Status Operators::INL(const string& result, // Name of the output relation
const int projCnt, // Number of attributes in the projection
const AttrDesc attrDescArray[], // The projection list (as AttrDesc)
const AttrDesc& attrDesc1, // The left attribute in the join predicate
const Operator op, // Predicate operator
const AttrDesc& attrDesc2, // The right attribute in the join predicate (INDEXED)
const int reclen) // Length of a tuple in the output relation
{
cout << "Algorithm: Indexed NL Join" << endl;
AttrDesc* r;
int num;
Status status = attrCat->getRelInfo(result, num, r);
if(status != OK) return status;
// Load heap 1
HeapFileScan heap1 = HeapFileScan(attrDesc1.relName, status);
if (status != OK) return status;
// Load heap 2
HeapFileScan heap2 = HeapFileScan(attrDesc2.relName, status);
if (status != OK) return status;
// Open output heap
HeapFile heapOut = HeapFile(result, status);
if (status != OK) return status;
// Get size of output record
int size = 0;
for (int x = 0; x < projCnt; x++)
{
size += attrDescArray[x].attrLen;
}
// Create/find the index (checked to ensure indexed before entering this fn)
Index index = Index(attrDesc2.relName, attrDesc2.attrOffset, attrDesc2.attrLen, (Datatype)attrDesc2.attrType, 1, status);
if (status != OK) return status;
//Start Join
RID rid, rid1, rid2;
Record record1, record2;
while(heap1.scanNext(rid1, record1) == OK)
{
char* data1 = (char *) record1.data;
// Update Heapfile Scan for Next Loop
heap2 = HeapFileScan(attrDesc2.relName, status);
if(status != OK) return status;
// Restart the Index Scan for Next Loop
status = index.startScan((char *) record1.data + attrDesc1.attrOffset);
if(status != OK) return status;
while(index.scanNext(rid2) == OK)
{
status = heap2.getRandomRecord(rid2, record2);
if(status != OK) return status;
char* data2 = (char *) record2.data;
// Compare the values stored in both records
int valueDif = matchRec(record1, record2, attrDesc1, attrDesc2);
if(!valueDif)
{
// Add to output heap
Record record;
record.data = malloc(size);
record.length = size;
//Need to check through attrDescArray to find outside heap attrDescs
for(int i = 0; i < projCnt; i++)
{
AttrDesc tempAttr = attrDescArray[i];
//Insert from attrDesc1
if( !strcmp(attrDesc1.relName, tempAttr.relName))
{
memcpy(((char*) record.data) + r[i].attrOffset, data1 + tempAttr.attrOffset, tempAttr.attrLen);
}
else
{
memcpy(((char*) record.data) + r[i].attrOffset, data2 + tempAttr.attrOffset, tempAttr.attrLen);
}
}
// Now insert the record into the output
status = heapOut.insertRecord(record, rid);
if(status != OK) return status;
}
}
// End the scan and restart it again next iteration
status = index.endScan();
if(status != OK) return status;
}
status = heap1.endScan();
if(status != OK) return status;
return OK;
}
