party leader from to
party
leader
from
to
number parsed year month
number parsed year month
text text date date
scottish national party gordon wallace may 1974 may 1978
how many parties had the same leader in office twice ?
WRB JJ NNS VBD-AUX DT JJ NN IN NN RB .
1
select count ( distinct c1 ) from w group by c2 having count ( c2 ) = 2