1, use mysqli operation MySQL
Example 1. Object oriented style
| The code is as follows |
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| <?php
$mysqli = new Mysqli ("localhost", "My_user", "My_password", "World"); /* Check Connection * *
if (Mysqli_connect_errno ()) {
printf ("Connect failed:%sn", Mysqli_connect_error ());
Exit ();
} printf ("Host Information:%sn", $mysqli->host_info); /* Close Connection * *
$mysqli->close ();
?> /**
* Above is to establish a connection with MySQL.
* Host: For MySQL host address type is character type.
* Username: for MySQL login username type is character.
* passwd: The MySQL login password type is character type.
* DB: is a character type for the MySQL database name.
* Port: The port number for the MySQL database.
*/
$sSQL = "SELECT * from DB";
/* The SQL statement that needs to be executed * *
$query = Mysqli_query ($connect, $sSQL);
/*
$connect: Link is a source of links
$sSQL: Query also refers to the SQL statement that needs to be executed
*/
while ($arr = Mysqli_fetch_array ($query)) {
/* $query: The results of cyclic $query * *
Print_r ($arr);
/* Enter the corresponding value of the field * *
}
Mysqli_free_result ($query);
/* Release result set * *
Mysqli_close ($connect);
/* Close Database connection/* |
2, use MySQL operation MySQL
In PHP, this task is done through the mysql_connect () function.
Grammar
Mysql_connect (Servername,username,password);
Example
In the following example, we store a connection in a variable ($con) in a script for later use. If the connection fails, the "Die" section is executed:
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<?php
$con = mysql_connect ("localhost", "Peter", "abc123");
if (! $con)
{
Die (' Could not connect: '. Mysql_error ());
} Some code ?> /**
* Above is to establish a connection with MySQL.
* Host: For MySQL host address type is character type.
* Username: for MySQL login username type is character.
* passwd: The MySQL login password type is character type.
* Port: The port number for the MySQL database.
*/
mysql_select_db ("db");
/*
Select Database
DB is the database name
*/
$sSQL = "SELECT * from DB";
/*sql Query Statement * *
$query = mysql_query ($sSQL);
/*
$sSQL: Query also refers to the SQL statement that needs to be executed
*/
while ($arr = Mysql_fetch_array ($query)) {
/* $query: The results of cyclic $query * *
/* Enter the corresponding value of the field * *
Print_r ($arr);
}
Mysql_free_result ($query);
/* Release result set * * |
Close connection
As soon as the script finishes, the connection closes. Use the Mysql_close () function if you want to close the connection in advance.
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<?php
$con = mysql_connect ("localhost", "Peter", "abc123");
if (! $con)
{
Die (' Could not connect: '. Mysql_error ());
} Some code Mysql_close ($con);
?> |
3. Using mysqli in OOP mode
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| $conn = new Mysqli (" host "," username "," passwd "," DB ", port);
/* *
* above is to establish a connection with MySQL.
* Host: is a character type for the MySQL host address type.
* Username: Character type for MySQL login username.
* passwd: Character type for the MySQL login password.
* DB: is a character type for the MySQL database name.
* Port: The port number for the MySQL database.
*/
$sSQL = "SELECT * from user";
/*sql Query statement */
$query = $conn->query ($sSQL); /*
$sSQL: Query also refers to the SQL statement to be executed
*/
while ($arr = $query->fetch_array ()) {
/* $query: Loop $ Results executed by query */
print_r ($arr);
}
$query->close ();
/* Release result set */
$conn->close ();
* Close Database connection */ |
