Question

vb.net 查询sql表中某一列的数据

比如我想查询下面这个表中User这个列是否存在“123”这个数据，请问这样一个vb.net代码怎么写？谢谢

Answer 1

Dim blUser As Boolean
Dim sql_conn As New SqlClient.SqlConnection("data source=.;initial catalog=test;user id=sa;password=123456;")
sql_conn.Open()
Dim sql_comm As New SqlClient.SqlCommand("Select user from table where user='123'", sql_conn)
Dim reader As SqlClient.SqlDataReader
reader = sql_comm.ExecuteReader
reader.Read()
If reader.HasRows Then
blUser = True
End If
reader.Close()
sql_conn.Close()

Answer 2

select * from table where User='123'