Extracting all rows based on a value of cell without VBA - excel

Question

I'm really struggling to find an answer to this as online I've really only found VBA solutions to this problem which isn't what I wish to learn how to do.
THE PROBLEM
BLOOD NAME AGE GENDER
A David 18 Male
B Sarah 22 Female
O Lucy 32 Female
AB Steven 23 Male
O John 11 Male
B Mike 25 Male
AB Paul 24 Male
O Amy 23 Female
B Drake 22 Female
O Linda 11 Female
Very simply from the above dataset I wish to recreate this range but filter for only select BLOOD TYPE O.
MY ATTEMPTS
Started with a VLookup table however that stops at the first occurrence of O. Then tried incorporating IF/THEN/ELSE logic into a MATCH operand trying to locate the row numbers outputting to an array. (not gonna post my failed attempts) I did find a similarish problem online however they solved it via referencing the range manually using ROW(A1), ROW(A2) etc etc wasn't what I after.
Really want to learn how to do this type of iterative selections using Excel formulae only. Even if not solving the problem any direction towards resources where I can learn more about this type problem, would be still appreciated.

Answer 1

This does not use array formulas, but does use a helper column. Assuming data in cols A through D, in E2 enter:
=IF(A2="O",1+MAX($E$1:E1),"")
and copy down:
Each of the O rows is marked with a simple sequential value. This makes it easy for the usual MATCH() / INDEX() methods.
Pick some other cell and enter:
=IFERROR(INDEX(A:A,MATCH(ROWS($1:1),$E:$E,0)),"")
and copy this cell both across and down:

Answer 2

Here is a solution with array formulas. It will calculate extremely slowly, and honestly VBA is a much better solution. You will need to tell excel these are array formulas by hitting "Ctrl + Shift + Enter" after inputting the formulas, this will add the {} around the equation. Finally, drag down the array formulas to see the first "X" results with blood type "O":
First cell formula for "Blood" --> assumes blood is in column A of sheet1
{=IFERROR(INDEX(Sheet1!$A:$D,SMALL(IF(Sheet1!$A:$A="O",ROW(Sheet1!$A:$A)),ROW(1:1)),1,1),"")}
First cell formula for "Name" --> assumes name is in column B of sheet1
{=IFERROR(INDEX(Sheet1!$A:$D,SMALL(IF(Sheet1!$A:$A="O",ROW(Sheet1!$A:$A)),ROW(1:1)),2,1),"")}
First cell formula for "Age" --> assumes age is in column c of sheet1
{=IFERROR(INDEX(Sheet1!$A:$D,SMALL(IF(Sheet1!$A:$A="O",ROW(Sheet1!$A:$A)),ROW(1:1)),3,1),"")}
First cell formula for "Gender" --> assumes gender is in column d of sheet1
{=IFERROR(INDEX(Sheet1!$A:$D,SMALL(IF(Sheet1!$A:$A="O",ROW(Sheet1!$A:$A)),ROW(1:1)),4,1),"")}
Results:
BLOOD NAME AGE GENDER
O Lucy 32 Female
O John 11 Male
O Amy 23 Female
O Linda 11 Female

Answer 3

The following array formula can be put in row 2 (anywhere from column E onward) and copied across 3 columns and down as far as is necessary:
=IFERROR(INDEX(A:A,SMALL(IF(ISNUMBER(SEARCH("O",$A$2:$A$11)),ROW($A$2:$A$11),""),ROW()-1)),"")
This is entered using Ctrl + Shift + Enter and uses a fixed array (A2:A11). If your array is going to change size, you can make the reference to it dynamic by using INDIRECT and COUNTA so that it always encompasses the used range, like so:
=IFERROR(INDEX(A:A,SMALL(IF(ISNUMBER(SEARCH("O",INDIRECT("$A2:$A"&COUNTA(A:A)))),ROW(INDIRECT("$A2:$A"&COUNTA(A:A))),""),ROW()-1)),"")
What is happening:
The SEARCH function is looking for "O"s, then the IF returns the row number if an "O" was found and nothing if no "O" was found.
The SMALL function is looking for the nth instance of the results returned by the SEARCH function, where n = ROW()-1.
The INDEX function returns the nth value from the array A:A, B:B, etc, where n = the row number returned by the SMALL function.
The IFERROR function is not necessary but it makes for a cleaner dataset, all it does is replace the formulas that didn't return anything useful with a blank instead.

Answer 4

Try this standard formula:
= IFERROR( INDEX( A$2:A$11, AGGREGATE( 15, 6,
ROW($A:$A) / ( $A$2:$A$11 = "O" ), ROWS( $A$2:$A2 ) ) ), "" )
or if you want to limit the size of size of column A
= IFERROR( INDEX( A$2:A$11, AGGREGATE( 15, 6,
ROW($A$1:$A$11) / ( $A$2:$A$11 = "O" ), ROWS( $A$2:$A2 ) ) ), "" )
Enter the formula in G2 then copy it to G2:J10