Problem about put and get

Question

hi there,
I met a problem, when i put the data, and get it.
key data
aaa aaaaaa
bbb bbbbbb
ccc cccccc
I have put "aaa", "bbb" and "ccc" into db, but when I try to get the key for "aaa" , "bbb", it return the data "cccccc", how can I solve it?
after that, when i get the key "ddd", "eee" , and all strings are length 3, the key does not in the DB, it also return the data "cccccc". Did I do something wrong on my code?
void Set1(CString sKey)
int ret;
std::string sdb = "test.db";
Db db(NULL, 0);
ret = db.open(NULL,
     sdb.c_str(),
     NULL,
     DB_BTREE,
DB_CREATE,
     0);
std::string skey, sdata;
skey = sKey;
sdata.append(skey);
sdata.append(skey);
Dbt key(&skey, skey.length());
Dbt data(&sdata, sdata.length());
ret = db.put(NULL, &key, &data, 0);
if(ret==0){
TRACE("success\n");
ret = db.close(0);
void Get1(CString sKey)
int ret;
std::string sdb = "test.db";
ret = db.open(NULL,
sdb.c_str(),
     NULL,
     DB_BTREE,
     DB_CREATE,
     0);
Dbc *cur;
ret = db.cursor(NULL, &cur, 0);
std::string skey, s2, a2;
skey = sKey;
Dbt key(&skey, skey.length());
Dbt data;
memset(&data, 0, sizeof(data));
ret = cur->get(&key, &data, DB_SET);
if(ret!=DB_NOTFOUND){
a2 = (std::string*) data.get_data();
s2 = (std::string*) key.get_data();
TRACE("FOUND %s %s\n", s2->c_str(), a2->c_str());
ret = cur->close();
ret = db.close(0);
}

Answer 1

Hi,
The problem seems to be with these lines:
std::string skey, sdata;
Dbt key(&skey, skey.length());
Dbt data(&sdata, sdata.length());You are constructing a Dbt with data that is actually a pointer to a C++ std::string object. You want the value to be an actual c style string.
An alternative would be to construct the Dbts like:
Dbt key(skey.c_str(), skey.length());
Dbt data(sdata.c_str(), sdata.length());You will need to create a new std::string out of any data retrieved from the database as well. Since it will now be just a C-style char * string.
I hope this helps.
Regards,
Alex Gorrod, Oracle