本文整理汇总了C++中Dbc::pget方法的典型用法代码示例。如果您正苦于以下问题：C++ Dbc::pget方法的具体用法？C++ Dbc::pget怎么用？C++ Dbc::pget使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类Dbc的用法示例。
在下文中一共展示了Dbc::pget方法的4个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: children
Records Database::children(const RecordID& idParent) const
{
Records result;
Dbc* pCursor = nullptr;
dbParentId_.cursor(NULL, &pCursor, 0);
assert(pCursor);
BOOST_SCOPE_EXIT(&pCursor)
{
pCursor->close();
} BOOST_SCOPE_EXIT_END
Dbt keyParent(idParent.data(), idParent.size());
Dbt keyChild;
Dbt record;
int res = pCursor->pget(&keyParent, &keyChild, &record, DB_SET);
while (res == 0)
{
result.push_back(make_Record(RecordID(keyChild), RecordData(record)));
res = pCursor->pget(&keyParent, &keyChild, &record, DB_NEXT_DUP);
}
return result;
}示例2: del
void Database::del(const RecordID& id)
{
Dbt key(id.data(), id.size());
// fetch children
std::vector<RecordID> childrenIds;
Dbc* pCursor = nullptr;
dbParentId_.cursor(NULL, &pCursor, 0);
assert(pCursor);
BOOST_SCOPE_EXIT(&pCursor)
{
if(pCursor) pCursor->close();
} BOOST_SCOPE_EXIT_END
Dbt keyChild;
Dbt record;
record.set_flags(DB_DBT_PARTIAL);
record.set_doff(0);
record.set_dlen(0);
int res = pCursor->pget(&key, &keyChild, &record, DB_SET);
while (res == 0)
{
childrenIds.push_back(RecordID(keyChild));
res = pCursor->pget(&key, &keyChild, &record, DB_NEXT_DUP);
}
if (res != DB_NOTFOUND)
{
throw DbException("Failed to obtain children ids", res);
}
pCursor->close();
pCursor = nullptr;
// delete children
for (const RecordID& childId : childrenIds)
{
del(childId);
}
// delete the record itself
const int err = dbMain_.del(nullptr, &key, /*flags*/0);
if (err && err != DB_NOTFOUND)
{
std::ostringstream ss;
ss << "Failed to delete record id='" << id << '\'';
throw DbException(ss.str().c_str(), err);
}
}示例3: pkey
vector<Identity>
Freeze::IndexI::untypedFindFirst(const Key& bytes, Int firstN) const
{
DeactivateController::Guard
deactivateGuard(_store->evictor()->deactivateController());
Dbt dbKey;
initializeInDbt(bytes, dbKey);
//
// When we have a custom-comparison function, Berkeley DB returns
// the key on-disk (when it finds one). We disable this behavior:
// (ref Oracle SR 5925672.992)
//
dbKey.set_flags(DB_DBT_USERMEM | DB_DBT_PARTIAL);
Key pkey(1024);
Dbt pdbKey;
initializeOutDbt(pkey, pdbKey);
Dbt dbValue;
dbValue.set_flags(DB_DBT_USERMEM | DB_DBT_PARTIAL);
Ice::CommunicatorPtr communicator = _store->communicator();
_store->evictor()->saveNow();
vector<Identity> identities;
try
{
for(;;)
{
Dbc* dbc = 0;
identities.clear();
try
{
//
// Move to the first record
//
_db->cursor(0, &dbc, 0);
u_int32_t flags = DB_SET;
bool found;
do
{
for(;;)
{
try
{
//
// It is critical to set key size to key capacity before the
// get, as a resize that increases the size inserts 0
//
pkey.resize(pkey.capacity());
found = (dbc->pget(&dbKey, &pdbKey, &dbValue, flags) == 0);
if(found)
{
pkey.resize(pdbKey.get_size());
Ice::Identity ident;
ObjectStore::unmarshal(ident, pkey, communicator);
identities.push_back(ident);
flags = DB_NEXT_DUP;
}
break; // for(;;)
}
catch(const DbDeadlockException&)
{
throw;
}
catch(const DbException& dx)
{
handleDbException(dx, pkey, pdbKey, __FILE__, __LINE__);
}
}
}
while((firstN <= 0 || identities.size() < static_cast<size_t>(firstN)) && found);
Dbc* toClose = dbc;
dbc = 0;
toClose->close();
break; // for (;;)
}
catch(const DbDeadlockException&)
{
if(dbc != 0)
{
try
{
dbc->close();
}
catch(const DbDeadlockException&)
{
//
// Ignored
//
}
//.........这里部分代码省略.........
示例4: pkey
vector<Identity>
Freeze::IndexI::untypedFindFirst(const Key& bytes, Int firstN) const
{
DeactivateController::Guard
deactivateGuard(_store->evictor()->deactivateController());
Dbt dbKey;
initializeInDbt(bytes, dbKey);
#if (DB_VERSION_MAJOR <= 4) || (DB_VERSION_MAJOR == 5 && DB_VERSION_MINOR <= 1)
//
// When we have a custom-comparison function, Berkeley DB returns
// the key on-disk (when it finds one). We disable this behavior:
// (ref Oracle SR 5925672.992)
//
dbKey.set_flags(DB_DBT_USERMEM | DB_DBT_PARTIAL);
#else
//
// In DB > 5.1 we can not set DB_DBT_PARTIAL in the key Dbt,
// when using DB_SET, we must resize the Dbt key param to hold enought
// space or Dbc::get fails with DB_BUFFER_SMALL.
//
dbKey.set_flags(DB_DBT_USERMEM);
dbKey.set_ulen(static_cast<u_int32_t>(bytes.size()));
#endif
Key pkey(1024);
Dbt pdbKey;
initializeOutDbt(pkey, pdbKey);
Dbt dbValue;
dbValue.set_flags(DB_DBT_USERMEM | DB_DBT_PARTIAL);
const Ice::CommunicatorPtr& communicator = _store->communicator();
const Ice::EncodingVersion& encoding = _store->encoding();
TransactionIPtr transaction = _store->evictor()->beforeQuery();
DbTxn* tx = transaction == 0 ? 0 : transaction->dbTxn();
vector<Identity> identities;
try
{
for(;;)
{
Dbc* dbc = 0;
identities.clear();
try
{
//
// Move to the first record
//
_db->cursor(tx, &dbc, 0);
u_int32_t flags = DB_SET;
bool found;
do
{
for(;;)
{
try
{
//
// It is critical to set key size to key capacity before the
// get, as a resize that increases the size inserts 0
//
pkey.resize(pkey.capacity());
found = (dbc->pget(&dbKey, &pdbKey, &dbValue, flags) == 0);
if(found)
{
pkey.resize(pdbKey.get_size());
Ice::Identity ident;
ObjectStoreBase::unmarshal(ident, pkey, communicator, encoding);
identities.push_back(ident);
flags = DB_NEXT_DUP;
}
break; // for(;;)
}
catch(const DbDeadlockException&)
{
throw;
}
catch(const DbException& dx)
{
handleDbException(dx, pkey, pdbKey, __FILE__, __LINE__);
}
}
}
while((firstN <= 0 || identities.size() < static_cast<size_t>(firstN)) && found);
Dbc* toClose = dbc;
dbc = 0;
toClose->close();
break; // for (;;)
}
catch(const DbDeadlockException&)
{
//.........这里部分代码省略.........