我想从数据库中获取第一条记录该怎么做 [英] i want to fetch 1st record from database how can do that

问题描述

string query1st = "SELECT * FROM Registration_Master ";
                     com = new SqlCommand(query1st, con);
                     com.CommandType = CommandType.Text;
                     SqlDataAdapter da = new SqlDataAdapter(com);
                     DataTable dt1st = new DataTable();
                     da.Fill(dt1st);
                                          
                     if (dt1st.Rows.Count>0)
                     {


                     }

但这给了我错误的输出

添加了代码块[/编辑]

but this gives me wrong output

Code block added[/Edit]

推荐答案

TSQL

TSQL

SELECT TOP 1 * FROM Registration_Master

ORACLE(源 [

ORACLE (source[^])
If you want just a first selected row you can:

select fname from MyTbl where rownum = 1

您还可以使用解析函数对x顶部的x进行排序和取值

you can also use analytic functions to order and take the top x

select max(fname) over (rank() order by some_factor) from MyTbl

MySQL

MySQL

SELECT * FROM Registration_Master LIMIT 1;

但是，如果您想要最新的记录，则在每种情况下都必须根据主键降序(或可以排序以提供最新记录的其他列)对记录进行排序

If you want the latest record however, in each case you will have to order your records based on your primary key descending(or other column that can be sorted to provide the latest record)

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