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What is UCFIRST()?
- This function accepts a string, converts the first letter of it into uppercase, and returns the result.
- ucfirst is a function which exists natively in PHP and other languages. It is used to capitalize the first character of a string.
Syntax:
Here is the syntax of the function UCFIRST() function.
grunt> UCFIRST(expression)
Example:
Assume that there is a file named wikitechy_emp.txt in the HDFS directory /pig_data/as shown below. This file contains the employee details such as id, name, age, and city.
wikitechy_emp.txt
001,Aadav,32,Tokyo
002,Aadhi,33,Kolkata
003,Charu,23, London
004,Daya,35,London
005, Hansa,22,Bhuwaneshwar
006, Hena,21,Chennai
007,Robert,24, Bhuwaneshwar
008,Kali,20,Kolkata
009,Leena,22, Chennai
010,Mahi,22, newyork
011,Priya,23, Tokyo
012,Rahul,20, newyork
And, we have loaded this file into Pig with a relation named wikitechy_emp_data as shown below.
grunt> wikitechy_emp_data = LOAD 'hdfs://localhost:9000/pig_data/wikitechy_emp.txt' USING PigStorage(',')
as (id:int, name:chararray, age:int, city:chararray);
Following is an example of the UCFIRST() function. In this example, we are trying to convert the first letters of the names of the cities, to which the employees belong to, to uppercase.
grunt> ucfirst_data = FOREACH wikitechy_emp_data GENERATE (id,city), UCFIRST(city);
- The result of the statement will be stored in the relation named ucfirst_data. Verify the content of the relation ucfirst_data, using the Dump operator as shown below.
- In our example, the first letter of the name of the city “tokyo” is in lowercase. After applying UCFIRST() function, it turns into “TOKYO”
grunt>Dump ucfirst_data;
((1,Tokyo),Tokyo)
((2,Kolkata),Kolkata)
((3,London),London)
((4,London),London)
((5,Bhuwaneshwar),Bhuwaneshwar)
((6,Chennai),Chennai)
((7,Bhuwaneshwar),Bhuwaneshwar)
((8,Kolkata),Kolkata)
((9,Chennai),Chennai)
((10,newyork),Newyork)
((11,Tokyo),Tokyo)
((12,newyork),Newyork)