string concatenation not working in pig

Question

I have a table in hcatalog which has 3 string columns. When I try to concatenate string, I am getting the following error:

A = LOAD 'default.temp_table_tower' USING org.apache.hcatalog.pig.HCatLoader() ;
B = LOAD 'default.cdr_data' USING org.apache.hcatalog.pig.HCatLoader();
c = FOREACH A GENERATE CONCAT(mcc,'-',mnc) as newCid;

Could not resolve concat using imports: [, java.lang., org.apache.pig.builtin., org.apache.pig.impl.builtin.]

Could not infer the matching function for org.apache.pig.builtin.CONCAT as multiple or none of them fit. Please use an explicit cast

What might be the root cause of the problem?

What version of Pig do U use? Because CONCAT with more than two arguments is availiable in version 0.13. In previous versions you have to use CONCTAT(CONCAT(mcc,'-'),mnc) — psmith
Reference of CONCAT, which supports more than two arguments and CONCATwhich does not support multiple arguments — vishnu viswanath

Mentya Mentya · Accepted Answer · 2015-07-03T11:58:12

May be it will help for concatenation in pig

data1 contain:

(Maths,abc)
(Maths,def)
(Maths,ef)
(Maths,abc)
(Science,ac)
(Science,bc)
(Chemistry,xc)
(Telugu,xyz)

considering schema as sub:Maths,Maths,Science....etc and name :abc,def ,ef..etc

X = FOREACH data1 GENERATE CONCAT(sub,CONCAT('@',name));

O/P of X is:

(Maths@abc)
(Maths@def)
(Maths@ef)
(Maths@abc)
(Science@ac)
(Science@bc)
(Chemistry@xc)
(Telugu@xyz)

string concatenation not working in pig

1 Answers