How to specify conditions to query the database in php

How to query the database by specifying conditions in php: 1. Create a user table in the database; 2. Use mysqli_select_db to select the database to be operated; 3. Specify query conditions through where; 4. Use the mysqli_fetch_assoc function to convert the results Just convert the set data into an array.

The operating environment of this article: Windows 7 system, PHP version 7.1, Dell G3 computer.

How to specify conditions to query the database in php?

In the mysql database, create a user table and insert multiple pieces of data into the table for testing.

Create a test.php file, and within the file, use the header() method to set the encoding format of the page to utf-8.

In the test.php file, connect to the mysql database and use mysqli_select_db to select the database to operate.

In the test.php file, create a sql statement to obtain the data of the user data table, and specify the query conditions through where, for example, the data with id 3 , and then use the mysqli_query function to execute the sql statement.

In the test.php file, use the mysqli_fetch_assoc function to convert the result set data into an array form, and use print_r to output the data.

Open the test.php file in the browser to view the results.

Recommended study: "PHP Video Tutorial"

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