Here is a sample code
CREATE TABLE #Table1
(
Uid INT,
UName VARCHAR(50),
Phone VARCHAR(50)
)
INSERT INTO #Table1
SELECT NULL, 'ABC1', '12345' UNION ALL
SELECT NULL, 'EFG1', '67890' UNION ALL
SELECT NULL, 'JKL1', '13567' UNION ALL
SELECT NULL, 'MNO1', '24680' UNION ALL
SELECT NULL, 'QWS1', '67981'
--Before Updating Uid
SELECT * FROM #Table1;
WITH CTE AS
(
SELECT ROW_NUMBER() oVER (ORDER BY UName) + 100 AS Id, * FROM #Table1
)
UPDATE T
SET UId = Id
FROM #Table1 T
INNER JOIN CTE ON T.UName = CTE.UName AND T.Phone = CTE.Phone
--Afer Updating Uid
SELECT * FROM #Table1
DROP TABLE #Table1