I want to achieve basic SQL join to create a collection
Select t.EMPID, t.EmployeeName, M.Skills
from tabcollection t, Merge4collect M
where t.EMPID0=M.field_1

I want to achieve basic SQL join to create a collection
Select t.EMPID, t.EmployeeName, M.Skills
from tabcollection t, Merge4collect M
where t.EMPID0=M.field_1
ForAll(RenameColumns(Collection1,"User","User1","dept","dept1"),UpdateIf(Collection2,Title = User1,{dept:dept1}))
This should definitely work.
Taken from Solved: Join two collections - Power Platform Community (microsoft.com)
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