I am not sure wrong with column expression - regexmatcher. I am trying to validate date field format. I have a column with 2 different date format 12/31/2020 2020-01-31 Here is my code if (regexMatcher(column(“column1”), “[^\d]{2}-\d{2}-\d{4}”)) “true”; else “false”; [Screen Shot 2021-08-04 at 7.15.19 PM]

Hi @kamleshpatel , I’m not quite sure what you are wanting the regex to match but since you have the ^ symbol inside the square bracket this acts to negate the \d, so the first part will be trying to match two non-digits. If you were wanting to use ^ to represent “start of line” then it needs to be before the square bracket. It isn’t necessary in this case. The other problem you have is that the \ sign needs to be entered in Column Expression regex as a pair \\ This is because the javascript on which it is based treats the first \ as an escape, so you need to “escape the escape” so that it gets fed correctly as a single \ to the regex parser. I’ve attached a sample with several different regex patterns as an example // returns A if format is nn/nn/nnnn , allowing 1 or 2 digits for month and day if (regexMatcher(column("column1"),"\\d{1,2}/\\d{1,2}/\\d{4}")) {"A"} else // returns B if format is nnnn-nn-nn, allowing 1 or 2 digits for month and day if (regexMatcher(column("column1"),"\\d{4}-\\d{1,2}-\\d{1,2}")) {"B"} else // returns C if format is nn-nn-nnnn, requiring 2 digits for month and day, else D if (regexMatcher(column("column1"),"\\d{2}-\\d{2}-\\d{4}")) {"C"} else {"D"} [image] Note that if this is all you need to do, it is more easily (and probably more efficiently) done with a Rule Engine as follows: $column1$ MATCHES "\d{1,2}/\d{1,2}/\d{4}"=> "A" $column1$ MATCHES "\d{4}-\d{1,2}-\d{1,2}"=> "B" $column1$ MATCHES "\d{2}-\d{2}-\d{4}"=> "C" TRUE => "D" Note that with the Rule Engine, you DON’T escape the \, so that’s something to be wary of. [image] column expression date regex.knwf (8.4 KB)

Column Expression

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ipazin August 6, 2021, 10:32am 6

Not sure about third but there is definitely a case when you need a fourth one

Br,
Ivan

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