Hi I have a avro schema with array of struct and I am able to save data as avro. but while retrieving the data from
array<struct<string, string>>
I am unable to get in rows. All the data I am getting in single row.
here is the table definition
CREATE EXTERNAL TABLE meterevents ROW FORMAT SERDE org.apache.hadoop.hive.serde2.avro.AvroSerDe' STORED as INPUTFORMAT org.apache.hadoop.hive.ql.io.avro.AvroContainerInputFormat' OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.avro.AvroContainerOutputFormat' LOCATION '/......' TBLPROPERTIES ('avro.schema.url'='/..../schema.avsc');
hive table structure
nametype struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>> from deserializer
names struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>> from deserializer
enddeviceeventdetails struct<enddeviceeventdetailsname:string,enddeviceeventdetailsvalue:string> from deserializer
enddeviceevent struct<mrid:string,createddatetime:string,issuerid:string,issuertrackingid:string,reason:string,severity:string,userid:string,asset:struct<assetmrid:string,assetnames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>>,enddeviceeventdetails:array<struct<enddeviceeventdetailsname:string,enddeviceeventdetailsvalue:string>>,enddeviceeventtype:string,enddeviceeventnames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>,status:struct<statusdatetime:string,statusreason:string,statusremark:string,statusvalue:string>,usagepoint:struct<usagepointmrid:string,usagepointnames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>>> from deserializer
enddeviceeventtype struct<enddeviceeventtypemrid:string,enddeviceeventtypedomain:string,enddeviceeventtypeeventoraction:string,enddeviceeventtypesubdomain:string,type:string,enddeviceeventtypenames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>> from deserializer
header struct<noun:string,context:string,verb:string,value:string,source:string,timestamp:string,correlationid:string,name:string,messageid:string,property:struct<propertyname:array<string>,propertyvalue:array<string>>> from deserializer
payload struct<enddeviceevents:array<struct<mrid:string,createddatetime:string,issuerid:string,issuertrackingid:string,reason:string,severity:string,userid:string,asset:struct<assetmrid:string,assetnames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>>,enddeviceeventdetails:array<struct<enddeviceeventdetailsname:string,enddeviceeventdetailsvalue:string>>,enddeviceeventtype:string,enddeviceeventnames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>,status:struct<statusdatetime:string,statusreason:string,statusremark:string,statusvalue:string>,usagepoint:struct<usagepointmrid:string,usagepointnames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>>>>,enddeviceeventtype:array<struct<enddeviceeventtypemrid:string,enddeviceeventtypedomain:string,enddeviceeventtypeeventoraction:string,enddeviceeventtypesubdomain:string,type:string,enddeviceeventtypenames:array<struct<name:string,nametype:struct<nametypedescription:string,nametypename:string,nametypeauthority:struct<nametypeauthorityname:string,nametypeauthoritydescription:string>>>>>>>
I am using "LATERAL VIEW explode" option in my query
select eddetails.enddeviceeventdetailsname, eddetails.enddeviceeventdetailsvalue
FROM meterevents_tmp
LATERAL VIEW explode(payload.enddeviceevents.enddeviceeventdetails) ed AS eddetails
limit 1;
but still I am getting the data in single row.
enddeviceeventdetailsname enddeviceeventdetailsvalue
["EventSequenceNumber","EventSequenceNumber","EventSequenceNumber","EventSequenceNumber"] ["683","684","685","686"
I would like to have this data as
enddeviceeventdetailsname enddeviceeventdetailsvalue
EventSequenceNumber 683
EventSequenceNumber 684
EventSequenceNumber 685
EventSequenceNumber 686
I have read the other question on the stackoverflow : Exploding Array of Struct using HiveQL
But unable to get the expected output. Since in that post its hive external table and not a serde where I am unable to specify "MAP KEYS TERMINATED BY" and "COLLECTION ITEMS TERMINATED BY"
any help is much appreciated.
Thanks
I was able to resolve this ---
I was not able to get the output in rows because the
array<struct<string,string>>
was part of parent array
array<struct<array<struct<string, string>>>
I updated my query and used the nested explod
select eddetails.enddeviceeventdetailsname, eddetails.enddeviceeventdetailsvalue from (select ede.enddeviceeventdetails FROM meterevents_tmp LATERAL VIEW explode(payload.enddeviceevents) e AS ede) t LATERAL VIEW explode(t.enddeviceeventdetails) ed AS eddetails limit 10;
I got the desired output -
enddeviceeventdetailsname enddeviceeventdetailsvalue
EventSequenceNumber 683
EventSequenceNumber 684
EventSequenceNumber 685
EventSequenceNumber 686