:start                            ; branching target "start"
/^$/ b print                      ; if we find an empty line, go to "print"
$    b print                      ; if it is the last line, go to "print"
H                                 ; otherwise: append line to hold space
d                                 ;       and delete it from pattern space
b start                           ;       then goto "start" (start over)
:print                            ; start of "print" subroutine
    {
      g                           ; copy hold space to pattern space
      s/\n/ /g                    ; remove all newline characters
      s/select.*//                ; the remove "select" and everything after
      s/^ *//                     ; remove eventually leading space
      s/  */ /g                   ; replace multiple spaces by a single one
      s/Locking/& row/            ; "Locking" -> "Locking row"
      s/Access/access/            ; "Access" -> "access"
      p                           ; finally print it
      g                           ; copy the hold space again
      s/.*select/select/p         ; remove everything before "select", print
      d                           ; delete pattern space
      h                           ; and copy it to hold space, thus clearing it
    }

sed -f /path/to/scriptfile /path/to/input > /path/to/output

      s/Access/access/            ; "Access" -> "access"
      p                           ; finally print it