代码语言:sql 复制 SELECT * FROM Customers FETCH FIRST 3 ROWS ONLY; 使用旧版 Oracle 的 ROWNUM 以下SQL 语句展示了旧版 Oracle 的等效示例: 选择"Customers" 表的前 3 条记录: 代码语言:sql 复制 SELECT * FROM Customers WHERE ROWNUM <= 3; 添加WHERE 子句 以下SQL 语句从 "Customers" 表中选择前三...
FETCH FIRST 5 ROWS ONLY就会按字面的意思去做的(只取前 5 行)。 如果你使用 Oracle,需要基于ROWNUM(行计数器)来计算行,像这样: SELECTprod_name FROMProducts WHEREROWNUM<=5; 如果你使用 MySQL、MariaDB、PostgreSQL 或者 SQLite,需要使用LIMIT子句,像这样: SELECTprod_name FROMProducts LIMIT5; 上述代码使用S...
lnameVARCHAR(20));SELECTidAS"编号",nameAS"姓名"FROMt_stu; #起别名时,as可以省略SELECTidAS编号,nameAS姓名FROMt_stu; #别名中没有空格时,""可以省略SELECTidAS编 号,nameAS"姓名"FROMt_stu; #错误,别名中有空格时,""不可以省略SELECTidAS"编号",nameAS"姓名"FROMt_stu; #这一条才最符合SQL编写规范...
LIMIT3; Try it Yourself » The following SQL statement shows the equivalent example for Oracle: Example SELECT*FROMCustomers ORDERBYCustomerNameDESC FETCHFIRST3ROWS ONLY; Exercise? What would the following query do in SQL Server? SELECT TOP 5 * FROM Customers; ...
Learn more about the Microsoft.VisualStudio.Imaging.KnownMonikers.SelectAllRowsFromLeftTable in the Microsoft.VisualStudio.Imaging namespace.
{ FIRST | LAST } ]} [, ...] ] [ { [ LIMIT { count | ALL } ] [ OFFSET start [ ROW | ROWS ] ] } | { LIMIT start, { count | ALL } } ] [ FETCH { FIRST | NEXT } [ count ] { ROW | ROWS } ONLY ] [ {FOR { UPDATE | SHARE } [ OF table_name [, ...] ] [...
SqlDataSource 构造函数 属性 方法 CreateDataSourceView 删除 GetDbProviderFactory GetView GetViewNames 插入 LoadViewState OnInit SaveViewState Select TrackViewState 更新 事件 SqlDataSourceCommandEventArgs SqlDataSourceCommandEventHandler SqlDataSourceCommandType ...
WHERE FNumber NOT IN (SELECT FNumber FROM T_Employee ORDER BY FSalary DESC FETCH FIRST 5 ROWS ONLY )ORDER BY FSalary DESC FETCH FIRST 3 ROWS ONLY 抑制数据重复 DISTINCT DISTINCT关键字是用来进行重复数据抑制的最简单的功能，而且所有的数据库系统都支持DISTINCT，DISTINCT的使用也非常简单，...
SQL ORDER BY OrderDate DESC; Now that you've seen what each clause does, let's look at the order in which SQL Server actually evaluates them: The FROM clause is evaluated first, to provide the source rows for the rest of the statement. A virtual table is created and passed to the ne...
Sorting Rows with ORDER BY Subquery Fundamentals Join Fundamentals Manipulating Result Sets Changing Data in a Database Procedural Transact-SQL Transactions (Database Engine) Locking and Row Versioning Cursors (Database Engine) Distributed Queries