TABLE_CATALOG nvarchar(128) 數據表限定符。 TABLE_SCHEMA nvarchar(128) 包含數據表的架構名稱。 重要: 尋找物件架構的唯一可靠方式是查詢 sys.objects 目錄檢視。 TABLE_NAME sysname 資料表名稱。 CONSTRAINT_TYPE varchar(11) 條件約束的類型: CHECK UNIQUE PRIMARY KEY FOREIGN KEY IS_DEFERR...
本文转自:https://stackoverflow.com/questions/14229277/sql-server-2008-get-table-constraints You should use the currentsyscatalog views (if you're on SQL Server2005or newer - thesysobjectsviews aredeprecatedand should be avoided) - check out theextensive MSDN SQL Server Books Online documentation ...
publicvoidAddUniqueConstraint(stringtableName,stringcolumnName){stringquery=$"ALTER TABLE{tableName}ADD CONSTRAINT UQ_{columnName}UNIQUE ({columnName})";// 执行 SQL 语句} 1. 2. 3. 4. 5. 生态集成 在考虑生态集成时,我制作了类图和扩展模块的关系图,以确保新约束在整体架构中的合理性: 使用Databas...
SQL Server 2022 (16.x) introduces resumable operations for adding table constraints for primary key and unique key constraints. For more information on enabling and using resumableALTER TABLE ADD CONSTRAINToperations, seeResumable add table constraints. ...
UNIQUE constraints default to NONCLUSTERED.If a clustered constraint or index already exists on a table, CLUSTERED cannot be specified. If a clustered constraint or index already exists on a table, PRIMARY KEY constraints default to NONCLUSTERED....
The number of rows in the table is limited only by the storage capacity of the server. You can assign properties to the table and to each column in the table to control the data that is allowed and other properties. For example, you can create constraints on a column to disallow null ...
本文将要的介绍的内容包括:SQL Server三种不同类型的Hints:联接提示(Join Hints)、查询提示(Query Hints)、表提示(Table Hints),包括SQL Server2008中引入的提示ForceSeek,可以用它将索引查找来替换索引扫描。 1、使用联接提示(Join Hints) 官方解释:联接提示用于指定查询优化器在两个表之间强制执行联接策略。(http:/...
You can validate the NOT NULL constraints using the SSMS table designer as well. UNIQUE constraint The UNIQUE constraint in SQL Server ensures that you do not have duplicate values in a single column or combination of columns. These columns should be part of the UNIQUE constraints. SQL Server ...
SQL Server / Oracle / MS Access: CREATETABLEPersons(Id_PintNOTNULLUNIQUE,LastNamevarchar(255)NOTNULL,FirstNamevarchar(255),Addressvarchar(255),Cityvarchar(255)) 1. 2. 3. 4. 5. 6. 7. 8. 如果需要命名 UNIQUE 约束,以及为多个列定义 UNIQUE 约束,请使用下面的 SQL 语法: ...
These constraints create indexes. If filegroup is specified, the index is stored in the named filegroup. If "default" is specified, or if ON isn't specified at all, the index is stored in the same filegroup as the table. If the PRIMARY KEY or UNIQUE constraint creates a clustered index,...