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Not able to join multiple table using multiple ELT tMap components

Hi,
We are joining two tables by using ELT tMap component and bringing this output to join it further with another table in database by using another ELT tMap. Though the job is created without any errors, but the resulting insert query for the output table as defined in the output component is displaying the alias for the second tMap component instead of the full query for the first table joins. This makes Talend to search for the second tMap alias as the table name which it couldn't find in the database. Is this some kind of bug in the ELT tMap component?
If no, can anyone help us with some solution for this?
7 REPLIES
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Re: Not able to join multiple table using multiple ELT tMap components

Are you using two tELT<db>Maps in one subJob? My experience so far is that will not work. I would be interested to hear if someone has make this happen.
Can you do all of your joins in a single tELT<db>Map?
If not, what I do is create a temporary table as the output of the first tELT<db>Map and use the temporary table as the input to the second tELT<db>Map.
I don't know if it matters, but what database vendor are you using?
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Re: Not able to join multiple table using multiple ELT tMap components

Can you post a picture of the tMaps and job so we can identify the problem.
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Re: Not able to join multiple table using multiple ELT tMap components

Thanks for the replies!
Mike's solution of creating a temporary table works, but here we would want multiple joins, so to have our job look readable & not look messy, we need to have more than 2 tELT<db>Map components. But the final job query takes into consideration the select query of the last tELT<db>Map that connects to the output component and ignores the earlier ones created in each tELT<db>Map. That means our approach of taking multiple tELT<db>Maps won't work.
However, we can implement these many joins using a single tELT<db>Map component but going this way:
> Our job will look messy.
> Debugging any kind of join errors or errors related will be very difficult.
Is there any other way(ELT template components/others) we can implement joins on multiple tables?

Apologizing for not able to post any related snaps as there is no option for it.
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Re: Not able to join multiple table using multiple ELT tMap components

Click on Post Reply and do an image upload.
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Re: Not able to join multiple table using multiple ELT tMap components

I agree it is messy, but I always prefer to use one tELTmap component over many.
- usually performs better than multiple tELTmaps
- do not need to wonder which tELTmap has the logic you need to find or modify.
It would be nice if you could chain them together like a tMap.
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Re: Not able to join multiple table using multiple ELT tMap components

Hi,
Can any one help me on this pls.
I have table 1 with 10 columns and table 2 with 5 columns. I want to join these 2 tables based on one column and get all 10+5 columns (from both tables) as out put after the condition is matched.
How I can do this in Talened. I tried to use tjoin, but I am not able to get the lookup columns into my out put.
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Re: Not able to join multiple table using multiple ELT tMap components

got it..