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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...
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;
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 ...
应用对象SQL Server 2012 Service Pack 3 SQL Server 2014 Developer - duplicate (do not use) SQL Server 2014 Enterprise - duplicate (do not use) SQL Server 2014 Enterprise Core - duplicate (do not use) SQL Server 2014 Standard - duplicate (do not use) SQL Server 2016 Develo...
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...
In MySQL Version 3.22 or later, you can use the keywordsIF EXISTSto prevent an error from occurring if the database doesn’t exist. You can also drop databases withmysqladmin. SeeSection 4.8. CREATE TABLESyntax CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name [(create_definition,...)]...