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Drill >> mail # dev >> Trivial project?


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Re: Trivial project?
Hi Julian,

Have you tried just putting in the field name you're looking for?

If you want all fields, probably should just get rid of the project.

Tim
On Tue, Mar 26, 2013 at 1:59 PM, Julian Hyde <[EMAIL PROTECTED]> wrote:

> I would like to generate a trivial project operator that returns the
> entire input record. What expression should I use?
>
> When implementing "select * from donuts", here is the logical plan I am
> currently generating:
>
> {
>   "head" : {
>     "type" : "apache_drill_logical_plan",
>     "version" : 1,
>     "generator" : {
>       "type" : "manual",
>       "info" : "na"
>     }
>   },
>   "storage" : [ {
>     "type" : "classpath",
>     "name" : "donuts-json"
>   }, {
>     "type" : "queue",
>     "name" : "queue"
>   } ],
>   "query" : [ {
>     "op" : "scan",
>     "@id" : 1,
>     "memo" : "initial_scan",
>     "storageengine" : "donuts-json",
>     "selection" : {
>       "path" : "/donuts.json",
>       "type" : "JSON"
>     },
>     "ref" : "donuts"
>   }, {
>     "op" : "project",
>     "@id" : 2,
>     "input" : 1,
>     "exprs" : [ {
>       "ref" : "output._MAP",
>       "expr" : null
>     } ]
>   }, {
>     "op" : "store",
>     "@id" : 3,
>     "memo" : "output sink",
>     "input" : 2,
>     "target" : {
>       "number" : 0
>     },
>     "partition" : null,
>     "storageEngine" : "queue"
>   } ]
> }
>
> The
>
>       "expr" : null
>
> causes the reference implementation to barf (not surprisingly). What
> should I put in place of "null"?
>
> Julian