Kalai
Kalai

Reputation: 319

Field count in PIG

Is there any way to find the number of Fields or columns available in a relation?

For example:

a = load 'input' using PigStorage(',') as (a1,a2,a3);

b = load 'input2' using PigStorage(',') as (b1,b2,b3);

C = join a by a1, b by b1;

Now there will be six columns in the result 'c'. Is there any way to check the count of columns in the result by code.

Thanks,

Kalai

Upvotes: 1

Views: 740

Answers (1)

Yashodhan K
Yashodhan K

Reputation: 179

PIG does not provide any intentional way of counting columns but one of the way to use the count of fields in pig is by 1st -storing the file and then counting the no of delimiters in the file.

Example:- (Delimiter used is "|")

%declare COUNT hadoop fs -cat //trihadn01/user/ykale/warranty_recs | head -1| tr '|' '\n'|wc -l;

and then use this variable - COUNT where ever required in pig.

Note- Please do not miss the '`' symbol at the end of the statement and after the variable name (count)

Upvotes: 2

Related Questions