<? PHP
/*************************************** ***********************
* Descript: MySQL database operation management class
*
* Author: young adults
* Email: wenadmin@sina.com
* QQ: 303015292
* MSN: wenguangqing@hotmail.com
**************************************** *********************/
/*
* Example 1: Obtain the sequence
* <?
* $ Db = new dB ();
* $ Result = $ db-> getseq ('art _ id', 2, 1 );
*?>
*/
/*
* Example 2: Paging Query
* <?
* $ Db = new dB ();
* $ Result = $ db-> & querypage ('select ID, name from table', 2, 10, db_fetch_assoc );
* Foreach ($ result as $ row)
* Echo $ row ['id'], '------'. $ row ['name']. '<br> ';
*?>
*/
/*
* Example 3: insert data
* <?
* $ Db = new dB ();
* $ Result = $ db-> execute ("insert into table (ID, name) values (1, 'name ')");
* If ($ result> 0) echo 'data inserted successfully ';
* Else echo 'data insertion failed ';
*?>
*/
/*
* Define database connection options
* @ Var db_host string Database Host name or address
* @ Var db_name string Database Name
* @ Var db_user string Database User Name
* @ Var db_pwd string password of the Database User
* @ Var db_pconnect Boolean whether to establish a persistent connection
*/
Define ('db _ host', 'localhost ');
Define ('db _ name', 'test ');
Define ('db _ user', 'root ');
Define ('db _ pwd ','');
Define ('db _ pconnect ', true );
/*
* Define the type of returned data query results
* @ Var db_fetch_assoc int result call method: $ result ['name']
* @ Var db_fetch_num int result call method: $ result [0]
* @ Var db_fetch_both INT: $ result ['name'] or $ result [0]
* @ Var db_fetch_object int result call method: $ result-> name
*/
Define ('db _ fetch_assoc ', 0 );
Define ('db _ fetch_num ', 1 );
Define ('db _ fetch_both ', 2 );
Define ('db _ fetch_object ', 3 );
/*
* Defines the name of the default sequence generator.
*/
Define ('db _ sequence_tablename', 'sequences '); Class dB {
/*
* Current database connection options
*/
VaR $ dbhost = db_host;
VaR $ dbname = db_name;
VaR $ dbtype = 'mysql ';
VaR $ dbuser = db_user;
VaR $ dbpwd = db_pwd;
VaR $ PCNN = db_pconnect;
/*
* Current Database Connection
*/
VaR $ CNN = '';
/*
* Data Query Result return type
*/
VaR $ queryfetchtype = db_fetch_assoc;
/*
* Initialization Function
*/
Function dB (){
$ This-> CNN = ($ this-> PCNN? Mysql_connect ($ this-> dbhost, $ this-> dbuser, $ this-> dbpwd ):
Mysql_connect ($ this-> dbhost, $ this-> dbuser, $ this-> dbpwd) or
$ This-> _ halt ('database connection error ');
Mysql_select_db ($ this-> dbname, $ this-> CNN) or $ this-> _ halt ('database selection error ');
}
/*
* Data Query Functions
*
* @ Param $ SQL string data query statement
* @ Param $ fetchtype int return type of the Data Query Result
*
* @ Return array data query result
*/
Function & query ($ SQL, $ fetchtype = db_fetch_assoc ){
$ DATA = array ();
$ Rs = & mysql_query ($ SQL, $ this-> CNN) or $ this-> _ halt ('data query error', $ SQL );
$ EXE = $ this-> _ getcommand ($ fetchtype );
While ($ ROW = & $ EXE ($ RS ))
$ Data [] = & $ row;
Return $ data;
}
/*
* Paging data query function
*
* @ Param $ SQL string data query statement
* @ Param $ page int current pre-query page number
* @ Param $ pagesize: the number of records displayed on each page.
* @ Param $ fetchtype int return type of the Data Query Result
*
* Data Query results and data paging information
* @ Return array ('pagesize' => Number of entries displayed on each page
* 'Recordcount' => total number of records
* 'Pagecount' => total number of pages
* 'Page' => current page number
* 'Isfirst' => whether the first page is displayed
* 'Isla' => whether to display the last page
* 'Start' => the sequence number of the first record in the returned result
* 'SQL' => the queried SQL statement
* 'Data' => query results
*)
* Data Query results and data paging information
*/
Function & querypage ($ SQL, $ page = 1, $ pagesize = 20, $ fetchtype = db_fetch_assoc ){
$ Countsql = preg_replace ('| select. * From | I', 'select count (*) Count from', $ SQL );
$ Data ['pagesize'] = (INT) $ pagesize <1? 20: (INT) $ pagesize;
$ Data ['recordcount'] = $ this-> getone ($ countsql, 'Count ');
$ Data ['pagecount'] = Ceil ($ data ['recordcount']/$ data ['pagesize']);
$ Data ['page'] = $ data ['pagecount'] = 0? 0: (INT) $ page <1? 1: (INT) $ page );
$ Data ['page'] = $ data ['page']> $ data ['pagecount']? $ Data ['pagecount']: $ data ['page'];
$ Data ['isfirst'] = $ data ['page']> 1? False: true;
$ Data ['isla'] = $ data ['page'] <$ data ['pagecount']? False: true;
$ Data ['start'] = ($ data ['page'] = 0 )? 1: ($ data ['page']-1) * $ data ['pagesize'] + 1;
$ Data ['SQL'] = $ SQL. 'limit'. ($ data ['start']-1). ','. $ data ['pagesize'];
$ Data ['data'] = & $ this-> query ($ data ['SQL'], $ fetchtype );
Return $ data;
}
/*
* Only 1st rows of data are returned for data query.
*
* @ Param $ SQL string data query statement
* @ Param $ fetchtype int return type of the Data Query Result
*
* @ Return array data query result
*/
Function & queryrow ($ SQL, $ fetchtype = db_fetch_assoc ){
$ Rs = & mysql_query ($ SQL, $ this-> CNN) or $ this-> _ halt ('single row data query error', $ SQL );
$ EXE = $ this-> _ getcommand ($ fetchtype );
Return $ EXE ($ RS );
}
/*
* Only data in column N of row 1st is returned for data query.
*
* @ Param $ SQL string data query statement
* @ Param $ field int returns the name or number of the data column.
*
* @ Return string returns the value of a single field.
*/
Function & getone ($ SQL, $ field = 0 ){
$ Rs = & mysql_query ($ SQL, $ this-> CNN) or $ this-> _ halt ('single Data Query error', $ SQL );
$ ROW = mysql_fetch_array ($ RS );
Return $ row [$ field];
}
/*
* Execute an SQL statement, including the execution statement of delect/insert/update...
*
* @ Param $ SQL string data query statement
*
* @ Return string returns the number of data rows affected by the statement.
*/
Function execute ($ SQL ){
$ Rs = mysql_query ($ SQL) or $ this-> _ halt ('Statement execution error', $ SQL );
Return mysql_affected_rows ($ this-> CNN );
}
/*
* Obtain the number of the last inserted data.
*/
Function getinsertid (){
Return mysql_insert_id ($ this-> CNN );
}
/*
* Sequence generator used to generate non-repeated sequence values
*
* @ Param $ fieldname string sequence name
* @ Param $ step int serial number Interval
* @ Param $ start int start value of the serial number
*
* @ Return int new Sequence Value
*/
Function getseq ($ fieldname, $ step = 1, $ start = 1 ){
$ Table = db_sequence_tablename;
$ Step = (INT) $ step;
$ Start = (INT) $ start;
$ Rs = mysql_query ("Update $ table set seq_num = seq_num + ($ step) Where seq_name = '$ fieldname '");
If (! $ Rs | mysql_affected_rows ($ this-> CNN) <1 ){
$ Rs = mysql_query ('select * from '. db_sequence_tablename, $ this-> CNN );
If (! $ RS ){
$ SQL = "CREATE TABLE $ table (
Seq_name varchar (20) not null,
Seq_num bigint (20) default 1 not null,
Primary Key (seq_name ))";
$ Rs = mysql_query ($ SQL) or $ this-> _ halt ('sequence generator table creation failed', $ SQL );
}
$ Rs = mysql_query ("insert into $ table values ('$ fieldname', $ start)") or
$ This-> _ halt ('add new sequence error', $ SQL );
$ Seq = $ start;
} Else {
$ Seq = & $ this-> getone ("select seq_num from $ table where seq_name = '$ fieldname '");
}
Return $ seq;
} Function _ getcommand ($ fetchtype ){
Switch ($ fetchtype ){
Case db_fetch_assoc: $ EXE = 'mysql _ fetch_assoc '; break;
Case db_fetch_num: $ EXE = 'mysql _ fetch_row '; break;
Case db_fetch_both: $ EXE = 'mysql _ fetch_array '; break;
Case db_fetch_object: $ EXE = 'mysql _ fetch_object '; break;
Default: $ EXE = 'mysql _ fetch_array '; break;
}
Return $ EXE;
} Function _ halt ($ MSG ){
$ Errno = mysql_errno ($ this-> CNN );
$ Errstr = mysql_error ($ this-> CNN );
Die ("Database Error: $ MSG <br> $ errno: $ errstr ");
}
}
?> |
