Once a table is created in the database, there are many occasions where one may wish to change the structure of the table. In general, the SQL syntax for ALTER TABLE is, ALTER TABLE "table_name" [alter specification];[alter specification] is dependent on the type of alteration we wish ...
Table of content SQL Databases SQL Database Table Structure Types of SQL Databases MySQL MS SQL Server ORACLE MS ACCESS PostgreSQL SQLite Benefits of Using SQL Database Previous Quiz Next SQL DatabasesSQL or Relational databases are used to store and manage the data objects that are related to ...
How to update a SQL database table structureWe can alter an existing table structure using the ALTER TABLE command, followed by the alteration you want to make:ALTER TABLE people ADD COLUMN born_year INT;This will add a new column with empty values:...
create database 数据库名;-- 创建指定名称的数据库。 create database 数据库名 character set 字符集;-- 创建指定名称的数据库,并且指定字符集(一般都指定 UTF-8)。 Show Database 代码语言:javascript 代码运行次数:0 运行 AI代码解释 --切换数据库 从db1 切换到 db1_1USEdb1_1;--查看当前正在使用的数...
---Table structureforgrade---DROPTABLEIFEXISTS`grade`;CREATETABLE`grade`(`id`int(11)NOTNULLAUTO_INCREMENTCOMMENT'id',`sno`varchar(20)CHARACTERSETutf8COLLATEutf8_unicode_ciNULLDEFAULTNULLCOMMENT'学号',`courseName`varchar(20)CHARACTERSETutf8COLLATEutf8_unicode_ciNULLDEFAULTNULLCOMMENT'课程名',`grade`...
SELECTCASEWHENsc.column_id=1THENso.nameELSE''END表名,CASEWHENsc.column_id=1THENISNULL(pt.value,'')ELSE''END表说明, sc.column_id 字段序号, sc.name 字段名,ISNULL(pc.value,'') 字段说明,CASEWHENCOLUMNPROPERTY(sc.object_id, sc.name,'IsIdentity')=1THEN'√'ELSE''END标识,CASEWHENEXISTS(...
假设我们要导出名为my_database数据库中的表结构: AI检测代码解析 mysqldump-uroot-p--no-data my_database>my_table_structure.sql 1. 执行此命令后,将会要求你输入数据库密码,成功后生成一个名为my_table_structure.sql的文件。 步骤3:查看生成的 SQL 文件 ...
# 创建新数据库cursor.execute("CREATE DATABASE backup_database")# 切换到新数据库cursor.execute("USE backup_database") 1. 2. 3. 4. 5. 4. 备份表结构 接下来,我们需要备份表结构。我们可以使用MySQL的SHOW CREATE TABLE语句来获取表结构的SQL语句。下面是备份表结构的代码示例: ...
In database theory, a table is a structure (“basic unit”) used to store data in the database. I love to use analogies a lot, so I’ll do it here too. If you think of a library, a database is one shelf with books, and each book is a table. Each book has its own contents...
CREATEDATABASE/*!32312 IF NOT EXISTS*/`sg_security`/*!40100 DEFAULT CHARACTER SET utf8mb4*/;USE`sg_security`;/*Table structure for table `sys_menu`*/DROPTABLEIFEXISTS`sys_menu`;CREATETABLE`sys_menu` ( `id`bigint(20)NOTNULLAUTO_INCREMENT, ...