要怎样设置呢？A00001, A00002... A00010

nic1983

Hi,
我想问问，我要怎样设置呢？
我用 php n mysql
我要怎样auto generate 这样的agent id呢？
A00001, A00002 ... A00010
谢谢回答

雷克斯R

給你參考

function generate_agent_id(){
    $sql = "select agent_id from agent order by agent_id desc limit 1";
        $result = mysql_query($sql);
            if (mysql_num_rows($result) > 0){            
                $agent_id = mysql_result($result, 0,"agent_id" );
                $agent_id = substr($agent_id, 1);
                $agent_id = (int) $agent_id;
                $agent_id++;               
                $n = 5 - strlen($agent_id);
                $agent_id = "A" . str_repeat("0", $n) . $agent_id;                        
            } else {
                $agent_id = "A00001";
            }
    return $agent_id;                        
}

nic1983

回复 2# 雷克斯R

先谢谢你
想问下，如果下一个agent,那他的agent id是不是自动成为A00002呢？

kkwpms99

the best way of course is using "database sequence number" lah...high recommanded for web based system...!!

simple reason is because web based system will facing multiple users access concurrently...thus it may raised some data integrity issue.

like above function...this function is query the latest agent number from the member table then add one in order to create new agent number...plz imagine that if more than one member get the same latest agent number... then the next new agent number will be share by all those member lor...this is the main problem for above problem...

nic1983

回复 4# kkwpms99

说的也有道理
所以有任何意见呢？
要怎样做呢？

kkwpms99

Juz sory i reply by using english word first...

Firstly, i m not familiar with mySQL script..most of the time i m using ORACLE database.

so in Oracle DB, it can let u to create SEQUENCE object. after the object created then u can call use the object by using SQL script. this link for ur reference:  http://www.techonthenet.com/oracle/sequences.php

but the object only can generate numeric number in sequence. thus, u can call the object to create new number to u first...then temporarily store in an variable. after that, convert the number to string and format it to ur desire pattern.

this got one advantage is to ensure data integrity. if u interest on y this can ensure data is unique, u need to find the answer urself. it is difficult to let me explain to u here...but the concept actually very simple but difficult to write it out since i m not really good in writing...

above link can help u understand better...

nic1983

回复 6# kkwpms99

你回复英文没有问题
但只怕版主看到会扣分而已
但还是要谢谢你哦