The basic process of database manipulation is:
1. Connecting to the database server
2. Select Database
3. Execute SQL statement
4. Processing result set
5, printing operation information
The related functions used are
Resource mysql_connect ([string server [, String username [, string password [, bool new_link [, int client_flags]]] Connecting to a database server
Resource Mysql_pconnect ([string server [, String username [, string password [, int client_flags]]]) connecting to the database server, long connection
int Mysql_affected_rows ([resource link_identifier]) gets the number of record rows that were affected by the most recent link_identifier or DELETE query associated with insert,update.
bool Mysql_close ([resource link_identifier]) returns TRUE if successful, and returns FALSE if it fails.
int Mysql_errno ([resource link_identifier]) returns the error number of the previous MySQL function and returns 0 (0) If there is no error.
string Mysql_error ([resource link_identifier]) returns the error text of the previous MySQL function, and returns ' (an empty string) if there is no error. If you do not specify a connection resource number, the error message is fetched from the MySQL server using the last successfully opened connection.
array mysql_fetch_array (resource result [, int result_type]) returns an array generated from rows obtained from the result set, or FALSE if there are no more rows.
bool Mysql_free_result (resource result) releases all the memory associated with results of the resulting identifier.
int Mysql_num_fields (Resource results) returns the number of fields in the result set.
int Mysql_num_rows (Resource results) returns the number of rows in the result set. This command is valid only for SELECT statements. To obtain the number of rows affected by the Insert,update or DELETE query, use Mysql_affected_rows ().
resource mysql_query (string query [, resource Link_identifier]) sends a query to the currently active database in the server associated with the specified connection identifier. If Link_identifier is not specified, the previous open connection is used. If there is no open connection, this function attempts to call the mysql_connect () function without arguments to establish a connection and use it. Query results will be cached
The code is as follows:
Copy Code code as follows:
Class MySQL {
Private $db _host; Database Host
Private $db _user; Database login Name
Private $db _pwd; Database login Password
Private $db _name; Database name
Private $db _charset; Database character encoding
Private $db _pconn; Long connection Identification bit
Private $debug; Debug Open
Private $conn; Database connection Identification
Private $msg = ""; Database manipulation Information
Private $sql = ""; SQL statements to be executed
Public function __construct ($db _host, $db _user, $db _pwd, $db _name, $db _chaeset = ' UTF8 ', $db _pconn = False, $debug = False ) {
$this->db_host = $db _host;
$this->db_user = $db _user;
$this->db_pwd = $db _pwd;
$this->db_name = $db _name;
$this->db_charset = $db _chaeset;
$this->db_pconn = $db _pconn;
$this->result = ';
$this->debug = $debug;
$this->initconnect ();
}
Public Function Initconnect () {
if ($this->db_pconn) {
$this->conn = @mysql_pconnect ($this->db_host, $this->db_user, $this->db_pwd);
} else {
$this->conn = @mysql_connect ($this->db_host, $this->db_user, $this->db_pwd);
}
if ($this->conn) {
$this->query ("SET NAMES"). $this->db_charset);
} else {
$this->msg = "DB connection error, error number:". Mysql_errno (). "Error Reason:". Mysql_error ();
}
$this->selectdb ($this->db_name);
}
Public Function Selectdb ($dbname) {
if ($dbname = = "") {
$this->db_name = $dbname;
}
if (!mysql_select_db ($this->db_name, $this->conn)) {
$this->msg = "Database Unavailable";
}
}
Public Function query ($sql, $debug = False) {
if (! $debug) {
$this->result = @mysql_query ($sql, $this->conn);
} else {
}
if ($this->result = = False) {
$this->msg = "SQL execution error, wrong number:". Mysql_errno (). "Error Reason:". Mysql_error ();
}
Var_dump ($this->result);
}
Public Function Select ($tableName, $columnName = "*", $where = "") {
$sql = "Select". $columnName. "From". $tableName;
$sql. = $where? "WHERE". $where: null;
$this->query ($sql);
}
Public function FindAll ($tableName) {
$sql = "SELECT * from $tableName";
$this->query ($sql);
}
Public Function Insert ($tableName, $column = Array ()) {
$columnName = "";
$columnValue = "";
foreach ($column as $key => $value) {
$columnName. = $key. ",";
$columnValue. = "'". $value. "',";
}
$columnName = substr ($columnName, 0, strlen ($columnName)-1);
$columnValue = substr ($columnValue, 0, strlen ($columnValue)-1);
$sql = "INSERT into $tableName ($columnName) VALUES ($columnValue)";
$this->query ($sql);
if ($this->result) {
$this->msg = "Data insert succeeded. The newly inserted ID is: ". mysql_insert_id ($this->conn);
}
}
Public Function Update ($tableName, $column = Array (), $where = "") {
$updateValue = "";
foreach ($column as $key => $value) {
$updateValue. = $key. "='" . $value. "',";
}
$updateValue = substr ($updateValue, 0, strlen ($updateValue)-1);
$sql = "UPDATE $tableName SET $updateValue";
$sql. = $where? "WHERE $where": null;
$this->query ($sql);
if ($this->result) {
$this->msg = "Data update succeeded. Number of affected rows: ". Mysql_affected_rows ($this->conn);
}
}
Public Function Delete ($tableName, $where = "") {
$sql = "DELETE from $tableName";
$sql. = $where? "WHERE $where": null;
$this->query ($sql);
if ($this->result) {
$this->msg = "Data deletion succeeded. Number of affected rows: ". Mysql_affected_rows ($this->conn);
}
}
Public Function Fetcharray ($result _type = Mysql_both) {
$resultArray = Array ();
$i = 0;
while ($result = mysql_fetch_array ($this->result, $result _type)) {
$resultArray [$i] = $result;
$i + +;
}
return $resultArray;
}
Public Function Fetchobject () {
Return Mysql_fetch_object ($this->result);
// }
Public Function Printmessage () {
return $this->msg;
}
Public Function Freeresult () {
@mysql_free_result ($this->result);
}
Public Function __destruct () {
if (!empty ($this->result)) {
$this->freeresult ();
}
Mysql_close ($this->conn);
}
}
The calling code is as follows
Copy Code code as follows:
Require_once ' mysql_V1.class.php ';
Require_once ' commonfun.php ';
$db = new MySQL (' localhost ', ' root ', ' ', ' test ');
Select Check
$db->select ("User", "*", "username = ' System '");
$result = $db->fetcharray (MYSQL_ASSOC);
Print_r ($result);
Dump ($db->printmessage ());
Insert Increase
$userInfo = Array (' username ' => ' system ', ' Password ' => MD5 ("system"));
$db->insert ("user", $userInfo);
Dump ($db->printmessage ());
Update change
$userInfo = Array (' Password ' => MD5 ("123456"));
$db->update ("User", $userInfo, "id = 2");
Dump ($db->printmessage ());
Delete deletion
$db->delete ("user", "id = 1");
Dump ($db->printmessage ());
FindAll Query All
$db->findall ("user");
$result = $db->fetcharray ();
Dump ($result);
PS, the individual prefers the dump function of TP, so the friendly print function is copied in the commonfun.php file. When used, it can be changed to Print_r ().
