A, connecting and disconnecting the database
1, using the mysqli extension (recommended), only for mysql database
Object-oriented approach
the mysqli new new CON = $ (IP, User, password);
IF ($ con-> connect_error) {
the dir (. "connection failed" $ con-> connect_error);
} the else {
echo "connection successful";
}
$ con-> cloase ();
Direct method (process-oriented)
$con = mysqli_connect(ip,user,password);
if($con){
echo mysqli_connect_error();
} else {
echo "连接成功";
}
mysqli_close($con)
2, using mysql extension (PHP <= 5.0), starting in 2012 is not recommended
3, the use of PDO (php data objects) technology (preventing sql injection) object-oriented manner (recommended), 12 kinds can be applied to the database
try{
$con = new PDO("mysql:host=ip;",user,passwod);
echo "连接成功";
}
catch(PDOException $error){
echo $error->getMessage();
}
$con = null;
Second, the implementation of sql statement
SQL = $ "cteate db_name Database";
$ Result = "the mysqli_query (CON $, $ SQL)";
IF () {
echo "success";
} the else {
echo mysqli_error ($ CON); // print error
}
mysqli_close ($ con) // close the database
Record mysqli_num_rows ($ result) // number of queries
mysqli_field_count ($ result) // queries column
mysql_fetch_all ($ result) // query all data
mysqli_fetch_assoc ($ result) // a result of the execution into an array, the associated array
Print all arrays
while ($rows = mysqli_fetch_assoc($result)) {
print_r($row);
}