Java GC mechanism (on 1.6 at least) is not able to handle it.

This error may occur during compiling job or at running job, so we have two way to fix.

For Run-Time solution is

• Opne Run TAB


• click on Advance Tab


• dobule click on -Xmas and incrise the size upto GB eg. -Xmas2G or -Xmas-100M


• double click on -Xmax and incrise the size upto GB eg. -Xmas4G or -Xmas-200M

For runtime Error Configuration of jobs JVM parameters is different from studio jvm startup parameters

In run-time case, you have to add/customize the JVM parameters to your binary.ini file in <TIS Install> directory if you are using The .ini files affect the studio (including compilation of jobs) but not the running of jobs.
For the studio memory, if you run TOS_DI-win-x86_64.exe then you need to modify TOS_DI-win-x86_64.ini.

These two save your life from "GC overhead limit exceeded" error

NoClassDefFoundError: org/apache/commons/codec/binary/Base64

Some times you may face this error, but may not get the right answer so i though it is better to post with steps to over come this error.

This problem occurs at run-time not at compile time, first search commons-codec.jar file in your talend installed directory like TalendInstall\TOS_DI-Win32-r78327-V5.0.2\plugins\org.talend.designer.components.localprovider_5.0.2.r78327\components\tMDMBulkLoad

if commons-codec.jar file is not on above mention location then download if from  commons-codec.jar file and. now we have our jar file ready so follow the steps to add it to build path.

• click on Windows menu


• then click on Preferences


• search "ClassPath variables" at top left search text box.


• result will be come then click on ClassPath variables. new popup window will be appeared.


• Click on new button give name for your ClassPath variable, and then browse for commons-codec.jar and add it. 


• here on done click on OK button and closed all the windows.

see the below screen for more details.

[caption id="attachment_148" align="alignnone" width="300"] Talend Classpath Setting[/caption]