Updating MySQL Table

MySQLi — Update Query

There may be a requirement where the existing data in a MySQL table needs to be modified. You can do so by using the SQL UPDATE command. This will modify any field value of any MySQL table.

Syntax

The following code block has a generic SQL syntax of the UPDATE command to modify the data in the MySQL table −

UPDATE table_name SET field1 = new-value1, field2 = new-value2 [WHERE Clause]

• You can update one or more field altogether.
• You can specify any condition using the WHERE clause.
• You can update the values in a single table at a time.

The WHERE clause is very useful when you want to update the selected rows in a table.

Updating Data from the Command Prompt

This will use the SQL UPDATE command with the WHERE clause to update the selected data in the MySQL table tutorials_tbl.

Example

The following example will update the tutorial_title field for a record having the tutorial_id as 3.

root@host# mysql -u root -p password; Enter password:******* mysql> use TUTORIALS; Database changed mysql> UPDATE tutorials_tbl → SET tutorial_title = 'Learning JAVA' → WHERE tutorial_id = 3; Query OK, 1 row affected (0.04 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql>

Updating Data Using a PHP Script

PHP uses mysqli query() or mysql_query() function to update records in a MySQL table. This function takes two parameters and returns TRUE on success or FALSE on failure.

Syntax

Required — SQL query to update records in a MySQL table.

Optional — Either the constant MYSQLI_USE_RESULT or MYSQLI_STORE_RESULT depending on the desired behavior. By default, MYSQLI_STORE_RESULT is used.

Example

Try the following example to update a record in a table −

Copy and paste the following example as mysql_example.php −

    ", $mysqli→connect_error); exit(); > printf('Connected successfully.
'); if ($mysqli→query('UPDATE tutorials_tbl set tutorial_title = "Learning Java" where tutorial_id = 4')) < printf("Table tutorials_tbl updated successfully.
"); > if ($mysqli→errno) < printf("Could not update table: %s
", $mysqli→error); > $sql = "SELECT tutorial_id, tutorial_title, tutorial_author, submission_date FROM tutorials_tbl"; $result = $mysqli→query($sql); if ($result→num_rows > 0) < while($row = $result→fetch_assoc()) < printf("Id: %s, Title: %s, Author: %s, Date: %d 
", $row["tutorial_id"], $row["tutorial_title"], $row["tutorial_author"], $row["submission_date"]); > > else < printf('No record found.
'); > mysqli_free_result($result); $mysqli→close(); ?>  

Output

Access the mysql_example.php deployed on apache web server and verify the output. Here we’ve entered multiple records in the table before running the select script.

Connected successfully. Table tutorials_tbl updated successfully. Id: 1, Title: MySQL Tutorial, Author: Mahesh, Date: 2021 Id: 2, Title: HTML Tutorial, Author: Mahesh, Date: 2021 Id: 3, Title: PHP Tutorial, Author: Mahesh, Date: 2021 Id: 4, Title: Learning Java, Author: Mahesh, Date: 2021 Id: 5, Title: Apache Tutorial, Author: Suresh, Date: 2021

Источник

PHP MySQL UPDATE Query

In this tutorial you’ll learn how to update the records in a MySQL table using PHP.

Updating Database Table Data

The UPDATE statement is used to change or modify the existing records in a database table. This statement is typically used in conjugation with the WHERE clause to apply the changes to only those records that matches specific criteria.

The basic syntax of the UPDATE statement can be given with:

Let’s make a SQL query using the UPDATE statement and WHERE clause, after that we will execute this query through passing it to the PHP mysqli_query() function to update the tables records. Consider the following persons table inside the demo database:

+----+------------+-----------+----------------------+ | id | first_name | last_name | email | +----+------------+-----------+----------------------+ | 1 | Peter | Parker | peterparker@mail.com | | 2 | John | Rambo | johnrambo@mail.com | | 3 | Clark | Kent | clarkkent@mail.com | | 4 | John | Carter | johncarter@mail.com | | 5 | Harry | Potter | harrypotter@mail.com | +----+------------+-----------+----------------------+

The PHP code in the following example will update the email address of a person in the persons table whose id is equal to 1.

Example

 // Attempt update query execution $sql = "UPDATE persons SET email='peterparker_new@mail.com' WHERE $sql)) < echo "Records were updated successfully."; >else < echo "ERROR: Could not able to execute $sql. " . mysqli_error($link); >// Close connection mysqli_close($link); ?>

connect_error); > // Attempt update query execution $sql = "UPDATE persons SET email='peterparker_new@mail.com' WHERE === true) < echo "Records were updated successfully."; >else< echo "ERROR: Could not able to execute $sql. " . $mysqli->error; > // Close connection $mysqli->close(); ?>

setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); > catch(PDOException $e)< die("ERROR: Could not connect. " . $e->getMessage()); > // Attempt update query execution try< $sql = "UPDATE persons SET email='peterparker_new@mail.com' WHERE $pdo->exec($sql); echo "Records were updated successfully."; > catch(PDOException $e)< die("ERROR: Could not able to execute $sql. " . $e->getMessage()); > // Close connection unset($pdo); ?>

After update the persons table will look something like this:

+----+------------+-----------+--------------------------+ | id | first_name | last_name | email | +----+------------+-----------+--------------------------+ | 1 | Peter | Parker | peterparker_new@mail.com | | 2 | John | Rambo | johnrambo@mail.com | | 3 | Clark | Kent | clarkkent@mail.com | | 4 | John | Carter | johncarter@mail.com | | 5 | Harry | Potter | harrypotter@mail.com | +----+------------+-----------+--------------------------+

Warning: The WHERE clause in the UPDATE statement specifies which record or records should be updated. If you omit the WHERE clause, all records will be updated.

Источник

PHP MySQL Update Data

The UPDATE statement is used to update existing records in a table:

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 learn more about SQL, please visit our SQL tutorial.

Let’s look at the «MyGuests» table:

id	firstname	lastname	email	reg_date
1	John	Doe	john@example.com	2014-10-22 14:26:15
2	Mary	Moe	mary@example.com	2014-10-23 10:22:30

The following examples update the record with in the «MyGuests» table:

Example (MySQLi Object-oriented)

$servername = «localhost»;
$username = «username»;
$password = «password»;
$dbname = «myDB»;

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) die(«Connection failed: » . $conn->connect_error);
>

$sql = «UPDATE MyGuests SET lastname=’Doe’ WHERE ($conn->query($sql) === TRUE) echo «Record updated successfully»;
> else echo «Error updating record: » . $conn->error;
>

Example (MySQLi Procedural)

$servername = «localhost»;
$username = «username»;
$password = «password»;
$dbname = «myDB»;

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) die(«Connection failed: » . mysqli_connect_error());
>

$sql = «UPDATE MyGuests SET lastname=’Doe’ WHERE (mysqli_query($conn, $sql)) echo «Record updated successfully»;
> else echo «Error updating record: » . mysqli_error($conn);
>

Example (PDO)

$servername = «localhost»;
$username = «username»;
$password = «password»;
$dbname = «myDBPDO»;

try $conn = new PDO(«mysql:host=$servername;dbname=$dbname», $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$sql = «UPDATE MyGuests SET lastname=’Doe’ WHERE // Prepare statement
$stmt = $conn->prepare($sql);

// execute the query
$stmt->execute();

// echo a message to say the UPDATE succeeded
echo $stmt->rowCount() . » records UPDATED successfully»;
> catch(PDOException $e) echo $sql . «
» . $e->getMessage();
>

After the record is updated, the table will look like this:

id	firstname	lastname	email	reg_date
1	John	Doe	john@example.com	2014-10-22 14:26:15
2	Mary	Doe	mary@example.com	2014-10-23 10:22:30

Источник

MySQL — Update Query

There may be a requirement where the existing data in a MySQL table needs to be modified. You can do so by using the SQL UPDATE command. This will modify any field value of any MySQL table.

Syntax

The following code block has a generic SQL syntax of the UPDATE command to modify the data in the MySQL table −

UPDATE table_name SET field1 = new-value1, field2 = new-value2 [WHERE Clause]

• You can update one or more field altogether.
• You can specify any condition using the WHERE clause.
• You can update the values in a single table at a time.

The WHERE clause is very useful when you want to update the selected rows in a table.

Updating Data from the Command Prompt

This will use the SQL UPDATE command with the WHERE clause to update the selected data in the MySQL table tutorials_tbl.

Example

The following example will update the tutorial_title field for a record having the tutorial_id as 3.

root@host# mysql -u root -p password; Enter password:******* mysql> use TUTORIALS; Database changed mysql> UPDATE tutorials_tbl -> SET tutorial_title = 'Learning JAVA' -> WHERE tutorial_id = 3; Query OK, 1 row affected (0.04 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql>

Updating Data Using a PHP Script

PHP uses mysqli query() or mysql_query() function to update records in a MySQL table. This function takes two parameters and returns TRUE on success or FALSE on failure.

Syntax

Required — SQL query to update records in a MySQL table.

Optional — Either the constant MYSQLI_USE_RESULT or MYSQLI_STORE_RESULT depending on the desired behavior. By default, MYSQLI_STORE_RESULT is used.

Example

Try the following example to update a record in a table −

Copy and paste the following example as mysql_example.php −

    connect_errno ) < printf("Connect failed: %s
", $mysqli->connect_error); exit(); > printf('Connected successfully.
'); if ($mysqli->query('UPDATE tutorials_tbl set tutorial_title = "Learning Java" where tutorial_id = 4')) < printf("Table tutorials_tbl updated successfully.
"); > if ($mysqli->errno) < printf("Could not update table: %s
", $mysqli->error); > $sql = "SELECT tutorial_id, tutorial_title, tutorial_author, submission_date FROM tutorials_tbl"; $result = $mysqli->query($sql); if ($result->num_rows > 0) < while($row = $result->fetch_assoc()) < printf("Id: %s, Title: %s, Author: %s, Date: %d 
", $row["tutorial_id"], $row["tutorial_title"], $row["tutorial_author"], $row["submission_date"]); > > else < printf('No record found.
'); > mysqli_free_result($result); $mysqli->close(); ?>  

Output

Access the mysql_example.php deployed on apache web server and verify the output. Here we’ve entered multiple records in the table before running the select script.

Connected successfully. Table tutorials_tbl updated successfully. Id: 1, Title: MySQL Tutorial, Author: Mahesh, Date: 2021 Id: 2, Title: HTML Tutorial, Author: Mahesh, Date: 2021 Id: 3, Title: PHP Tutorial, Author: Mahesh, Date: 2021 Id: 4, Title: Learning Java, Author: Mahesh, Date: 2021 Id: 5, Title: Apache Tutorial, Author: Suresh, Date: 2021

Источник