PHP之mysql数据库

1.连接数据库

mysql -u root -p

2.显示有几个数据库

show databses

3.创建数据库

<?php $con = mysql_connect ( "localhost", "root", "a76d290e04" );	if (! $con) {		die ( 'Could not connect: ' . mysql_error () );	}		if (! $con) {		die ( 'Could not connect: ' . mysql_error () );	}		if (mysql_query ( "CREATE DATABASE my_db", $con )) {		echo "Database created";	} else {		echo "Error creating database: " . mysql_error ();	}		mysql_select_db ( "my_db", $con );	$sql = "CREATE TABLE Persons 	(	FirstName varchar(15),	LastName varchar(15),	Age int	)";		mysql_query ( $sql, $con );		mysql_close ( $con );	  ?>

二.插入数据

<?php $con = mysql_connect ( "localhost", "root", "a76d290e04" );	if (! $con) {		die ( 'Could not connect: ' . mysql_error () );	}		if (! $con) {		die ( 'Could not connect: ' . mysql_error () );	}		mysql_select_db ( "my_db", $con );		$sql = "INSERT INTO Persons (FirstName, LastName, Age) VALUES ('$_POST[firstname]','$_POST[lastname]','$_POST[age]')";		if (! mysql_query ( $sql, $con )) {		die ( 'Error: ' . mysql_error () );	}	echo "1 record added";		mysql_close ( $con );?>

Firstname: Lastname: Age:

三.查询数据

<?php $con = mysql_connect ( "localhost", "root", "a76d290e04" );	if (! $con) {		die ( 'Could not connect: ' . mysql_error () );	}		if (! $con) {		die ( 'Could not connect: ' . mysql_error () );	}		mysql_select_db ( "my_db", $con );		$result = mysql_query("SELECT * FROM Persons");	while ( $row = mysql_fetch_array ( $result ) ) {		echo $row ['FirstName'] . " " . $row ['LastName'];		echo "<br />";}			mysql_close ( $con );?>