It looks like a silly problem, but I can´t find a way to filter null values from my rows. This is the result when I dump the object geoinfo: DUMP geoinfo; ([longitude#70.95853,latitude#30.9773]) ([longitude#-9.37944507,latitude#38.91780853]) (null) (null) (null) ([longitude#-92.64416,latitude#16.73326]) (null) (null) ([longitude#-9.15199849,latitude#38.71179122]) ([longitude#-9.15210796,latitude#38.71195131]) here is the description DESCRIBE geoinfo; geoinfo: {geoLocation: bytearray} What I'm trying to do is to filter null values like this: geoinfo_no_nulls = FILTER geoinfo BY geoLocation is not null; but the result remains the same. nothing is filtered. I also tried something like this geoinfo_no_nulls = FILTER geoinfo BY geoLocation != 'null'; and I got an error org.apache.pig.backend.executionengine.ExecException: ERROR 1071: Cannot convert a map to a String What am I doing wrong? details, running on ubuntu, hadoop-1.0.3 with pig 0.9.3 pig -version Apache Pig version 0.9.3-SNAPSHOT (rexported) compiled Oct 24 2012, 19:04:03 java version "1.6.0_24" OpenJDK Runtime Environment (IcedTea6 1.11.4) (6b24-1.11.4-1ubuntu0.12.04.1) OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)