Code:
$
$
$ # show the content of the input file "f1"
$ cat -n f1
1 KSA,B12467428,2010-06-04,2010-06-04,2011-06-04,ITI, ,N,2011-06-04,AT,IFGC,13097573, ,001,OUT,1, 0000000000627.00, , , , 0000000000000.00, ,,, -0000000000627.00, 0000000000000.00, 0000000000532.95, 0000000000094.05, 00000.1500, 0000000000000.00
2 KSA,M03201053,2009-06-11,2009-06-11,2010-06-11,IMP,P,R,2010-06-11,ME,IFGC,06490230, ,013,XLL,1,-0000000000657.00, , , , 0000000000000.00, ,,,-0000000000657.00, 0000000000000.00,-0000000000545.31,-0000000000111.69, 00000.0000, 0000000000000.00
3 2009-09-09,KSA,M03201053,2009-06-11,2010-06-11,IMP,P,R,2010-06-11,ME,IFGC,06490230, ,013,XLL,1,-0000000000657.00, , , , 0000000000000.00, ,,,-0000000000657.00, 0000000000000.00,-0000000000545.31,-0000000000111.69, 00000.0000, 0000000000000.00
4 KSA,M03201053,2009-06-11,2009-06-11,2010-06-11,IMP,P,R,2010-06-11,ME,IFGC,06490230, ,013,XLL,1,-0000000000657.00, , , , 0000000000000.00, ,,,-0000000000657.00, 0000000000000.00,-0000000000545.31,-0000000000111.69, 00000.0000,2010-12-31
$
$
$ # run the Perl one-liner to transform the dates
$ perl -lne 's/(^|,)(\d{4})-(\d\d)-(\d\d)/$1$2$3$4/g; print' f1
KSA,B12467428,20100604,20100604,20110604,ITI, ,N,20110604,AT,IFGC,13097573, ,001,OUT,1, 0000000000627.00, , , , 0000000000000.00, ,,, -0000000000627.00, 0000000000000.00, 0000000000532.95, 0000000000094.05, 00000.1500, 0000000000000.00
KSA,M03201053,20090611,20090611,20100611,IMP,P,R,20100611,ME,IFGC,06490230, ,013,XLL,1,-0000000000657.00, , , , 0000000000000.00, ,,,-0000000000657.00, 0000000000000.00,-0000000000545.31,-0000000000111.69, 00000.0000, 0000000000000.00
20090909,KSA,M03201053,20090611,20100611,IMP,P,R,20100611,ME,IFGC,06490230, ,013,XLL,1,-0000000000657.00, , , , 0000000000000.00, ,,,-0000000000657.00, 0000000000000.00,-0000000000545.31,-0000000000111.69, 00000.0000, 0000000000000.00
KSA,M03201053,20090611,20090611,20100611,IMP,P,R,20100611,ME,IFGC,06490230, ,013,XLL,1,-0000000000657.00, , , , 0000000000000.00, ,,,-0000000000657.00, 0000000000000.00,-0000000000545.31,-0000000000111.69, 00000.0000,20101231
$
$