[
https://issues.apache.org/jira/browse/PIG-159?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12595665#action_12595665
]
Santhosh Srinivasan commented on PIG-159:
-----------------------------------------
For backward compatibility in terms of usage, I had to fall back on your
proposal for type specification. Your proposal fits nicely with the existing
syntax. However, there is a restriction that the user has to specify a variable
name.
{code}
--Existing Pig
a = load 'myfile' as (a: (b, c));
--New syntax
a = load 'myfile' as (a: int, b: float, c:chararray);
{code}
The statement in your example with the four options are given below. Note that
for a bag, the type specification is specified within '{' and '}'
{code}
--Option 1
a = load 'myfile' as (x: bag{a: int, b: int, c: int}, y: int, z: bag);
--Option 2
a = load 'myfile' as (x: bag{a: int, b: int, c: int}, y: int, z: bag{});
--Option 3
a = load 'myfile' as (x: bag{a: int, b: int, c: int}, y: int, z: bag{unknown});
--Option 4
a = load 'myfile' as (x: bag{a: int, b: int, c: int}, y: int, z: bag{...});
{code}
> Make changes to the parser to support new types functionality
> -------------------------------------------------------------
>
> Key: PIG-159
> URL: https://issues.apache.org/jira/browse/PIG-159
> Project: Pig
> Issue Type: Sub-task
> Components: impl
> Reporter: Alan Gates
> Assignee: Alan Gates
>
> In order to support the new types functionality described in
> http://wiki.apache.org/pig/PigTypesFunctionalSpec, the parse needs to change
> in the following ways:
> 1) AS needs to support types in addition to aliases. So where previously it
> was legal to say:
> a = load 'myfile' as a, b, c;
> it will now also be legal to say
> a = load 'myfile' as a integer, b float, c chararray;
> 2) Non string constants need to be supported. This includes non-string
> atomic types (integer, long, float, double) and the non-atomic types bags,
> tuples, and maps.
> 3) A cast operator needs to be added so that fields can be explicitly casted.
> 4) Changes to DEFINE, to allow users to declare arguments and return types
> for UDFs
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
