Fórum select com distinct #163027

Pq quando acrescento o [b:d4c3d58e52]distinct[/b:d4c3d58e52] dar erro no código abaixo??

Select distinct
substring(ger_cg.cg_cd,1,10) ´Codigo´,
substring(cg_nm,1,25) ´Nome´
from ger_cg,ger_nfs
where ger_cg.cg_cd = ger_nfs.cg_cd and
ger_nfs.nf_dtcanc is null and
ger_nfs.nf_dtemis between ´2002-01-21´ and ´2003-01-30´
order by ger_cg.cg_nm[/b]