SQL -- Returns only two of the columns from the tableSELECTProductName, PriceFROMdbo.ProductsGO 使用WHERE子句,限制要傳回給使用者的資料列。 SQL -- Returns only two of the records in the tableSELECTProductID, ProductName, Price, ProductDescriptionFROMdbo.ProductsWHEREProductID <60GO ...
6: insert into @table select S.empid,S.empname,T.deptname,S.salary from Employees s inner join Departments T ON S.deptid =T.deptid 7: SELECT COUNT (empid) ,Department,Salary FROM @table GROUP BY Department,Salary HAVING Salary>2000 8: end 使用临时表: 1: Create procedure Performance_Iss...
TABLE_QUALIFIER TABLE_OWNER TABLE_NAME COLUMN_NAME DATA_TYPE TYPE_NAME PRECISION LENGTH SCALE RADIX NULLABLE REMARKS COLUMN_DEF SQL_DATA_TYPE SQL_DATETIME_SUB CHAR_OCTET_LENGTH ORDINAL_POSITION IS_NULLABLE SS_DATA_TYPE TestDB dbo CUSTOMERS ID 4 int 10 4 0 10 0 NULL NULL 4 NULL NULL 1 NO...
执行以下语句创建一个视图,该视图执行 Select 语句,并将产品的名称和价格返回给用户。 SQL CREATEVIEWvw_NamesASSELECTProductName, PriceFROMProducts; GO 测试视图 视图的处理方式与表类似。 使用SELECT语句访问视图。 SQL SELECT*FROMvw_Names; GO 创建存储过程 ...
IF@PkColumnISNULLSELECT@PkColumn=N'cast(NULL as nvarchar(max))';-- set select statement using dynamic UNPIVOTDECLARE@SQLNVARCHAR(MAX);SET@SQL=N'select *, '+QUOTENAME(@Table_Schema,''')+N'as [Table Schema], '+QUOTENAME(@Table_Name,''')+N' as [Table Name]'+N' from (select...
本文详细介绍了T-SQL中的INSERT、UPDATE、DELETE和SELECT语句的语法及示例,涵盖了单条和批量数据插入、数据更新、删除操作以及复杂查询技巧,包括嵌套查询、联接查询和结果集组合等,帮助读者掌握数据库操作的基本方法和高级应用。
练习一:使用ALTER TABLE来添加和修改列 Examine the following CREATE TABLE statement, from the TSQL2012.sql script, that is used to create the Production.Categories table. 从TSQL2012.sql脚本开始,测试下面的CREATE TABLE语句,它是用来创建一个Production.Categories表。
SQLSELECT * FROM sys.key_constraints WHERE type = 'PK' Also you can find the unique index that SQL Server uses to enforce a primary key constraint by querying sys.indexes. For example, the following query shows the unique index declared on the Production.Categories table for the PK_Categorie...
Let’s first create the schema Grade3 using the T-SQL CREATE SCHEMA statement and execute the following query to have a table created in the specified database and schema. USE AdventureWorksDW2017 GO CREATE SCHEMA Grade3; DROP TABLE IF EXISTS AdventureWorksDW2017.Grade3.Grade3Students ...
It turns out that the query requires a minor change, as the XML schema and the name for the ring buffer has changed in SQL 2012. The new name for the ring buffer is RING_BUFFER_SPACEMGR_TRACE. And here is the modified query, reflecting changes in the XML schema as well: SELECT top...