在运维工作中经常部署各种运维环境,涉及mysql数据库的安装也是时常需要的。mysql数据库安装可以选择yum在线安装,但是这种安装的mysql一般是系统自带的,版本方面可能跟需求不太匹配。

##########################################################
Mysql数据库可以选用YUM方法在线安装
[root@host-test-huanqiu ~]# yum -y install mysql mysql-server
[root@host-test-huanqiu ~]# /etc/init.d/mysqld start
[root@host-test-huanqiu ~]# mysqladmin password "123456"
[root@host-test-huanqiu ~]# mysql -p123456
mysql> select version();
+-----------+
| version() |
+-----------+
| 5.1.73 |
+-----------+
1 row in set (0.00 sec
##########################################################

废话不多说,以下是Centos6系统下源码安装Mysql的操作记录,方便参考~

1、卸载旧版本
[root@host-test-huanqiu ~]# rpm -qa | grep mysql
mysql-5.1.73-7.el6.x86_64
mysql-libs-5.1.73-7.el6.x86_64
mysql-server-5.1.73-7.el6.x86_64

#普通删除模式
[root@host-test-huanqiu ~]# rpm -e mysql-5.1.73-7.el6.x86_64 mysql-libs-5.1.73-7.el6.x86_64 mysql-server-5.1.73-7.el6.x86_64
# 强力删除模式,如果使用上面命令删除时,提示有依赖的其它文件,则用该命令可以对其进行强力删除
[root@host-test-huanqiu ~]# rpm -e --nodeps mysql-5.1.73-7.el6.x86_64 mysql-libs-5.1.73-7.el6.x86_64 mysql-server-5.1.73-7.el6.x86_64

#删除/etc/my.cnf
[root@host-test-huanqiu ~]# rm /etc/my.cnf

2、安装编译代码需要的包
[root@host-test-huanqiu ~]# yum -y install make gcc-c++ cmake bison-devel ncurses-devel

3、创建mysql用户,不建立mysql用户家目录(加-M参数),也就是禁用mysql账号登陆系统
[root@host-test-huanqiu ~]# groupadd mysql
[root@host-test-huanqiu ~]# useradd -g mysql mysql -M -s /sbin/nologin

4、下载MySQL,源码编译安装

[root@host-test-huanqiu ~]# cd /usr/local/src
[root@host-test-huanqiu src]# wget -c http://ftp.ntu.edu.tw/MySQL/Downloads/MySQL-5.6/mysql-5.6.34.tar.gz [root@host-test-huanqiu src]# tar -zxvf mysql-5.6.34.tar.gz
[root@host-test-huanqiu src]# cd mysql-5.6.34/
[root@host-test-huanqiu mysql-5.6.34]# cmake -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DMYSQL_DATADIR=/data/mysql/data -DSYSCONFDIR=/etc -DWITH_MYISAM_STORAGE_ENGINE=1 -DWITH_INNOBASE_STORAGE_ENGINE=1 -DWITH_MEMORY_STORAGE_ENGINE=1 -DWITH_READLINE=1 -DMYSQL_UNIX_ADDR=/var/lib/mysql/mysql.sock -DMYSQL_TCP_PORT=3306 -DENABLED_LOCAL_INFILE=1 -DWITH_PARTITION_STORAGE_ENGINE=1 -DEXTRA_CHARSETS=all -DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci
[root@host-test-huanqiu mysql-5.6.34]# make && make install

5、配置MySQL

修改/usr/local/mysql权限
[root@host-test-huanqiu mysql-5.6.34]# mkdir -p /data/mysql/data
[root@host-test-huanqiu mysql-5.6.34]# chown -R mysql:mysql /usr/local/mysql
[root@host-test-huanqiu mysql-5.6.34]# chown -R mysql:mysql /data/mysql/data 执行初始化配置脚本,创建系统自带的数据库和表
[root@host-test-huanqiu mysql-5.6.34]# cd /usr/local/mysql
[root@host-test-huanqiu mysql]# ./scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data/mysql/data --user=mysql //如果后续不小心删除了这个数据目录或这个目录下的文件被误操作删除了,还可以利用这个命令重新初始化

需要特别注意:
在启动MySQL服务时,会按照一定次序搜索my.cnf,先在/etc目录下找,找不到则会搜索"$basedir/my.cnf",在本例中就是 /usr/local/mysql/my.cnf,这是新版MySQL的配置文件的默认位置!

另外:
在CentOS 6.4版操作系统最小安装完成后,默认会在/etc目录下存在一个my.cnf,需要将此文件更名为其他的名字,如:/etc/my.cnf.bak,否则,该文件会干扰源码安装的MySQL的正确配置,造成无法启动。
在使用"yum update"更新系统后,需要检查下/etc目录下是否会多出一个my.cnf,如果多出,将它重命名成别的。否则,MySQL将使用这个配置文件启动,可能造成无法正常启动等问题。
--------------------------------------------------------------------------------------------------------------------------------------------------------------

启动MySQL
添加服务,拷贝服务脚本到init.d目录,并设置开机启动
[root@host-test-huanqiu mysql]# cp support-files/mysql.server /etc/init.d/mysql
[root@host-test-huanqiu mysql]# chkconfig mysql on
[root@host-test-huanqiu mysql]# service mysql start   //启动前,要先配置my.cnf文件(如下), 并确保/data/mysql/data和/usr/local/mysql的mysql权限

如果启动报错:
[root@slave-server mysql]# service mysql start
Starting MySQL.Logging to '/data/mysql/data/mysql-error.log'.
170416 12:55:28 mysqld_safe Directory '/usr/local/mysql/var' for UNIX socket file don't exists.
ERROR! The server quit without updating PID file (/data/mysql/data/mysql.pid). 解决办法:
[root@slave-server mysql]# mkdir /usr/local/mysql/var
[root@slave-server mysql]# chown -R mysql:mysql /usr/local/mysql
[root@slave-server mysql]# service mysql start
Starting MySQL.. SUCCESS!

配置用户和环境变量

MySQL启动成功后,root默认没有密码,需要设置root密码,设置之前,需要先设置PATH,否则不能直接调用mysql
修改/etc/profile文件,在文件末尾添加
[root@host-test-huanqiu mysql]# vim /etc/profile
........
export PATH=$PATH:/usr/local/mysql/bin
[root@host-test-huanqiu mysql]# source /etc/profile 到此,就可以直接mysql登陆了
[root@host-test-huanqiu mysql]# mysql -uroot
.......
mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.33 |
+-----------+
1 row in set (0.00 sec)

登陆mysql,若是报错如下:

[root@test2-235 mysql]# mysql
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) 解决办法
[root@test2-235 mysql]# mkdir /var/lib/mysql/
[root@test2-235 mysql]# ln -s /usr/local/mysql/var/mysql.sock /var/lib/mysql/mysql.sock

修改root密码,执行命令如下

mysql> SET PASSWORD = PASSWORD('123456');

若要设置root用户可以远程访问,执行
mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'password' WITH GRANT OPTION;
使授权立即生效
mysql> FLUSH PRIVILEGES; 也可以使用mysqladmin命令设置mysql密码
[root@host-test-huanqiu mysql]# mysqladmin password 123456 #安装mysql后第一次设置密码
[root@host-test-huanqiu mysql]# mysqladmin -p 旧密码 password 新密码 #重置密码

最后配置防火墙

默认防火墙的3306端口默认没有开启,若要远程访问,需要开启这个端口.也可以做下白名单,比如只允许192.168.1.0/24网段的客户机访问本机的mysql。
[root@host-test-huanqiu mysql]# vim /etc/sysconfig/iptables
.......
-A INPUT -s 192.168.1.0/24 -p tcp -m tcp -m state --state NEW -dport 3306 -j ACCEPT

----------------------------------------------------------------------------------------------------------------------------------
下面贴下mysql6.x的my.cnf配置

[client]
port = 3306
socket = /usr/local/mysql/var/mysql.sock [mysqld]
port = 3306
socket = /usr/local/mysql/var/mysql.sock basedir = /usr/local/mysql/
datadir = /data/mysql/data
pid-file = /data/mysql/data/mysql.pid
user = mysql
bind-address = 0.0.0.0
server-id = 1
sync_binlog=1
log_bin = mysql-bin skip-name-resolve back_log = 600 max_connections = 3000
max_connect_errors = 3000 table_open_cache = 512
max_allowed_packet = 16M
binlog_cache_size = 16M
max_heap_table_size = 16M
tmp_table_size = 256M read_buffer_size = 1024M
read_rnd_buffer_size = 1024M
sort_buffer_size = 1024M
join_buffer_size = 1024M
key_buffer_size = 8192M thread_cache_size = 8 query_cache_size = 512M
query_cache_limit = 1024M ft_min_word_len = 4 binlog_format = mixed
expire_logs_days = 30 log_error = /data/mysql/data/mysql-error.log
slow_query_log = 1
long_query_time = 1
slow_query_log_file = /data/mysql/data/mysql-slow.log performance_schema = 0
explicit_defaults_for_timestamp skip-external-locking default_storage_engine = InnoDB
innodb_file_per_table = 1
innodb_open_files = 500
innodb_buffer_pool_size = 4096M #这个参数一般设置为服务器最大内存的60%
innodb_write_io_threads = 1000
innodb_read_io_threads = 1000
innodb_thread_concurrency = 8
innodb_purge_threads = 1
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 4M
innodb_log_file_size = 32M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120 bulk_insert_buffer_size = 8M
myisam_sort_buffer_size = 8M
myisam_max_sort_file_size = 2G
myisam_repair_threads = 1 interactive_timeout = 28800
wait_timeout = 28800 [mysqldump]
quick
max_allowed_packet = 16M [myisamchk]
key_buffer_size = 8M
sort_buffer_size = 8M
read_buffer = 4M
write_buffer = 4M sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
port = 3306

针对上面的部署过程,为了便于以后安装mysql环境,编写了下面的安装脚本,直接运行这个脚本就能自动化构建mysql环境了。
[root@slave-server ~]# cat mysql.sh                    (下载地址:https://pan.baidu.com/s/1gfEKC9d    密码:6ec3)

#!/bin/bash
#卸载系统自带的Mysql
/bin/rpm -e $(/bin/rpm -qa | grep mysql|xargs) --nodeps
/bin/rm -f /etc/my.cnf #安装编译代码需要的包
/usr/bin/yum -y install make gcc-c++ cmake bison-devel ncurses-devel #编译安装mysql5.6
/usr/sbin/groupadd mysql
/usr/sbin/useradd -g mysql mysql -M -s /sbin/nologin cd /usr/local/src
wget -c http://ftp.ntu.edu.tw/MySQL/Downloads/MySQL-5.6/mysql-5.6.37.tar.gz
/bin/tar -zxvf mysql-5.6.37.tar.gz
cd mysql-5.6.37/
/usr/bin/cmake -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DMYSQL_DATADIR=/data/mysql/data -DSYSCONFDIR=/etc -DWITH_MYISAM_STORAGE_ENGINE=1 -DWITH_INNOBASE_STORAGE_ENGINE=1 -DWITH_MEMORY_STORAGE_ENGINE=1 -DWITH_READLINE=1 -DMYSQL_UNIX_ADDR=/var/lib/mysql/mysql.sock -DMYSQL_TCP_PORT=3306 -DENABLED_LOCAL_INFILE=1 -DWITH_PARTITION_STORAGE_ENGINE=1 -DEXTRA_CHARSETS=all -DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci
make && make install #修改/usr/local/mysql权限
mkdir -p /data/mysql/data
/bin/chown -R mysql:mysql /usr/local/mysql
/bin/chown -R mysql:mysql /data/mysql/data #执行初始化配置脚本,创建系统自带的数据库和表
/usr/local/mysql/scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data/mysql/data --user=mysql #配置my.cnf
cat > /usr/local/mysql/my.cnf << EOF
[client]
port = 3306
socket = /usr/local/mysql/var/mysql.sock [mysqld]
port = 3306
socket = /usr/local/mysql/var/mysql.sock basedir = /usr/local/mysql/
datadir = /data/mysql/data
pid-file = /data/mysql/data/mysql.pid
user = mysql
bind-address = 0.0.0.0
server-id = 1
sync_binlog=1
log_bin = mysql-bin skip-name-resolve
#skip-networking
back_log = 600 max_connections = 3000
max_connect_errors = 3000
##open_files_limit = 65535
table_open_cache = 512
max_allowed_packet = 16M
binlog_cache_size = 16M
max_heap_table_size = 16M
tmp_table_size = 256M read_buffer_size = 1024M
read_rnd_buffer_size = 1024M
sort_buffer_size = 1024M
join_buffer_size = 1024M
key_buffer_size = 8192M thread_cache_size = 8 query_cache_size = 512M
query_cache_limit = 1024M ft_min_word_len = 4 binlog_format = mixed
expire_logs_days = 30 log_error = /data/mysql/data/mysql-error.log
slow_query_log = 1
long_query_time = 1
slow_query_log_file = /data/mysql/data/mysql-slow.log performance_schema = 0
explicit_defaults_for_timestamp ##lower_case_table_names = 1 skip-external-locking default_storage_engine = InnoDB
##default-storage-engine = MyISAM
innodb_file_per_table = 1
innodb_open_files = 500
innodb_buffer_pool_size = 4096M
innodb_write_io_threads = 1000
innodb_read_io_threads = 1000
innodb_thread_concurrency = 8
innodb_purge_threads = 1
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 4M
innodb_log_file_size = 32M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120 bulk_insert_buffer_size = 8M
myisam_sort_buffer_size = 8M
myisam_max_sort_file_size = 2G
myisam_repair_threads = 1 interactive_timeout = 28800
wait_timeout = 28800 [mysqldump]
quick
max_allowed_packet = 16M [myisamchk]
key_buffer_size = 8M
sort_buffer_size = 8M
read_buffer = 4M
write_buffer = 4M sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
port = 3306
EOF #启动mysql服务
cd /usr/local/mysql
/bin/mkdir var
/bin/chown -R mysql.mysql var
cp support-files/mysql.server /etc/init.d/mysql
/sbin/chkconfig mysql on
service mysql start #设置环境变量
echo "export PATH=$PATH:/usr/local/mysql/bin" >> /etc/profile
source /etc/profile #设置mysql登陆密码,初始密码为123456
/bin/mkdir -p /var/lib/mysql
ln -s /usr/local/mysql/var/mysql.sock /var/lib/mysql/mysql.sock
mysql -e "SET PASSWORD = PASSWORD('123456');"
mysql -p123456 -e "GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'password' WITH GRANT OPTION;"
mysql -p123456 -e "FLUSH PRIVILEGES;"

####################  编写mysql登录脚本  ######################

[root@slave-server ~]# vim /etc/passwd
......
mysql:x:1001:1001::/home/mysql:/bin/bash
[root@slave-server ~]# mkdir /home/mysql
[root@slave-server ~]# chown -R mysql.mysql /home/mysql [root@slave-server ~]# vim /usr/local/mysql/bin/myin
#!/bin/bash
p=$1
shift
mysql -h"127.0.0.1" -P"$p" --default-character-set=utf8mb4 --show-warnings -uqw_cmdb -p'qw_cmdb123' -A --prompt="(\u@\p-\r:\m:\s:)[\d]> " "$@" [root@slave-server ~]# chmod 755 /usr/local/mysql/bin/myin [root@slave-server ~]# su - mysql
Last login: Mon Jun 25 17:16:20 CST 2018 on pts/6
-bash-4.2$ myin 3306 #切换到mysql用户下,使用"myin 3306"命令登录mysql
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 256
Server version: 5.6.40-log Source distribution Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. (bobo@3306-02:51:38:)[(none)]>

###################  centos7下启动mysql时的一个报错 #################

在centos7下如上记录操作后,在启动mysql服务的时候遇到下面一个报错:
[root@kevin mysql]# service mysql start
Starting MySQL.181013 22:18:35 mysqld_safe error: log-error set to '/var/log/mariadb/mariadb.log', however file don't exists. Create writable for user 'mysql'.
The server quit without updating PID file (/data/mysql/data[FAILED]id). 该问题为mysql 的一个小bug 。
临时处理办法为 直接创建一个 log-error 指定的空文件,并给适当的属主、属组权限即可。该问题已经在 版本 5.5.55, 5.6.36, 5.7.18, 8.0.1 中修复。
后续可以通过升级版本,来修复该问题。 [root@kevin mysql]# mkdir -p /var/log/mariadb
[root@kevin mysql]# touch /var/log/mariadb/mariadb.log
[root@kevin mysql]# chown -R mysql.mysql /var/log/mariadb
[root@kevin mysql]# service mysql start
Starting MySQL... [ OK ]
[root@kevin mysql]# ln -s /var/log/mariadb/mariadb.log /data/mysql/data/mysql-error.log
[root@zabbix data]# /etc/init.d/mysql restart
Shutting down MySQL.. [ 确定 ]
Starting MySQL.. [ 确定 ]

##################### Centos7下安装Mysql5.5的操作方法  ###################

一、检查本地是否安装过其他版本的mysql
[root@localhost ~]# /bin/rpm -e $(/bin/rpm -qa | grep mysql|xargs) --nodeps 如果之前使用yum方法安装了mysql,则需要删除之前mysql的默认数据目录
[root@localhost ~]# rm -rf /var/lib/mysql 二、下载mysql 5.5的服务器和客户端的安装包 
[root@localhost ~]# wget https://dev.mysql.com/get/Downloads/MySQL-5.5/MySQL-server-5.5.59-1.el7.x86_64.rpm
[root@localhost ~]# wget https://dev.mysql.com/get/Downloads/MySQL-5.5/MySQL-client-5.5.59-1.el7.x86_64.rpm 三、安装服务器和客户端
[root@localhost ~]# rpm -ivh --nodeps MySQL-server-5.5.59-1.el7.x86_64.rpm
[root@localhost ~]# rpm -ivh --nodeps MySQL-client-5.5.59-1.el7.x86_64.rpm 查看安装的mysql是否已安装成功 :
[root@localhost ~]# rpm -qa|grep -i mysql
MySQL-server-5.5.59-1.el7.x86_64
MySQL-client-5.5.59-1.el7.x86_64 四、启动mysql并设置mysql服务开机自启动
启动mysql:
[root@localhost ~]# service mysql start 设置开机自启动:
[root@localhost ~]# chkconfig mysql on 验证自启动是否成功:
[root@localhost ~]# chkconfig --list|grep mysql
........
mysql 0:off 1:off 2:on 3:on 4:on 5:on 6:off 五、登录mysql并设置密码 (如上安装后,默认登录mysql是无密码的)
[root@localhost ~]# mysql -uroot
.......
mysql> select version();
+------------+
| version() |
+------------+
| 5.5.59-log |
+------------+
1 row in set (0.00 sec) 设置mysql密码
mysql> set password=password('kevin@123'); 设置远程连接(比如远程连接的mysql用户名是kevin,密码是kevin@123)
mysql> grant all on *.* to 'kevin'@''% identified by "kevin@123"; 删除默认状态下password或host为空的字段,否则远程连接可能会失败!
删除后,最好保留下面两个字段的初始认证信息
mysql> select user,host,password from mysql.user;
+----------+-----------+-------------------------------------------+
| user | host | password |
+----------+-----------+-------------------------------------------+
| root | localhost | *394941A09DHJSADF6555A8D6AB59733AF2893 |
| kevin | % | *394941A09DHJSADF6555A8D6AB59733AF2893 |
+----------+-----------+-------------------------------------------+
2 rows in set (0.00 sec) mysql> flush privileges; 退出后,再次登录mysql,就需要输入设置的密码kevin@123才能成功登录了! 六、mysql配置文件
这里需要注意下,mysql5.5按照上面的rpm方式安装后,默认是没有/etc/my.cnf配置文件的!!! 至于为什么没有my.cnf这个文件而MySQL却也能正常启动和使用,这个有两说法:
1)my.cnf只是MySQL启动时的一个参数文件,可以没有它,这时MySQL会用内置的默认参数启动;
2)MySQL在启动时自动使用/usr/share/mysql/my-medium.cnf文件,这种说法仅限于rpm包安装的MySQL。 解决办法:
只需复制/usr/share/mysql/my-medium.cnf文件到/etc目录,并改名为my.cnf即可: [root@localhost ~]# cp /usr/share/mysql/my-medium.cnf /etc/my.cnf 重启mysql服务
[root@localhost ~]# service mysql restart 七、关闭mysql区分大小写功能(即要求mysql对字段的大小写不敏感)
[root@localhost ~]# vim /etc/my.cnf
........
[mysqld]
........
lower_case_table_names = 1 重启mysql服务
[root@localhost ~]# service mysql restart 登录查看
mysql> show variables like "%case%";
+------------------------+-------+
| Variable_name | Value |
+------------------------+-------+
| lower_case_file_system | OFF |
| lower_case_table_names | 1 |
+------------------------+-------+
2 rows in set (0.00 sec) 当lower_case_table_names的值为1时,说明mysql已经关闭了区分大小写!

Centos6 系统下源码方式安装Mysql 记录的更多相关文章

  1. 2-14 MySQL初步认识,及CentOS6.8环境,源码方式安装MySQL

    什么是数据库: 存放数据的仓库RDBMS-->(Relational Database Management System) 关系型数据库管理系统DBMS--->(Database Man ...

  2. Mac系统下源码编译安装MySQL 5.7.17

    1.下载并解压到:/Users/xiechunping/Softwares/mysql-5.7.17下载地址:http://ftp.ntu.edu.tw/pub/MySQL/Downloads/MyS ...

  3. centos7下源码方式安装gitlab8.9+发送邮件+ldap

    CentOS7下源码方式安装gitlab 环境描述 操作系统: centos7 redis: >=2.8 mysql >=5.5.14 git >=2.7.4 架构设计 一台gitl ...

  4. CentOS 6.6 下源码编译安装MySQL 5.7.5

    版权声明:转自:http://www.linuxidc.com/Linux/2015-08/121667.htm 说明:CentOS 6.6 下源码编译安装MySQL 5.7.5 1. 安装相关工具# ...

  5. centos6.8下源码编译安装tmux

    1. 获取源码 git clone https://github.com/tmux/tmux.git ~/tmux 2. 准备工作 2.1 安装ncurses开发库 yum install ncurs ...

  6. Linux下源码编译安装MySql,centeros7

    1. 安cmake工具 # yum install -y cmake 2. 创建mysql用户  #useradd -s /sbin/nologin mysql  //设置为非登陆用户(安全) 3. ...

  7. ubuntu下源码方式安装php5.4

    一.安装前准备 下载php-5.4.13.tar.gz最新版本放到/user/src目录下 二.安装 因为在安装php过程中,会依赖安装很多库,为了不让你反复安装,建议按步骤操作 安装autoconf ...

  8. linux下源码编译安装mysql

    1.安装依赖的包: yum install -y gdb cmake ncurses-devel bison bison-devel 2.创建mysql安装目录和数据文件目录 mkdir -p /us ...

  9. centos下源码编译安装MySQL

    解压下载的软件压缩包  tar xzvf mysql-5.1.63.tar.gz 进入解压的目录  cd mysql-5.1.63/ 安装需要的依赖包  yum install gcc gcc-c++ ...

随机推荐

  1. jlink之j-scope使用

    网上看到了j-scope的用法,可以把单片机的数据显示成波形,这个和我使用的STMStudio有点类似,但是有区别: 1.STMStudio这个需要stlink结合swo的输出口,j-scope不需要 ...

  2. win10怎么查看当前用户账号

    https://jingyan.baidu.com/article/9225544679ab37851648f489.html

  3. java 8 学习三(Stream API)

    集合讲的是数据,流讲的是计算. 流的数据处理功能支持类似于数据库的操作,以及函数式编程语言中的常用操作,如filter. map. reduce. find. match. sort等. 流操作可以顺 ...

  4. 使用Google学术简单方法汇总

    1 Google学术打不开,简单方法汇总. 2   谷歌学术镜像 http://dir.scmor.com/google/ 3,https://xs.glgoo.net/ 4, https://sch ...

  5. Presto Infrastructure at Lyft

    转载一篇关于 lyft presto 平台建设的实践 Overview Early in 2017 we started exploring Presto for OLAP use cases and ...

  6. 洛谷p1967货车运输(kruskal重构树)

    题面 题解中有很多说最优解是kruskal重构树 所以 抽了个早自习看了看这方面的内容 我看的博客 感觉真的挺好使的 首先对于kruskal算法来说 是基于贪心的思想把边权排序用并查集维护是否是在同一 ...

  7. openjudge1.2

    目录 1.2.1 1.2.2 1.2.3 1.2.4 1.2.5 1.2.6 1.2.7 1.2.8 1.2.9 1.2.10 1.2.1 描述 分别定义int,short类型的变量各一个,并依次输出 ...

  8. GoCN每日新闻(2019-10-28)

    GoCN每日新闻(2019-10-28) 1. 理解和攻击Go DSA验证漏洞 https://paul.querna.org/articles/2019/10/24/dsa-verify-poc/2 ...

  9. html 选择本地图片,显示选择的图片

    主要用的是html5的文件系统部分: <html> <head> <meta name="viewport" content="width= ...

  10. JavaScript初探系列(十一)——ES6

    一.前言 ECMAScript 6.0(以下简称 ES6)是 JavaScript 语言的下一代标准,已经在 2015 年 6 月正式发布了.它的目标,是使得 JavaScript 语言可以用来编写复 ...