PHP(二)

1.PHP事务加X锁

    $sql = "SET TRANSACTION ISOLATION LEVEL REPEATABLE READ";
    $result = mysql_query($sql, $con);

2.PHP随机整数

rand(min, max)，获得包括min、max在内的其范围内的随机整数

3.双引号

双引号内$array[$index]的形式有效，比如$str[0] = "A"; print "$str[0]";

4.php sleep

sleep(秒)
usleep(微秒)

5.microtime()

返回msec sec，比如0.25139300 1138197510，都以秒为单位

6.连接处理相关

连接状态: 0-NORMAL(正常) 1-ABORTED(异常退出) 2-TIMEOUT(超时)
当客户端退出或者php中断超时后，php会被通过调用关闭触发函数强制退出
相关函数：
int ignore_user_abort ( [bool setting] )
This function sets whether a client disconnect should cause a script. to be aborted. It will return the previous setting and can be called without an argument to not change the current setting and only return the current setting.
int connection_aborted ( void )
Returns TRUE if client disconnected.
int connection_status ( void )
Returns the connection status bitfield.

7.时区设置

比如，date_default_timezone_set('UTC');

8.设置报错级别

比如，error_reporting(E_ALL);

9.设置php.ini中选项值

比如，ini_set('display_errors', 'on');

10.字符串分割

explode(separator,string,limit);
比如，explode(" ",$str)