How to change max_allowed_packet value in mysql?
If you set it in the cnf(it may be my.ini file) you will likely need to restart the server. Optionally, that is a dynamic variable and can be SET GLOBAL or SET SESSION from the command line as well.So just do as follows.
mysql>show variables like’max_allowed_packet’;
mysql>set global max_allowed_packet=67108864;
mysql>exit;
Note: If you don't use global or use session,after execute exit command,max_allowed_packet value will be still 1048576.
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To_Days(end_time)-To_Days(start_time)
#两日期/时间之间相差的秒数：
SELECT UNIX_TIMESTAMP(end_time)- UNIX_TIMESTAMP(start_time);
#两日期/时间之间相差的时分数：
SELECT SEC_TO_TIME(UNIX_TIMESTAMP(end_time)- UNIX_T ......
mysql 大对象存取:
类型一般应该用mediumblod,
blob只能存2的16次方个byte,
mediumblod是24次方,
一般来说够用了.longblob是32次方有些大.
MYSQL默认配置只能存1M大小的文件,要修改配置,WIN版本的在mysql.ini文件中
修改max_allowed_packet,net_buffer_length等几个参数,或直接SET GLOBAL varName=value.
linux版� ......
Love in coding...
Free and Susan
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mysql.h在你mysql的安装目录下的include里面如:mysql\include
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如果编译连接时还是出错。就把libmysql.lib复制到你源程序的目 ......
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that tells
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