topic Re: How to use hash in talend in Talend Studio

How to use hash in talend

dwhdeveloper — Mon, 23 Jan 2017 17:35:30 GMT

I am inserting data in a table from another.
I would like to add a column hash which has hash of all the columns of each row being inserted.
How would I do that in Talend?

Re: How to use hash in talend

Anonymous — Tue, 24 Jan 2017 08:17:30 GMT

Can you please explain better what do you want to produce?

Re: How to use hash in talend

TRF — Tue, 24 Jan 2017 08:55:06 GMT

Hi,
1st, define a routine for conversion (here, mine is called GetHashCode and convert to MD5):

package routines;
import java.security.*;
public class GetHashCode {
	public static String getMD5(String strCode) {
		java.security.MessageDigest msg;
		String digest1 = "";
		try {
			msg = java.security.MessageDigest.getInstance("MD5");
			msg.update(strCode.getBytes(), 0, strCode.length());
			digest1 = new java.math.BigInteger(1, msg.digest()).toString(32);
		}
		catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return digest1.toUpperCase();
	}
}

In tMap, add the desired field to your schema, then call the routine passing the input fields concateneted, and push the result to the new field (here is an example):

GetHashCode.getMD5(row1.col1 + row1.col2 + row1.col3)

Hope this helps,
TRF

Re: How to use hash in talend

offcourse2 — Mon, 09 Sep 2019 15:32:38 GMT

I used this code and it worked perfectly. Is it possible to fix the number of character of the hash?

Currently it ranges between 23 and 26 characters, and I'd like to fix that, ensuring I have no duplicates.

Thanks