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Flink SQL> show databases; +---+ | database name | +---+ | default_database | | alan_test | +---+ 2 rows in set Flink SQL> ALTER database default_catalog.alan_test set('createdate'='2023-11-20'); [INFO] Execute statement succeed. Flink SQL> show databases; +---+ | data...
5. 选择数据库 进入数据库:use db_name; 查看当前所选的数据库: select database(); b. 操作表 1. 创建表 创建一个员工表employee create table employee( id int primary key auto_increment, name varchar(20) unique, gender bit not null, birthday date, entry_date date, job varchar(40), salary...
To see the details about all indexes in a database, use thesys.indexescatalog view. Azure SQL Database supports the three-part name format:database_name.schema_name.object_namewhendatabase_nameis the current database, or the database_name istempdbandobject_namestarts with#or##. ...
SQL DROPTABLEAdventureWorks2022.dbo.SalesPerson2 ; C. Dropping a temporary table The following example creates a temporary table, tests for its existence, drops it, and tests again for its existence by attempting to execute aSELECTstatement, which fails. This example doesn't use theIF EXISTSsynta...
SQL -- This script uses sqlcmd scripting variables. They are in the form-- $(MyVariable). For information about how to use scripting variables-- on the command line and in SQL Server Management Studio, see the-- "Executing Replication Scripts" section in the topic-- "Programming Replication...
In the Server name box, type the name of the server that contains the SQL Server database. Under Log on credentials, do one of the following: If the database determines who has access based on the credentials used in a Microsoft Wi...
Built-in system objects and extensions Control-of-flow language Data definition language (DDL) statements Introduction to DDL Securing meta data objects U-SQL databases U-SQL database schemas Introduction to database schemas CREATE SCHEMA USE SCHEMA ...
How to Delete Table in SQL? When we use the DELETE statement without the WHERE clause, all table rows shall be deleted, but the table structure will remain the same. The syntax for the same is as below: DELETE FROM table_name;
SQL Server 2008中的临时表有两种类型,本地临时表和全局临时表。本地临时表只有创建者可以看见并使用,在创建者与SQL Server实例断开连接后,系统会自动删除本地临时表。全局临时表在创建后,对任何用户和任何连接来说,都是可见的,当引用该表的所有用户都与SQL Server实例断开连接后,系统才会将该表删除。