title: Database lookup in Talend
body: <p>In my talned job I am copying data from Excel to SQL table.
  For this job to maintain the foreign key constraint I had to do a look up before copying the data.</p>
  
  <p>The task goes like this.
  I have to copy data in Table2 (id keys value).
  My excel sheet has data for id and keys column. Table 1 has two columns id and value.</p>
  
  <p>For value column's data I want to look at Table1's corresponding entry with the id of the current record in Table2. I have to copy the data from Table1's value column to Table2's value column.</p>
  
  <p>Excel (id 1 2 3, keys a b c)
  Table_1 (id 1 2 3, value 123 456 789)
  desired output: Table_2 (id 1 2 3, keys a b c, value 123 456 789)
  current output: Table_2 (id 1 2 3, keys a b c, value null null null)</p>
  
  <p>How do I properly map this?</p>
  
  <p><img src="https://i.stack.imgur.com/fgkiB.png" alt="enter image description here">
  <img src="https://i.stack.imgur.com/yVh2z.png" alt="enter image description here"></p>