常用的sql语句

delete from st where id='" + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'"

string sqlStr = "select * from st  where  id =''  ";

  string commdstr = "insert into st(id,name,date,action) values('" + TextBox1.Text + "','" + TextBox2.Text + "','" + TextBox3.Text + "','" + TextBox4.Text + "')";  

update st set id='" + id + "', name='" + name + "' , date='" + date + "' , action='" + action + "'  where id='" + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'"