/**
* Delete the specified tuple from the page; the tuple should be updated to reflect that it is no
* longer stored on any page.
*
* @throws DbException if this tuple is not on this page, or tuple slot is already empty.
* @param t The tuple to delete
*/
public void deleteTuple(Tuple t) throws DbException {
// some code goes here
// not necessary for lab1
RecordId targetrid = t.getRecordId();
int tslotnum = targetrid.tupleno();
if (!targetrid.getPageId().equals(pid) || !isSlotUsed(tslotnum)) {
throw new DbException("Either wrong page number or requested tuple didn't exist");
}
markSlotUsed(tslotnum, false);
tuples[tslotnum] = null;
}
// see DbFile.java for javadocs
public Page deleteTuple(TransactionId tid, Tuple t)
throws DbException, TransactionAbortedException {
// some code goes here
BufferPool bp = Database.getBufferPool();
RecordId rid = t.getRecordId();
if (rid == null) {
throw new DbException("Tuple is not a member of this file");
}
HeapPage p = (HeapPage) bp.getPage(tid, rid.getPageId(), Permissions.READ_WRITE);
p.deleteTuple(t);
return p;
}