    hash = core_hash(dbn, tbn, DBCASSA_TABLE_SIZE);
    **if(!hash)
            LM_ERR("hash  NOT FOUND\n");**
    hashidx = hash % DBCASSA_TABLE_SIZE;
    **if(!hashidx)
            LM_ERR("hashidx NOT FOUND\n");**
    ref_read_data(dbcassa_tbl_htable[hashidx].lock);

    tbc = dbcassa_tbl_htable[hashidx].dtp;
    **if(!tbc)
            LM_ERR("TBC NOT FOUND\n");**
    while(tbc) {
            LM_DBG("found dbname=%.*s, table=%.*s\n", tbc->dbname.len, tbc->dbname.s, tbc->name.len, tbc->name.s);
            if(tbc->hash==hash && tbc->dbname.len == dbn->len
                            && tbc->name.len == tbn->len
                            && !strncasecmp(tbc->dbname.s, dbn->s, dbn->len)
                            && !strncasecmp(tbc->name.s, tbn->s, tbn->len)) {

                    memcpy(full_path_buf + dbcassa_schema_path.len, dbn->s, dbn->len);
                    len = dbcassa_schema_path.len + dbn->len;
                    full_path_buf[len++] = '/';
                    memcpy(full_path_buf + len, tbn->s, tbn->len);
                    full_path_buf[len + tbn->len] = '\0';

                    if(dbcassa_check_mtime(&tbc->mt) == 0)
                            return tbc;
                    old_tbc = tbc;
                    break;
            }
            tbc = tbc->next;
    }
    unref_read_data(dbcassa_tbl_htable[hashidx].lock);
    **if(!old_tbc) {
            LM_ERR("OLD_TBC NOT FOUND\n");**
            return NULL;
    }