Creating an Appended Combined Column to use as a database

[SB98]

Hi all,
I’ve been struggling with this for some time because I need to use formulas to automate the new database column, not VBA or power query. Essentially what I want to do is create a column that combines two other columns but the difference is appended to the bottom. For ease of explanation the combined column is Column E, the database list is column C and the new list is Column A. The combined column E must first list everything in column C and then check list A against list C and then display items in list A that are not already in List C at the end of the combined list column E. Also what would be beneficial is some sort of indicator of which list or column the item is referenced from.
I’m using excel 365.
these ranges in column A and C would not be the same and would be updated periodically .

Thanks!
Example ————————-

A. (New) C. (Database) E. Indicator
Cat. Toes. Toes. C
Dog. Mouse. Mouse C
Mouse. Dog Dog. C
Ham. Eggs. Eggs. C
Eggs. Cheese. Cheese. C
Toast. Toast. C
Cat. A
Ham. A

 

[Fluff]

Doesn't work.
Back soon

 

[Fluff]

Hi & welcome to MrExcel.
How about

+Fluff 1.xlsm
	A	B	C	D	E	F
1
2	Cat		Toes		Toes	C
3	Dog		Mouse		Mouse	C
4	Mouse		Dog		Dog	C
5	Ham		Eggs		Eggs	C
6	Eggs		Cheese		Cheese	C
7			Toast		Toast	C
8					Cat	A
9					Ham	A
Data

Cell Formulas
Range	Formula
E2:F9	E2	=LET(RngA,A2:A6,RngC,C2:C7,f,FILTER(RngA,ISNA(MATCH(RngA,RngC,0))),r,ROWS(RngC),s,SEQUENCE(r+ROWS(f)),IF(s<=r,CHOOSE({1,2},INDEX(RngC,s),"C"),CHOOSE({1,2},INDEX(f,s-r),"A")))
Dynamic array formulas.