PGresult and for-cycle

I develop this code:
PQclear(sol);psqlDisconnettiDB(DB);
ris=(abbonamenti_t **) calloc(nabb,sizeof(abbonamenti_t *));sol2=(PGresult **) calloc(nabb,sizeof(PGresult *));
for (i=0;ilire_abb=atof(PQgetvalue(sol2[i],i,0));   ris[i]->euro_abb=atof(PQgetvalue(sol2[i],i,1));   ris[i]->inizio_abb=astrcpy(PQgetvalue(sol2[i],i,2));   ris[i]->fine_abb=astrcpy(PQgetvalue(sol2[i],i,3));   ris[i]->abbo=astrcpy(PQgetvalue(sol2[i],i,4));
   PQclear(sol2[i]);   psqlDisconnettiDB(DB);}

the 1st loop is OK, the 2nd produces a core and stops at /***/.
Why ?

Could you help me ?
-----------------------------------
Gianluigi  Roveda
E-mail: roveda@omega.it

Omega Generation S.R.L.
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