15-415 Fall 2009 B+ Tree Recitation Leman Akoglu 9/30/2009

Schedule Overview of the provided B+ tree package Assignment 5 – the what’s Assignment 5 – the how’s 11/13/2018 B+ Tree Recitation

B+ Tree Package – Compile&Run make main  compiles the source code ./main This starts you with an “empty” B+ tree 11/13/2018 B+ Tree Recitation

B+ Tree Package – Existing Func.s "P” to scan and print all the keys in the tree "i" to insert "p" to print a B+ tree page (p 1 prints the root) "s" to search and print the key "S" to search and print the key as well as its posting list "T" to print the B+ tree in in-order format "x" to exit 11/13/2018 B+ Tree Recitation

B+ Tree Package – Main SRC files main.c parses the input scanTree.c scans the keys in the tree How leaf pages are accessed insert.c inserts a given key Looks for the insert position for a given key search.c to search and print the key How to traverse child nodes strdist.c returns distance between two keys 11/13/2018 B+ Tree Recitation

B+ Tree Package – Preloaded make loaddb compiles the source code and inserts keys from several example text files ./main starts you with a B+ tree to play with 11/13/2018 B+ Tree Recitation

Assignment 5 – the what’s WHAT TO IMPLEMENT:  2 new functions Medium difficulty: range queries R <key1> <key2> print keys in-between r <key1> <key2> print count of keys in-between More difficult: all-pairs queries A < ε > print pairs of keys within ε distance a < ε > print count of pairs of keys within ε Show the given code and point to functions Say that they print Please implement me right now 11/13/2018 B+ Tree Recitation

Assignment 5 – the how’s HOW TO START: All source files are in SRC Implement: 1) R  keysInRange.c 2) r  countKeysInRange.c 3) A  allPairsWithin.c 4) a  countAllPairsWithin.c Note: If you include .c files of your own, do not forget to update SRC/makefile Show the makefile in SRC and how the .c files are included there 11/13/2018 B+ Tree Recitation

Assignment 5 – the how’s HOW TO TEST: Run ‘make hw5’ no errors/warnings diff’s should be empty Sample test files in Tests generate test files for yourself if necessary Note: We will use other tests for grading Show the sample tests and their outputs Show what make hw does 11/13/2018 B+ Tree Recitation

Reminders Start EARLY! Your implementation should be correct AND efficient. No hard-copy this time. Tar your source code and send it to lakoglu@cs.cmu.edu with subject ‘submission homework 5’. Talk about efficiency 11/13/2018 B+ Tree Recitation

Questions? Provided B+ tree package Assignment 5 – the what’s Assignment 5 – the how’s 11/13/2018 B+ Tree Recitation