[Solved-1 Solution] What exactly does the double colon mean in Pig ?
What is disambiquate operator
- Use the disambiguate operator ( :: ) to identify field names after JOIN, COGROUP, CROSS, or FLATTEN operators.
- In this example, to disambiguate y, use A::y or B::y. In cases where there is no ambiguity, such as z, the :: is not necessary but is still supported.
- When you use DESCRIBE , you can see a lot of double colons in the Pig output, and it's not obvious what they mean.
For example, after grouping and flattening
- At some point you had grouped by observerId and endpoint, renamed the group tuple to 'key', and then reflattened. So, what exactly does the double colon mean ?
- In the question :: is the disambiguate operator and it is use to identify field names after JOIN, COGROUP, CROSS or FLATTEN Operators.
- We can find an example of using disambiguate operator .
- We have two fields observerID and endpoint and they both are identified by the key alias means both observerID and endpoint are referenced in same alias while there could be other "
observerID and endpoint" referenced to other the "
Here is an example:
The above sentence means the observerID and endpoint we see as a part of the key alias not the otherkey alias.