How to query the database in php and sort it in order

PHP is a popular programming language that is widely used in the development of web applications. In web applications, more than one database is often used to store and manage data. There are many ways to query the database in PHP, one of which is to sort in order.

In this article, we will explore how to use PHP to perform database query sorting.

1. What is the database query in order?

Normal order is a sorting method from small to large. In the database, positive order can be achieved using the ORDER BY statement. In this statement, you can specify which column to sort by, and whether to sort in ascending or descending order. If you want to sort in ascending order, you can use ASC, if you want to sort in descending order, you can use DESC.

For example, when we use the SELECT statement, we can add an ORDER BY clause at the end:

SELECT * FROM table ORDER BY column ASC;

This will sort the columns specified by column names in ascending order.

2. How to use PHP to query the database in order?

To use PHP to perform database query sorting, you need to use some PHP functions and statements. The following are the detailed steps:

1. Connect to the database

First, we need to connect to the database and select the table we want to query. This can be done using the PHP functions mysqli_connect() and mysqli_select_db() as shown below:

$conn = mysqli_connect("localhost", "username", "password", "database_name");
mysqli_select_db($conn, "table_name");

2. Write a SQL query statement

Secondly, we need to write a SQL query statement to select The data we need to query. In the query, we need to specify which column we want to sort by, and whether it is in ascending or descending order. For example:

$sql = "SELECT * FROM table_name ORDER BY column_name ASC";

This query will select all the data in the table and sort it in ascending order by the column specified by the column name.

3. Execute SQL query

Now, we need to use the mysqli_query() function to send the query to the MySQL server and then get the results. As shown below:

$result = mysqli_query($conn, $sql);

If the query is successful, $result will become an object containing the query results.

4. Process the query results

Finally, we need to use a loop statement to process the query results and output the data. For example:

while($row = mysqli_fetch_array($result)){
echo $row['column_name'];
}

This will output each row of data sorted in ascending order.

3. Summary

In this article, we learned the basic knowledge of PHP database query in order. By using the mysqli function in PHP, we can easily query and sort the data of the MySQL database in the web application. Using positive sorting allows us to better understand and manage data. If you are a PHP developer, these skills will be very useful in your job.

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