1.1 KiB
1.1 KiB
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SQL Update Statement |
SQL Update Statement
To update a record in a table you use the UPDATE
statement.
Be careful. You can update all records of the table or just a few. Use the WHERE
condition to specify which records do you want to update. It is possible to update one or more columns at a time. The syntax is:
UPDATE table_name
SET column1 = value1,
column2 = value2, ...
WHERE condition;
Here is an example updating the Name of the record with Id 4:
UPDATE Person
SET Name = “Elton John”
WHERE Id = 4;
You can also update columns in a table by using values from other tables. Use JOIN
clause to get data from multiple tables. The syntax is:
UPDATE table_name1
SET table_name1.column1 = table_name2.columnA
table_name1.column2 = table_name2.columnB
FROM table_name1
JOIN table_name2 ON table_name1.ForeignKey = table_name2.Key
Here is an example updating Manager of all records:
UPDATE Person
SET Person.Manager = Department.Manager
FROM Person
JOIN Department ON Person.DepartmentID = Department.ID