[SQL] SQL 쿼리에서 카운트를 캡처

SQL 쿼리에서 카운트를 캡처

SQL 명령의 수를 얻기 위해 C #을 (.cs 파일)에있는 가장 간단한 방법은 무엇입니까

SELECT COUNT(*) FROM table_name

int 형 변수로?

해결법

1. ==============================

   1.사용 SqlCommand.ExecuteScalar () 및 int로 캐스팅 :

   사용 SqlCommand.ExecuteScalar () 및 int로 캐스팅 :

   cmd.CommandText = "SELECT COUNT(*) FROM table_name";
   Int32 count = (Int32) cmd.ExecuteScalar();
   

2. ==============================

   2.

   SqlConnection conn = new SqlConnection("ConnectionString");
   conn.Open();
   SqlCommand comm = new SqlCommand("SELECT COUNT(*) FROM table_name", conn);
   Int32 count = (Int32) comm .ExecuteScalar();
   

3. ==============================

   3.당신과 오류를 변환 얻을 것이다 :

   당신과 오류를 변환 얻을 것이다 :

   cmd.CommandText = "SELECT COUNT(*) FROM table_name";
   Int32 count = (Int32) cmd.ExecuteScalar();
   

   대신 사용

   string stm = "SELECT COUNT(*) FROM table_name WHERE id="+id+";";
   MySqlCommand cmd = new MySqlCommand(stm, conn);
   Int32 count = Convert.ToInt32(cmd.ExecuteScalar());
   if(count > 0){
       found = true; 
   } else {
       found = false; 
   }
   

4. ==============================

   4.SQL과 C #으로 보완 :

   SQL과 C #으로 보완 :

   SqlConnection conn = new SqlConnection("ConnectionString");
   conn.Open();
   SqlCommand comm = new SqlCommand("SELECT COUNT(*) FROM table_name", conn);
   Int32 count = Convert.ToInt32(comm.ExecuteScalar());
   if (count > 0)
   {
       lblCount.Text = Convert.ToString(count.ToString()); //For example a Label
   }
   else
   {
       lblCount.Text = "0";
   }
   conn.Close(); //Remember close the connection
   

5. ==============================

   5.

   int count = 0;    
   using (new SqlConnection connection = new SqlConnection("connectionString"))
   {
       sqlCommand cmd = new SqlCommand("SELECT COUNT(*) FROM table_name", connection);
       connection.Open();
       count = (int32)cmd.ExecuteScalar();
   }
   

from https://stackoverflow.com/questions/4668911/capturing-count-from-an-sql-query by cc-by-sa and MIT license