Justin Leet created HIVE-7898:
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Summary: HCatStorer should ignore namespaces generated by Pig
Key: HIVE-7898
URL: https://issues.apache.org/jira/browse/HIVE-7898
Project: Hive
Issue Type: Improvement
Components: HCatalog
Affects Versions: 0.13.1
Reporter: Justin Leet
Assignee: Justin Leet
Priority: Minor
Currently, Pig aliases must exactly match the names of HCat columns for
HCatStorer to be successful. However, several Pig operations prepend a
namespace to the alias in order to differentiate fields (e.g. after a group
with field b, you might have A::b). In this case, even if the fields are in
the right order and the alias without namespace matches, the store will fail
because it tries to match the long form of the alias, despite the namespace
being extraneous information in this case. Note that multiple aliases can be
applied (e.g. A::B::C::d).
A workaround is possible by doing a
FOREACH relation GENERATE field1 AS field1, field2 AS field2, etc.
This quickly becomes tedious and bloated for tables with many fields.
Changing this would normally require care around columns named, for example,
`A::b` as has been introduced in Hive 13. However, a different function call
only validates Pig aliases if they follow the old rules for Hive columns. As
such, a direct change (rather than attempting to match either the
namespace::alias or just alias) maintains compatibility for now.
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