Conditional row update

Hi smpa01 ,

1.Create a temporary table with the updated values:

let tempTable = datatable (id:int, name:string, city:string, salary:int, tel:string)
[
    1, 'sam', 'london', 1000, null,
    2, 'john', 'ny', 2000, null
];

2.Merge the temporary table with the original table:

let emp = datatable (id:int, name:string, city:string, salary:int, tel:string)
[
    1, 'sam', '', '', '',
    2, 'john', '', '', '',
    3, 'tom', '', '', ''
];

let updatedEmp = union emp, tempTable
| summarize city = any(city), salary = any(salary), tel = any(tel) by id, name;

.set-or-replace emp <| updatedEmp

This approach allows you to selectively update specific columns without needing to provide values for the entire row. 

Best Regards,

Neeko Tang

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