156 Large Scale and Big Data
• Map: Collection of data items where each item can be looked up by an
associated key.
'name' 'John'
'knows'
('Sarah')
('Bob')
→
Operators: A Pig Latin program consists of a sequence of instructions where
each instruction performs a single data transformation. We shortly introduce those
Pig Latin operators that we used for our translation. The interested reader can nd a
more detailed description of Pig Latin in [16].
• LOAD deserializes the input data and maps it to the data model of Pig
Latin. The user can implement a User Dened Function (UDF) that denes
how to map an input tuple to a Pig Latin tuple as shown in the following
example. The result of LOAD is a bag of tuples.
people = LOAD 'input' USING ...