How to update table value based on another table

Question

I have a table called Product and its data and table structure something like as follows,

+-----------+-------------+-----------+
| ProductId | ProductName | SortValue |
+-----------+-------------+-----------+
| 1157      | ABC         | 7         |
+-----------+-------------+-----------+
| 1156      | DEF         | 3         |
+-----------+-------------+-----------+
| 1155      | GHI         | 4         |
+-----------+-------------+-----------+
| 1154      | JKL         | 2         |
+-----------+-------------+-----------+
| 1153      | MNO         | 1         |
+-----------+-------------+-----------+
| 1152      | PQR         | 5         |
+-----------+-------------+-----------+
| 1151      | STU         | 6         |
+-----------+-------------+-----------+

I have another table called LocationProdut which is the reference product table and location table, for each location productid has its own sort value.sample data and table structure its as follows,

+--------------+-------------+-----------+
| fkLocationId | fkProductId | Sortvalue |
+--------------+-------------+-----------+
| 19           | 1157        | 1         |
+--------------+-------------+-----------+
| 19           | 1156        | 2         |
+--------------+-------------+-----------+
| 19           | 1155        | 3         |
+--------------+-------------+-----------+
| 19           | 1154        | 4         |
+--------------+-------------+-----------+
| 19           | 1153        | 5         |
+--------------+-------------+-----------+
| 19           | 1152        | 6         |
+--------------+-------------+-----------+
| 19           | 1151        | 7         |
+--------------+-------------+-----------+
| 20           | 1155        | 3         |
+--------------+-------------+-----------+
| 20           | 1154        | 4         |
+--------------+-------------+-----------+
| 20           | 1153        | 5         |
+--------------+-------------+-----------+
| 20           | 1152        | 6         |
+--------------+-------------+-----------+
| 20           | 1151        | 7         |
+--------------+-------------+-----------+
| 21           | 1155        | 3         |
+--------------+-------------+-----------+
| 21           | 1154        | 4         |
+--------------+-------------+-----------+
| 21           | 1153        | 5         |
+--------------+-------------+-----------+
| 21           | 1152        | 6         |
+--------------+-------------+-----------+
| 21           | 1151        | 7         |
+--------------+-------------+-----------+

Now I need to update SortValue coulmn in LocationProdut table, in order to Product table's SortValue for only fkLocationId = 19 & 20

Expected output as follows.

+------------+-------------+-----------+
| fkBranchId | fkServiceId | Sortvalue |
+------------+-------------+-----------+
| 19         | 1157        | 7         |
+------------+-------------+-----------+
| 19         | 1156        | 3         |
+------------+-------------+-----------+
| 19         | 1155        | 4         |
+------------+-------------+-----------+
| 19         | 1154        | 2         |
+------------+-------------+-----------+
| 19         | 1153        | 1         |
+------------+-------------+-----------+
| 19         | 1152        | 5         |
+------------+-------------+-----------+
| 19         | 1151        | 6         |
+------------+-------------+-----------+
| 20         | 1155        | 4         |
+------------+-------------+-----------+
| 20         | 1154        | 2         |
+------------+-------------+-----------+
| 20         | 1153        | 1         |
+------------+-------------+-----------+
| 20         | 1152        | 5         |
+------------+-------------+-----------+
| 20         | 1151        | 6         |
+------------+-------------+-----------+
| 21         | 1155        | 3         |
+------------+-------------+-----------+
| 21         | 1154        | 4         |
+------------+-------------+-----------+
| 21         | 1153        | 5         |
+------------+-------------+-----------+
| 21         | 1152        | 6         |
+------------+-------------+-----------+
| 21         | 1151        | 7         |
+------------+-------------+-----------+

Answer 1

You could use a simple inner join to update the required rows:

UPDATE LP
  SET 
      LP.Sortvalue = P.SortValue
FROM LocationProduct LP
JOIN Product P ON LP.fkProductId = P.ProductId
WHERE fkLocationId IN(19, 20);

Please find the db<>fiddle here .

Answer 2

UPDATE        targetTable
SET           targetTable.targetColumn = s.sourceColumn
FROM          targetTable t
INNER JOIN    sourceTable s
ON            t.matchingColumn = s.matchingColumn