Summary of commonly used database deletion statements in PHP

There are many commonly used database deletion statements in PHP. This article will briefly introduce several commonly used methods.

DELETE statement

The DELETE statement is one of the most commonly used database deletion statements in PHP. It can delete one or more rows of data in a table. When deleting data, you need to first select the table to be deleted, and then use the DELETE statement to delete the data. The sample code is as follows:

//连接数据库
$conn = mysqli_connect("localhost", "username", "password", "database");

//删除一行数据
$sql = "DELETE FROM table_name WHERE id = 1";
mysqli_query($conn, $sql);

//删除多行数据
$sql = "DELETE FROM table_name WHERE id IN (1, 2, 3)";
mysqli_query($conn, $sql);

Note that you must be careful when using the DELETE statement to delete data. Once the data is deleted, it cannot be restored.

TRUNCATE statement

The TRUNCATE statement is a more powerful delete statement than the DELETE statement. It can delete the data of the entire table at one time, or delete specified rows in the table. Unlike the DELETE statement, the TRUNCATE statement will not record logs after executing the operation, which means that it is faster than the DELETE statement. The sample code is as follows:

//连接数据库
$conn = mysqli_connect("localhost", "username", "password", "database");

//删除整张表数据
$sql = "TRUNCATE TABLE table_name";
mysqli_query($conn, $sql);

//删除表中指定行数据
$sql = "TRUNCATE TABLE table_name WHERE id > 10";
mysqli_query($conn, $sql);

DROP statement

The DROP statement is a more powerful delete statement than the TRUNCATE statement. It can delete the entire table and also contains the structure of the table, that is, delete the table structure. and data. The sample code is as follows:

//连接数据库
$conn = mysqli_connect("localhost", "username", "password", "database");

//删除整个表
$sql = "DROP TABLE table_name";
mysqli_query($conn, $sql);

The above are several commonly used database deletion statements in PHP. Developers can choose the corresponding deletion statements according to their actual development needs. At the same time, to ensure security, it is recommended to back up data before performing operations such as DELETE, TRUNCATE, and DROP.

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