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How to check whether a column exist in a table?

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Alon Rozen
Alon Rozen on 24 Nov 2016
Answered: Sean Lynch on 5 Sep 2021
Hi all,
I search for this question in the web and found the following solution: Suppose I have a table named 'My_Table' and want to check if it contains a column (field) named 'My_Column'. The code:
Exist_Column = strmatch('My_Column',My_Table.Properties.VariableNames)
should result in logical that answer the question. I checked it and it works. However, the Matlab editor commented that 'strmatch' is not a recommended function to use because it is about to be removed in future version and suggest instead the use of either 'strncmp' or 'validatestring'. Problem is that both do not return a logical and more steps are required to get the answer.
So, my question is: what is the simplest recommended way to determine if a certain column name exist in a table?
Thanks,
Alon
  1 Comment
Carlos Aguilar
Carlos Aguilar on 31 Dec 2017
Just came across to this question. An anonymous function will also do the job (and will be reusable within the scope):
isTableCol = @(t, thisCol) ismember(thisCol, t.Properties.VariableNames);

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Accepted Answer

KSSV
KSSV on 24 Nov 2016
Exist_Column = strcmp('My_Column',My_Table.Properties.VariableNames)
val = Exist_Column(Exist_Column==1) ;
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More Answers (2)

jkr
jkr on 14 May 2019
sum(ismember(mx.Properties.VariableNames,'NameYouWantToCheck'))
returns 1 if found, 0 if not
  1 Comment
AusPollen
AusPollen on 23 May 2021
Nice! although you don't need to sum if you switch the ismember arguments, ie. use ismember('My_Column',My_Table.Properties.VariableNames)

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Sean Lynch
Sean Lynch on 5 Sep 2021
I used "any", but agree "ismember" is even better
exists = any(strcmp('Column-Name', My_Table.Properties.VariableNames))

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