char* BANDB::read(int transID, int key) {
int pageIndex = bm->findKey(key);
if (pageIndex == -1) { return ""; }
Record* rec = bm->locateRecord(pageIndex, key);
return rec->readData();
}
bool BANDB::remove(int transID, int key) {
int pageIndex = bm->findKey(key);
if (pageIndex == -1) { return false; }
int pageNum = bm->getNumAtIndex(pageIndex);
Record* oldRecP = bm->locateRecord(pageIndex, key);
Record oldRec = *oldRecP;
char* oldData = (char*) &oldRec;
char empty[16] = {};
for (int i = 0; i < 16; i++) { empty[i] = 0; }
bool result = bm->removeRecord(pageIndex, key);
lm->writeWriteRecord(transID, pageNum, oldData, empty);
return result;
}
bool BANDB::write(int transID, int key, char* data) {
int pageIndex = bm->findKey(key);
if (pageIndex == -1) { pageIndex = bm->findKey(0); }
if (pageIndex == -1) { return false; }
int pageNum = bm->getNumAtIndex(pageIndex);
Record* oldRecP = bm->locateRecord(pageIndex, key);
Record oldRec = *oldRecP;
char* oldData = (char*) &oldRec;
Record newRec = Record(key, data);
char* newData = (char*) &newRec;
bool result = bm->insertRecord(pageIndex, key, data);
lm->writeWriteRecord(transID, pageNum, oldData, newData);
return result;
}
