So what does VLOOKUP do? Like the name implies, it allows you to quickly look up any value that lives somewhere else in your spreadsheet. And then you use INDEX to add the data to the first file.VLOOKUP is one of the most powerful features in Excel, but it's also kind of scary at first glance. This column can be on a different sheet or even in a different file. You make a helper column with MATCH that has the row numbers in the second file in the order they appear in the first file.
So how do you then match up to data tables with the same key column? It's O(N) for an exact match (last param = 0) and O(log(N)) for an aproximate search (last param = -1 or 1) and you only have to do it once for every row and not for every column! You can do the same trick with a double aproximate MATCH as you could do with VLOOKUP to benefit from the speed of binary search and still be guarantueed to be told if there is no exact match. You can store this value in a cell and then use Index for every column you want to match. MATCH determines the row number the matching item is in using a lineair search (the slow one, I know, but because of the way it's implemented it's still faster and uses less memory).
INDEX allows you to take a range and directly reference a value in that range by row and column number. Now consider that if you want to merge multiple columns you have to repeat those VLOOKUPs for every column, so 20 columns is 20x as slow!Īnd now INDEX/MATCH: The power here is that they are two different functions. If you have a large amount of data and you are able to sort them this is faster than a single exact vlookup! Never use FALSE on large sorted datasets!! If you do it in this order at least the second lookup would not be done if an item is not present. If they are equal do the VLOOKUP again and return the value. To speed things up therefore you could sort the data you're searching in and use a double aproximate vlookup in an if statement: The first one you is in the condition and checks against the search value, if they are different then the item is not present, return N/A manually. It does however return an N/A if no exact match is found. The second mode, last parameter FALSE looks for an exact match and does not require sorted data, it does a lineair search and is bog slow. BUT IT DOESNT TELL YOU THIS! The search is O(logN) If the value you look for is not in the table it returns the closest result after the position after where your result should have been. However it also means it looks for an aproximate match. If the last parameter is TRUE (the default if you omit it) it expects a sorted first column and is really fast using a binary search. Reading back all the comments I feel it's best to explain why VLOOKUP is a terrible choice for this particular problem.įirst off it should be noted that VLOOKUP has two wildly different modes of operation. I am 99% sure this is the wrong way to do it but this 1500+ line monstrosity works well and is remarkably quick. This effectively doubles the previous number from 768 to 1536 lines of code.
If a1 = branch 1 then a1 = Branch 1 Street, Streetville, OH Payroll also wants the actual name of the branch so I made another hard coded script that replaces "branch 1" with the actual name and address of the branch.
#How to use vlookup in excel for different sheets code#
So with 3 rows I choose to write that's 256x3 or 768 lines of code instead of a chart lookup table thingy. If a1 = branch 1 and a2 = branch 2 then a3 = 4 (distance between branches)Įach row in excel has at minimum 16x16 or 256 if then statements So in an effort to make it easier to calculate distances between branches I hard coded in excel's visual basic "i believe it's visual basic" the distance between all 16 branches to every other branch on the spreadsheet for the first 3 lines on the excel page. I may go from branch 4 to branch 2 on Monday and then branch 7 to branch 1 to branch 11 on Tuesday. I need better Excel skills like / unlike this not sure judging by comments.Īt work I do alot of traveling between locations pretty much at random.
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