How to modify a certain row in mysql
The syntax for modifying a row of data in MySQL is: UPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition;. Among them, condition is used to uniquely identify the row to be modified, and value1, value2... are the new column values. Be careful to make sure that condition specifies a unique identifier, otherwise multiple rows may be accidentally updated. Verify changes using the SELECT statement.
How to modify a row in MySQL
The syntax for modifying a row of data in MySQL is as follows:
<code>UPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition;</code>
Where:
-
table_name
is the name of the table to be updated. -
column1
,column2
, ... are the column names to be updated. -
value1
,value2
, ... are the new values. -
condition
is the condition used to determine the row to be updated.
Usage Example
The following example updates the of the row with
id being 5 in the
users table name
and email
columns:
<code>UPDATE users SET name = 'John Doe', email = 'johndoe@example.com' WHERE id = 5;</code>
Notes
- Make sure
condition
specifies a unique identifier character to avoid accidentally updating multiple rows. - If
condition
is not satisfied for any row, no data will be updated. - If the specified value violates a constraint (for example, a primary key or a non-null column), an error is raised.
- After updating a row, you can use the
SELECT
statement to verify the changes.
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