Definition and usage
mysqli_query() function executes a query against the database.
Syntax
mysqli_query(connection,query,resultmode);
Parameter description:
connection Required, specifies the MySQL connection to be used.
query Required, specifies the query string.
resultmode Optional. a constant. Can be any of the following values:
1.MYSQLI_USE_RESULT (use this if you need to retrieve a large amount of data)
2.MYSQLI_STORE_RESULT (default)
Return value:
For a successful SELECT, SHOW, DESCRIBE or EXPLAIN query, a mysqli_result object will be returned. For other successful queries, TRUE will be returned. On failure, returns FALSE.
Update log: The asynchronous query function is added in PHP 5.3.0.
PHP mysqli_query() function usage example:
Execute a query against the database:
Delete database
<?php // 假定数据库用户名:root,密码:123456,数据库:RUNOOB $con=mysqli_connect("localhost","root","123456","RUNOOB"); if (mysqli_connect_errno($con)) { echo "连接 MySQL 失败: " . mysqli_connect_error(); } // 执行查询mysqli_query($con,"SELECT * FROM websites");mysqli_query($con,"INSERT INTO websites (name, url, alexa, country) VALUES ('百度','https://www.baidu.com/','4','CN')"); mysqli_close($con);?>
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