The UPDATE statement is used to update existing records in a table.
SQL UPDATE Syntax
UPDATE table_name
SET column1=value1,column2=value2,...
WHERE some_column=some_value;
SET column1=value1,column2=value2,...
WHERE some_column=some_value;
SQL UPDATE Example
Assume we wish to update the customer "Alfreds Futterkiste" with a new contact person and city.
We use the following SQL statement:
Example
UPDATE Customers
SET ContactName='Alfred Schmidt', City='Hamburg'
WHERE CustomerName='Alfreds Futterkiste';
SET ContactName='Alfred Schmidt', City='Hamburg'
WHERE CustomerName='Alfreds Futterkiste';
 | Notice the WHERE clause in the SQL UPDATE statement! The WHERE clause specifies which record or records that should be updated. If you omit the WHERE clause, all records will be updated! |
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