record deleting from sql server

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SqlConnection con=new SqlConnection ("connectionstring");
        con.Open ();
        SqlCommand cmd = new SqlCommand("select count(*) from tableName where cid=1233", con);
        int i = 0;
        i=(int)cmd.ExecuteScalar();
        if (i > 0)
        {
            //record is available
            SqlCommand deleteCmd = new SqlCommand("delete tablename where cid=1233", con);
            int res = 0;
            res=deleteCmd.ExecuteNonQuery();
            if (res > 0)
            {
                //deleted successfully
            }
            else
            {
                //failed to delete
            }
        }
        else
        {
            //there is no record
        }

here is the problem
i=(int)cmd.ExecuteScalar();

every time me getting i > 0 false

Posted 26-Jul-11 21:46pm

kami124

Updated 26-Jul-11 21:47pm

Manas Bhardwaj

v2

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3 solutions

Solution 1

This means the query

select count(*) from tableName where cid=1233

always returns 0. Check if there are any records in database with this condition.

Posted 26-Jul-11 21:51pm

Manas Bhardwaj

Comments

kami124 27-Jul-11 4:41am

still there is problem its executing
i=(int)cmd.ExecuteScalar();
and the value of i become -1

Solution 4

Hi,
in query where condition must and should satisfy then oly u will get i=1 ,just give valid connectionstring and valid query

Posted 26-Jul-11 22:51pm

Tajuddin_HYD

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Mohammad A Rahman · Accepted Answer · 2011-07-26T22:45:00

Solution 3

You would need to fix in the below line,

SqlConnection con=new SqlConnection ("connectionstring");

SqlConnection needs a connection string where as you are passing "connectionstring" which is not a valid connection string for SqlConnection.

For your ref,

sqlconnection[^]

connectionstrings/[^]

sqlconnection-connection-string.aspx[^]

Hope it helps :)

Posted 26-Jul-11 22:45pm

Mohammad A Rahman

Updated 26-Jul-11 22:52pm

v2

Comments

kami124 27-Jul-11 4:52am

please come on its just example i wrote it in proper way there is no problem in the string

the problem is executing i=(int)cmd.ExecuteScalar(); and the value of i become -1

Mohammad A Rahman 27-Jul-11 4:57am

Please post the code you are using, instead of example code.

kami124 27-Jul-11 5:11am

here is my code

public static void function_sql_connection_delete(string str_querry, string str_querry1, string str_id)
{
try
{

int count = 0;

sql_string = ("Data Source=aaa.asd.fdsf.gfhfg;Initial Catalog=sdfsdC;User Id=fghgfh;Password=gfhfghf");
SqlConnection conn = new SqlConnection(sql_string);
conn.Open();
SqlCommand command = conn.CreateCommand();
command.CommandText = (str_querry1);
int i = 0;

i = (int)command.ExecuteNonQuery();
if (i != 0)
{
MessageBox.Show("Record is Present in data base");

SqlCommand deleteCmd = new SqlCommand(str_querry, conn);
int res = 0;
res = deleteCmd.ExecuteNonQuery();
if (res > 0)
{

MessageBox.Show("Record is deleted Successfully");
count++;
conn.Close();

}
else
{

MessageBox.Show("Failed to delete the Record");
conn.Close();
}
}
else
{

MessageBox.Show("There is no such Record present in the List");
conn.Close();
}

}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
MessageBox.Show("Error in database connection");
}
}

kami124 27-Jul-11 5:12am

here are the querries
sql_querry_string1 = "SELECT count(*) FROM sec_users WHERE (userid_vc) = ('" + (textBoxUserId.Text.Trim()) + "')";
sql_querry_string = "DELETE FROM sec_users WHERE (userid_vc) = ('" + (textBoxUserId.Text.Trim()) + "')";

Mohammad A Rahman 27-Jul-11 5:36am

Following code needs to change,

SqlCommand command = conn.CreateCommand();
command.CommandText = (str_querry1);
int i = 0;

i = (int)command.ExecuteNonQuery();
if (i != 0)

as

SqlCommand command = conn.CreateCommand();
command.CommandText = (str_querry1);
command.Connection = conn;
int i = 0;

i = (int)command.ExecuteScalar();
if (i != 0)
{
....

Hope it works

kami124 27-Jul-11 6:01am

i change it but still the same problem

Mohammad A Rahman 27-Jul-11 6:04am

Can you please try this,

SqlCommand command = conn.CreateCommand();
command.CommandText = "SELECT count(*) FROM sec_users";
command.Connection = conn;
int i = 0;

i = (int)command.ExecuteScalar();
if (i != 0)
{
....

kami124 27-Jul-11 6:28am

ok nice
thanks alot its mean for command.commandText i have to write direct querry not any styored querry
ok thanks