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Hive, mail # user - Adding comment to a table for columns


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Re: Adding comment to a table for columns
bejoy_ks@... 2013-02-21, 11:20
Hi Gupta

You can the describe output in a formatted way using

DESCRIBE FORMATTED <table name>;

Regards
Bejoy KS

Sent from remote device, Please excuse typos

-----Original Message-----
From: Chunky Gupta <[EMAIL PROTECTED]>
Date: Thu, 21 Feb 2013 16:46:30
To: <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Subject: Adding comment to a table for columns

Hi,

I am using this syntax to add comments for all columns :-

CREATE EXTERNAL TABLE test ( c STRING COMMENT 'Common  class', time STRING
COMMENT 'Common  time', url STRING COMMENT 'Site URL' ) PARTITIONED BY (dt
STRING ) LOCATION 's3://BucketName/'

Output of Describe Extended table is like :- (Output is just an example
copied from internet)

hive> DESCRIBE EXTENDED table_name;

Detailed Table Information Table(tableName:table_name, dbName:benchmarking,
owner:root, createTime:1309480053, lastAccessTime:0, retention:0,
sd:StorageDescriptor(cols:[FieldSchema(name:session_key, type:string,
comment:null), FieldSchema(name:remote_address, type:string, comment:null),
FieldSchema(name:canister_lssn, type:string, comment:null),
FieldSchema(name:canister_session_id, type:bigint, comment:null),
FieldSchema(name:tltsid, type:string, comment:null),
FieldSchema(name:tltuid, type:string, comment:null),
FieldSchema(name:tltvid, type:string, comment:null),
FieldSchema(name:canister_server, type:string, comment:null),
FieldSchema(name:session_timestamp, type:string, comment:null),
FieldSchema(name:session_duration, type:string, comment:null),
FieldSchema(name:hit_count, type:bigint, comment:null),
FieldSchema(name:http_user_agent, type:string, comment:null),
FieldSchema(name:extractid, type:bigint, comment:null),
FieldSchema(name:site_link, type:string, comment:null),
FieldSchema(name:dt, type:string, comment:null), FieldSchema(name:hour,
type:int, comment:null)],
location:hdfs://hadoop2/user/hive/warehouse/benchmarking.db/table_name,
inputFormat:org.apache.hadoop.mapred.SequenceFileInputFormat,
outputFormat:org.apache.hadoop.hive.ql.io.HiveSequenceFileOutputFormat,
compressed:false, numBuckets:-1, serdeInfo:SerDeInfo(name:null,
serializationLib:org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe)

Is there any way of getting this detailed comments and column name in
readable format, just like the output of "Describe table_name" ?.
Thanks,

Chunky.