Updating column in access DB after getting which DataGridView CheckBoxes are selected in VB.net -

i starting in vb.net , trying update row in access database selected datagridview checkbox in vb.net.

here part of system:

here code:

private sub editio_linkclicked(byval sender system.object, byval e system.windows.forms.linklabellinkclickedeventargs) handles editio.linkclicked          if myconnection.state = connectionstate.open             myconnection.close()         end if         myconnection.connectionstring = connstring         myconnection.open()           if editio.text = "enable time in/out edit"             try                 dim checkedrows =                     (                         rows in admintabdisplay.rows.cast(of datagridviewrow)()                         cbool(rows.cells("ck").value) = true                     ).tolist                 if checkedrows.count > 0                      dim sb new system.text.stringbuilder                     each row datagridviewrow in checkedrows                         sb.appendline(row.cells("last name").value.tostring)                      next                     dim cmd oledbcommand = new oledbcommand("update [roster1] set [edittime] = 'e' [last name] = '" & sb.tostring & "'", myconnection)                     dim dr oledbdatareader = cmd.executereader                     end if             catch ex exception                 messagebox.show(ex.message)             end try         end if         viewadmin()         editio.text = "disable time in/out edit"     end sub 

it can check checkboxes selected , can update whole database when link clicked.

but every time add "where" clause after db command (which "where [last name] = '" & sb.tostring & "'"), doesn't update selected row.

also, use "employee id" column in replacement of "last name" column used in clause

if possible, please explain simple can be. i'm still beginner in vb.net. thank much! every appreciated!

never mind post. solved tiny detail.

i used "employee id" column instead of "last name" column shown in code above

it converted string (because of stringbuilder). converted integer code:

           dim sb new system.text.stringbuilder            each row datagridviewrow in checkedrows                 sb.appendline(row.cells("last name").value.tostring)             next                     dim st string = sb.tostring                 dim value integer = cint(st) 

and changed database command to:

                dim cmd oledbcommand = new oledbcommand("update [roster1] set [edittime] = 'e' [employee id] = " & value & "", myconnection)                 dim dr oledbdatareader = cmd.executereader