mysql> CREATE TABLE userlist2 //参照userlist表结构建立新表 -> SELECT * FROM userlist WHERE FALSE; Query OK, 0 rows affected (0.48 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> SELECT * FROM userlist2; //确认新表userlist2无任何记录 Empty set (0.00 sec) mysql> LOAD DATA INFILE ...
SELECT INTO: 从一个表中选择数据,然后将这些数据插入到另一个表中去。通常用于备份表。 选择所有列: Syntax: SELECT * INTO new_table_name [IN externaldatabase] FROM old_tablename Example: SELECT * INTO Persons_Backup IN 'Backup.mdb' FROM Persons 选择若干列: Syntax: SELECT column_name(s) INTO...
Considering the database above, use SQL language to write the following queries. Solution Q1. Find the department names of all instructors 代码语言:javascript 代码运行次数:0 运行 AI代码解释 select distinct dept_name from instructor; Q2. Find the names of all instructors in the Computer Science ...
SELECT[name], compatibility_levelFROMsys.databases; To determine the version of the Database Engine that you're connected to, execute the following query. SQL SELECTSERVERPROPERTY('ProductVersion'); Compatibility levels and database engine upgrades ...
稍后我们将详细介绍表达式和内置函数,本例是想让你大致了解select子句中可以包含哪些内容。如果你只需要执行内置函数或计算简单表达式,可以完全跳过from子句。举个例子: mysql> SELECT version(), -> user(), -> database(); +---+---+---+ | version() | user() | database() | +---+---+---+...
This name should be unique among all the Database_Directory names in the SQL Server instance. Uniqueness comparison is case-insensitive, regardless of SQL Server collation settings. This option should be set before you create a FileTable in this database. The f...
This name should be unique among all the Database_Directory names in the SQL Server instance. Uniqueness comparison is case-insensitive, regardless of SQL Server collation settings. This option should be set before you create a FileTable in this database. The following options are allowable only...
If the ALTER DATABASE statement doesn't complete in a timely manner, check to see if other sessions within the database are blocking the ALTER DATABASE session. For more information about the syntax conventions, see Transact-SQL syntax conventions. Select a product In the following row, select...
"explicit value must be specified for identity column in table" error in SQL 2000 "FROM clause have the same exposed names. Use correlation names to distinguish them" "No transaction is active." error when trying to send a transactional SQL statment over MSDTC "Restricted data type attr...
简易说明 在MySQL中创建数据库语法:create database db_name。而在Oracle数据库中创建数据库语法create user db_name,你没看错,Oracle中基于用户进行描述与管理。如果你在Oracle中使用create database db_name,会提示数据库已装载。 表 表(table):某种特定类型数据库结构化清单。 表名 表名(table name):表名是...