Update Data In a Database
The UPDATE statement is used to update existing records in a table.
Syntax
UPDATE table_name
SET column1=value, column2=value2,…
WHERE some_column=some_value
SET column1=value, column2=value2,…
WHERE some_column=some_value
Note: Notice the WHERE clause in the UPDATE syntax. The WHERE clause specifies which record or records that should be updated. If you omit the WHERE clause, all records will be updated!
To get PHP to execute the statement above we must use the mysqli_query() function. This function is used to send a query or command to a MySQL connection.
Example
Earlier in the tutorial we created a table named “Persons”. Here is how it looks:
| FirstName | LastName | Age |
|---|---|---|
| Peter | Griffin | 35 |
| Glenn | Quagmire | 33 |
The following example updates some data in the “Persons” table:
<?php
$con=mysqli_connect(“example.com”,”peter”,”abc123″,”my_db”);
// Check connection
if (mysqli_connect_errno())
{
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}
$con=mysqli_connect(“example.com”,”peter”,”abc123″,”my_db”);
// Check connection
if (mysqli_connect_errno())
{
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}
mysqli_query($con,”UPDATE Persons SET Age=36
WHERE FirstName=’Peter’ AND LastName=’Griffin'”);
mysqli_close($con);
?>
After the update, the “Persons” table will look like this:
| FirstName | LastName | Age |
|---|---|---|
| Peter | Griffin | 36 |
| Glenn | Quagmire | 33 |
