एक SQL क्वेरी

Question

सी # (.cs फ़ाइल) में सबसे आसान तरीका क्या है एक int चर में एसक्यूएल आदेश

SELECT COUNT(*) FROM table_name 

से गणना प्राप्त करने से गिनती कैप्चरिंग?

Answer 1

उपयोग SqlCommand.ExecuteScalar() और यह एक int लिए डाली:

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

Answer 2

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

Answer 3

तुम साथ

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

उपयोग बजाय

 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 ; 
     } 

Answer 4

एसक्यूएल के साथ सी # में पूरक त्रुटियों परिवर्तित मिलती है:

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