Mysql如何创建数据库

小编给大家分享一下Mysql如何创建数据库，相信大部分人都还不怎么了解，因此分享这篇文章给大家参考一下，希望大家阅读完这篇文章后大有收获，下面让我们一起去了解一下吧！4.1 create and drop databaseC:Usersadmin>mysql -h localhost -u root -pmysqlmysql: [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 3Server version: 5.7.14 MySQL Community
Server (GPL)Copyright (c) 2000, 2016, Oracle and/or its
affiliates. All rights reserved.Oracle is a registered trademark of Oracle
Corporation and/or itsaffiliates. Other names may be trademarks
of their respectiveowners.Type ‘help;’ or ‘h’ for help. Type ‘c’ to
clear the current input statement.mysql>
show databases;+——————–+| Database |+——————–+| information_schema || mysql || performance_schema || sys || test |+——————–+5 rows in set (0.00 sec)mysql>
create database example; #create
databaseQuery OK, 1 row affected (0.04 sec)mysql>
show databases;
#显示databases+——————–+| Database |+——————–+| information_schema || example || mysql || performance_schema || sys || test |+—————-免费主机域名—-+6 rows in set (0.00 sec)mysql> drop database example; #drop database;Query OK, 0 rows affected (0.04 sec)mysql> show databases;+——————–+| Database |+——————–+| information_schema || mysql || performance_schema || sys || test |+——————–+5 rows in set (0.00 sec)mysql> create database mysql;ERROR 1007 (HY000): Can’t create database
‘mysql’; database existsmysql> create database mydata;Query OK, 1 row affected (0.01 sec)4.2
存储引擎mysql>
show engines G*************************** 1. row
*************************** Engine: InnoDB Support:
DEFAULT Comment: Supports transactions, row-level locking, and foreign keysTransactions: YES XA: YES Savepoints: YES*************************** 2. row
*************************** Engine: MRG_MYISAM Support: YES Comment: Collection of identical MyISAM tablesTransactions: NO XA: NO Savepoints: NO*************************** 3. row *************************** Engine: MEMORY Support: YES Comment: Hash based, stored in memory, useful for temporary tablesTransactions: NO XA: NO Savepoints: NO*************************** 4. row
*************************** Engine: BLACKHOLE Support: YES Comment: /dev/null storage engine (anything you write to it disappears)Transactions: NO XA: NO Savepoints: NO*************************** 5. row
*************************** Engine: MyISAM Support:
YES Comment: MyISAM storage engineTransactions: NO XA: NO Savepoints: NO*************************** 6. row
*************************** Engine: CSV Support: YES Comment: CSV storage engineTransactions: NO XA: NO Savepoints: NO*************************** 7. row
*************************** Engine: ARCHIVE Support: YES Comment: Archive storage engineTransactions: NO XA: NO Savepoints: NO*************************** 8. row
*************************** Engine: PERFORMANCE_SCHEMA Support: YES Comment: Performance SchemaTransactions: NO XA: NO Savepoints: NO*************************** 9. row
*************************** Engine: FEDERATED Support: NO Comment: Federated MySQL storage engineTransactions: NULL XA: NULL Savepoints: NULL9 rows in set (0.00 sec)mysql>4.2.1 InnoDB engineInnoDB是mysql数据库中的免费主机域名存储引擎,innodb给mysql的表提供了事务，回滚，崩溃修复能力，多版本并发控制的事务安全(1) Innodb那个。存储引擎支持自动增长列auto_increment.(2) Innodb存储引擎支持外键(foreign
key)(3) Innodb存储引擎，创建的表的表结构在.frm文件中，数据和索引存储在innodb_data_home_dir和innodb_data_file_path定义的表空间(4) Innodb存储引擎的缺点是读写效率稍差，占用的数据空间相对较大。4.2.2 MyISAM engineMyISAM是mysql中常见的存储引擎MyISAM存储引擎的表存储成三个文件。文件的名字与表名相同，扩展名包括frm,MYD,MYI,.其中frm为扩展名的文件存储表的结构；MYD(MYData)为扩展名的文件存储数据，MYI(MYindex)为扩展名的文件存储引擎MyISAM存储引擎的优势在于占用空间小，处理速度快。缺点是不支持事务的完整性和并发性。4.2.3 MEMORY特殊存储引擎,表结构在disk上，数据在内存中。Memory表的大小受到显示，表的大小取决于两个参数max_rows和max_heap_table_size4.2.4 engines的选择.特性InnoDBMyISAMMEMORY事务安全支持无无存储限制64TB有有空间使用高低低内存使用高低高插入数据的速度低高高对外键的迟滞支持无无以上是“Mysql如何创建数据库”这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注云技术行业资讯频道！

相关推荐: MySQL中使用if not exists需要注意什么

小编给大家分享一下MySQL中使用if not exists需要注意什么，希望大家阅读完这篇文章之后都有所收获，下面让我们一起去探讨吧！环境MySQL 5.6.14事务隔离级别 读提交事务的开启和结束由JAVA程序控制.上次报死锁的过程,抽象如下delimit…