Date Slot allocation based on slot available and ETA Date

Hi hpares85 

You can create a query with below M code. I have attached the sample file at bottom for your reference. 

let
    Source = Table.NestedJoin(#"GOODS ETA TABLE", {"PLANNED WAREHOUSE"}, #"TIME SLOT TABLE", {"WAREHOUSE"}, "TIME SLOT TABLE", JoinKind.LeftOuter),
    #"Added Custom" = Table.AddColumn(Source, "Custom", each let __ETA = [ETA] in Table.FirstN(Table.Sort(Table.SelectRows([TIME SLOT TABLE], each [TIME SLOT] > __ETA), {{"TIME SLOT", Order.Ascending}}),1)),
    #"Removed Other Columns" = Table.SelectColumns(#"Added Custom",{"GOODS", "ETA", "Custom"}),
    #"Expanded Custom" = Table.ExpandTableColumn(#"Removed Other Columns", "Custom", {"TIME SLOT", "WAREHOUSE"}, {"TIME SLOT", "WAREHOUSE"}),
    #"Filtered Rows" = Table.SelectRows(#"Expanded Custom", each ([WAREHOUSE] <> null)),
    #"Reordered Columns" = Table.ReorderColumns(#"Filtered Rows",{"GOODS", "ETA", "WAREHOUSE", "TIME SLOT"})
in
    #"Reordered Columns"

Best Regards,
Community Support Team _ Jing
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