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Anonymous
Not applicable

UNION Function not working as expected

I have three tables in need to combine into one.  They have the same # of columns, same columns names, data types etc.  When I join table 1 & 2, using UNION, it works with no issues.  When I add table 3, I get the message "Each table argument of 'UNION' must have the same number of columns".   This is confusing as the tables are the same.  Any ideas on what I may be missing and where to look for the problem?

3 ACCEPTED SOLUTIONS
BeaBF
Super User
Super User

@Anonymous Hi! it can be a Data Type Mismatch. Check the data types of each column in Table 3 and ensure that they match exactly with those in Table 1 and Table 2.

 

BBF

View solution in original post

dharmendars007
Super User
Super User

Hello @Anonymous , 

 

Please check the number of columns and also the data types of each tables this could be the issue that is causing the problem.

 

If you find this helpful , please mark it as solution which will be helpful for others and Your Kudos/Likes are much appreciated!

 

Thank You

Dharmendar S

LinkedIN 

View solution in original post

Anonymous
Not applicable

Hi @Anonymous , hello dharmendars007  and BeaBF, thank you for your prompt reply!

 

As a supplement, you could also use Append Queries in power query:

vyajiewanmsft_0-1727241977690.png

Link: Append queries - Power Query | Microsoft Learn

 

Best regards,

Joyce

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

View solution in original post

3 REPLIES 3
Anonymous
Not applicable

Hi @Anonymous , hello dharmendars007  and BeaBF, thank you for your prompt reply!

 

As a supplement, you could also use Append Queries in power query:

vyajiewanmsft_0-1727241977690.png

Link: Append queries - Power Query | Microsoft Learn

 

Best regards,

Joyce

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

dharmendars007
Super User
Super User

Hello @Anonymous , 

 

Please check the number of columns and also the data types of each tables this could be the issue that is causing the problem.

 

If you find this helpful , please mark it as solution which will be helpful for others and Your Kudos/Likes are much appreciated!

 

Thank You

Dharmendar S

LinkedIN 

BeaBF
Super User
Super User

@Anonymous Hi! it can be a Data Type Mismatch. Check the data types of each column in Table 3 and ensure that they match exactly with those in Table 1 and Table 2.

 

BBF

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