From 3cc22983a677358f02c61e09b3a5fb873dae99ae Mon Sep 17 00:00:00 2001 From: moralok Date: Thu, 11 Jan 2024 14:51:11 +0000 Subject: [PATCH] =?UTF-8?q?Add=20"MySQL=20=E5=B8=B8=E7=94=A8=E5=91=BD?= =?UTF-8?q?=E4=BB=A4"?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...20-09-14-MySQL-frequently-used-commands.md | 86 +++++++++++++++++++ 1 file changed, 86 insertions(+) create mode 100644 source/_posts/2020-09-14-MySQL-frequently-used-commands.md diff --git a/source/_posts/2020-09-14-MySQL-frequently-used-commands.md b/source/_posts/2020-09-14-MySQL-frequently-used-commands.md new file mode 100644 index 00000000..f7b022a0 --- /dev/null +++ b/source/_posts/2020-09-14-MySQL-frequently-used-commands.md @@ -0,0 +1,86 @@ +--- +title: MySQL 常用命令 +date: 2020-09-04 15:39:05 +tags: [mysql] +--- + +根据个人使用经验记录常用的 `MySQL` 命令作为备忘清单。 + + + +## MySQL + +|命令|描述| +|--|--| +|` mysql –h localhost –u root -P 3306 –p `|连接数据库| + +## 数据库 + +|命令|描述| +|--|--| +|`` SHOW DATABASES; ``|列出数据库| +|`` CREATE DATABASE IF NOT EXISTS `db_name` DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci; ``|创建数据库| +|`` DROP DATABASE `db_name`; ``|删除数据库| +|`` SHOW CREATE DATABASE `db_name`; ``|查看数据库的创建信息| +|`` USE `db_name`; ``|选择数据库| + + +## 表 + +|命令|描述| +|--|--| +|`` SHOW TABLES; ``|列出表| +|`` CREATE TABLE `table_name` ( ``
`` `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键 id', ``
`` `uid` varchar(20) NOT NULL DEFAULT '' COMMENT 'uid', ``
`` `status` tinyint(1) NOT NULL DEFAULT '1' COMMENT '状态: 0 无效 1 有效', ``
`` `gmt_create` bigint(13) unsigned NOT NULL COMMENT '创建时间', ``
`` PRIMARY KEY (`id`), ``
`` UNIQUE KEY `unq_idx_uid` (`uid`) ``
`` ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4 ROW_FORMAT=DYNAMIC COMMENT='表的描述'; ``|创建表| +|`` DROP TABLE `table_name`; ``|删除表| +|`` SHOW CREATE TABLE `table_name`; ``|查看表的创建信息| +|`` DESC `table_name`; ``|查看表的字段| +|`` ALTER TABLE `table_name` RENAME `new_table_name`; ``|查看表的字段| +|`` ALTER TABLE `table_name` MODIFY `field_name` field_type; ``|修改字段类型| +|`` ALTER TABLE `table_name` ADD `field_name` field_type AFTER `another_field_name`; ``|添加字段| +|`` ALTER TABLE `table_name` DROP `field_name`; ``|删除字段| +|`` ALTER TABLE `table_name` CHANGE `field_name` `new_field_name` new_field_type; ``|修改字段名称| + +## 增删改查 + +|命令|描述| +|--|--| +|`` INSERT INTO `table_name` (field_name1, field_name2) VALUES (value1, value2); ``|新增| +|`` SELECT * FROM `table_name` WHERE `field_name` = value; ``|查询| +|`` UPDATE `table_name` SET `field_name1` = value1 WHERE `field_name2` = value2; ``|更新| +|`` DELETE FROM `table_name` WHERE `field_name` = value; ``|删除| +|`` TRUNCATE `table_name`; ``|清空| + +## 事务 + +|命令|描述| +|--|--| +|` BEGIN; `
` START TRANSACTION; `|开启事务| +|` START TRANSACTION WITH CONSISTENT SNAPSHOT; `|开启事务并立即创建 read-view| +|` ROLLBACK; `|回滚事务| +|` COMMIT; `|提交事务| +|` SELECT @@autocommit; `|查看 autocommit，默认 1| +|` SET @@autocommit = 0; `|设置为手动提交| +|` SHOW VARIABLES LIKE 'transaction_isolation';`
` SHOW VARIABLES LIKE 'tx_isolation'; `|查看隔离级别| +|` SET transaction_isolation = 'READ-UNCOMMITTED'\|'READ-COMMITTED'\|'REPEATABLE-READ'\|'SERIALIZABLE'; `
` SET SESSION transaction isolation level READ UNCOMMITTED\|READ COMMITTED\|REPEATABLE-READ\|SERIALIZABLE; `|设置隔离级别| + +## 用户 + +|命令|描述| +|--|--| +|` CREATE USER 'username'@'ip' IDENTIFIED BY 'password'; `|创建用户| +|` GRANT ALL ON db_name.* TO 'username'@'ip'; `|授权| +|` FLUSH PRIVILEGES; `|刷新权限| +|` REVOKE ALL ON db_name.* FROM 'username'@'ip'; `|取消授权| +|` DROP USER 'username'@'ip'; `|删除用户| + +## 变量 + +全局变量、会话变量、用户变量、局部变量。 + +|命令|描述| +|--|--| +|` SHOW [GLOBAL\|SESSION] VARIABLES; `|查看全部变量| +|` SHOW [GLOBAL\|SESSION] VARIABLES [LIKE 匹配的模式]; `
` SELECT @@[GLOBAL\|SESSION].variable_name `|查看单个变量| +|` SET [GLOBAL\|SESSION] variable_name = value; `
` SET @@[GLOBAL\|SESSION].variable_name = value `|设置单个变量| + +> `SESSION` 可以省略。