Issue with Merge Node: Unable to Filter Non-Matching Items Between Input1 and Input2 Dear n8n Team,

[Wskey]

Subject: Issue with Merge Node: Unable to Filter Non-Matching Items Between Input1 and Input2

Dear n8n Team,

I hope this message finds you well.

I am reaching out to report an issue I’ve encountered while using the Merge node in n8n. Specifically, I’m trying to filter out items present in Input1 that are not present in Input2, but the expected results are not being achieved.

Scenario:

• Input1: Contains 200 user records.
• Input2: Contains 190 user records, which are a subset of Input1 (i.e., Input1 minus 10 records).
• Objective: Identify and extract the 10 records in Input1 that are not present in Input2.

Approaches Tried:

1. Combine Mode:

   • Combination By: Matching Fields
   • Fields to Match: order_code (serves as the primary key)
   • Output Type: Keep Non-Matches
   • Output Data From: Input1

   Despite configuring the node as per the documentation, the Merge node does not return the 10 unmatched records as expected.
   

   

2. SQL Query Mode:

   • Number of Inputs: 2
   • Query Used:

     SELECT input1.*
     FROM input1
     LEFT JOIN input2 ON input1.order_code = input2.order_code
     WHERE input2.order_code IS NULL
     

   This query also fails to return the desired 10 records that are exclusive to Input1.
   

   

Additional Information:

• Both Input1 and Input2 have identical field names and data types.
• The order_code field is consistent in both inputs and is used as the matching key.
• I have ensured that there are no discrepancies in data formatting or types that could affect the matching process.

I would appreciate any guidance or insights you can provide to help resolve this issue. If there’s a recommended approach or if this is a known limitation, please let me know.

Thank you for your time and assistance.

Best regards,

[Wskey]