uppercase

STEP 1: Launch Hive

STEP 2: Create or Use a Database
SHOW DATABASES;
CREATE DATABASE IF NOT EXISTS company;
USE company;

Confirm:

SELECT current_database();


step3:
CREATE TABLE employee1 (
  id INT,
  name STRING
)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
TBLPROPERTIES ("skip.header.line.count"="1");

STEP 4:(type exit;)
cd /home/cloudera/
gedit employee1.csv

Paste the data below:

id,name
101,satvik
102,rahul
103,rishi
104,nithish

STEP 5:Reopen Hive
hive
USE company;
LOAD DATA LOCAL INPATH '/home/cloudera/employee1.csv' INTO TABLE employee1;
  
SELECT * FROM employee1;
STEP 6:(type exit;)
gedit CapitalizeUDF.java

import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.io.Text;

public class CapitalizeUDF extends UDF {
    public Text evaluate(Text input) {
        if (input == null) return null;
        String str = input.toString().trim();
        if (str.isEmpty()) return new Text("");
        String result = str.substring(0, 1).toUpperCase() + str.substring(1).toLowerCase();
        return new Text(result);
    }
}

STEP 7: Compile the Java File

In the terminal:

javac -classpath $(hadoop classpath):/usr/lib/hive/lib/* -d . CapitalizeUDF.java

STEP 8: Create a JAR File
jar -cvf CapitalizeUDF.jar CapitalizeUDF.class


Check:
ls
STEP 9: Add JAR to Hive

Open Hive again:

hive
USE company;
ADD JAR /home/cloudera/CapitalizeUDF.jar;


You’ll get:

Added resources: /home/cloudera/CapitalizeUDF.jar

STEP 10: Create a Temporary Function
CREATE TEMPORARY FUNCTION capitalize AS 'CapitalizeUDF';

STEP 11: Use the Function
SELECT id, capitalize(name) AS capitalized_name FROM employee1;