Read CSV file and want to find duplicate value

Could you elaborate more on what you are trying to do? Are you looking for duplicates on "No" and/or "col1" and/or "col2"? What are you expecting in error1/2/3? What does your current expression rule look like, and what have you tried for finding the duplicate values that is giving you difficulty?

Dan Lluhi 

At first i want to read csv file and then check csv file data. I'm looking for duplicate value on [No] column.

if there are duplicate value on [No] column. i want to add error msg and sent it back csv file with error message.

If there  are no duplicate value register to DB. 

Please find the below code. Made a sample code for your understanding. More efficient and simpler code can be created.

a!localVariables(
  local!doc: ri!doc,
  local!data: readexcelsheetpaging(
    excelDocument: ri!doc,
    sheetNumber: 0,
    pagingInfo: a!pagingInfo(startIndex: 2, batchSize: 5000)
  ).data.values,
  local!formatData: a!forEach(
    items: local!data,
    expression: if(
      a!isNullOrEmpty(fv!item[2]),
      {},
      a!map(
        name: fv!item[2],
        gender: fv!item[3],
        department: fv!item[4],
        tech: fv!item[5]
  )
  )
  ),
  local!duplicateCheck: a!forEach(
    items: local!formatData,
    expression: a!update(
      data: fv!item,
      index: "error",
      value: if(
        length(
          wherecontains(
            fv!item.name,
            local!formatData.name
          )
        )>1,
        "Duplicate Values Found",
        ""
      )
    )
  ),
  local!duplicateCheck
)

Konduru Chaitanya 

Really helpful for me. I understand and work for me!!!

Thank you so much for your help

Konduru Chaitanya 

I have another question, I would like to create a CSV file with the current results.

 How can i get it more efficiently.

If the answer works please do verify the answers which helped you.

yes.I made it

Where are you planning to use this output error exactly would be my first question. That would help get a better answer.

Konduru Chaitanya 

If my result have a error msg i need to create a csv file with error msg  .

This error msg csv file will show in interface  and then user can download the link of that csv file .

If  my result have not  error msg i will register that csv file result  to DB.

From what I understand, you are trying to create a validation.

if(
   contains(
     local!duplicateCheck.error,
     "Duplicate Values Found"
   ),
   "This file contains one or more duplicate values.",
   ""
 )

In the code provided before replace the local variable used for getting the output with this.