如何从主表中获取最大id，并基于此，在主表中插入一条记录，在子表中插入一个或多个条目

Question

When I click on add that data will go to child table and above data go to master table.

Here's a screenshot of the design:

save button click event:

 protected void btnsave_Click(object sender, EventArgs e)
    {
        SqlConnection con2 = new SqlConnection(@"Data Source=GLSPL06-PC\GLSPL06;Initial Catalog=example;User ID=sa;Password=sa@123");
        con2.Open();
        SqlCommand cd = new SqlCommand("insertmaster", con2);
        cd.CommandType = CommandType.StoredProcedure;
        cd.Parameters.AddWithValue("@name", txtname.Text.Trim());
        cd.Parameters.AddWithValue("@age", txtage.Text.Trim());
        cd.Parameters.AddWithValue("@gender", Radiogender.SelectedItem.ToString());
        cd.ExecuteNonQuery();
        con2.Close();

        foreach (GridViewRow item in gv.Rows)
        {


            SqlConnection con = new SqlConnection(@"Data Source=GLSPL06-PC\GLSPL06;Initial Catalog=example;User ID=sa;Password=sa@123");
            con.Open();
            string statment = string.Format("insert into  child_table ( [relative_name], [relation]) values ('{0}','{1}')", item.Cells[0].Text, item.Cells[1].Text);
            SqlCommand cmd = new SqlCommand(statment, con);
            cmd.CommandType = CommandType.Text;
            cmd.ExecuteNonQuery();
            con.Close();

        }

        successmsg.Text = "Data Inserted Successfully";
    }

Answer 1

You have to write Sql query as below in your procedure and call your procedure from application:

 DECLARE @id INT
    INSERT INTO MainPerson VALUES(Name,Age,Male)
    SET @id= SCOPE_IDENTITY()
    INSERT  INTO RelativePerson Values(@id,Name,Relation)

As you have to use the Scope_Identity in order to get the last id inserted to your master table.

Answer 2

Change Your code to this:

SqlConnection con2 = new SqlConnection(@"Data Source=GLSPL06-PC\GLSPL06;Initial Catalog=example;User ID=sa;Password=sa@123");
con2.Open();
SqlCommand cd = new SqlCommand("insertmaster", con2);
cd.CommandType = CommandType.StoredProcedure;
cd.Parameters.AddWithValue("@name", txtname.Text.Trim());
cd.Parameters.AddWithValue("@age", txtage.Text.Trim());
cd.Parameters.AddWithValue("@gender", Radiogender.SelectedItem.ToString());
string id = cd.GetScalar();
con2.Close();

And Change Your insertmaster Procedure to:

Insert into MainTable values(name,age,gender)
Select SCOPE_IDENTITY()

Then you will get the id use that to insert in child table from code.