How to get the partition column name of a Hive table - hive

Question

I'm developing a unix script where I'll be dealing with Hive tables partitioned by either column A or column B. I'd like to find on what column a table is partition on so that I can do subsequent operations on those partition instances.
Is there any property in Hive which returns the partition column directly?
I'm thinking I'll have to do a show create table and extract the partition name somehow if there isn't any other way possible.

Answer 1

May be not the best, but one more approach is by using describe command
Create table:
create table employee ( id int, name string ) PARTITIONED BY (city string);
Command:
hive -e 'describe formatted employee' | awk '/Partition/ {p=1}; p; /Detailed/ {p=0}'
Output:
# Partition Information
# col_name data_type comment
city string
you can improve it as per your need.
One more option which i dint explore is by querying meta-store repository tables to get the partition column information for a table.

Answer 2

Through scala/java api, we can get to the hive meta store and get the partition column names
org.apache.hadoop.hive.metastore.HiveMetaStoreClient
val conf = new Configuration()
conf.set("hive.metastore.uris","thrift://hdppmgt02.domain.com:9083")
val hiveConf = new HiveConf(conf, classOf[HiveConf])
val metastoreClient = new HiveMetaStoreClient(hiveConf)
metastoreClient.getTable(db, tbl).getPartitionKeys.foreach(x=>println("Keys : "+x))

Answer 3

#use python pyhive:
import hive_client
def get_partition_column(table_name):
#hc=hive connection
hc=hive_client.HiveClient()
cur=hc.query("desc "+table_name)
return cur[len(cur)-1][0]
#################
hive_client.py
from pyhive import hive
default_encoding = 'utf-8'
host_name = 'localhost'
port = 10000
database="xxx"
class HiveClient:
def __init__(self):
self.conn = hive.Connection(host=host_name,port=port,username='hive',database=database)
def query(self, sql):
cursor = self.conn.cursor()
#with self.conn.cursor() as cursor:
cursor.execute(sql)
return cursor.fetchall()
def execute(self,sql):
#with self.conn.cursor() as cursor:
cursor = self.conn.cursor()
cursor.execute(sql)
def close(self):`enter code here`
self.conn.close()

Answer 4

List<String> parts = new ArrayList<>();
try {
List<FieldSchema> partitionKeys = client.getTable(dbName, tableName).getPartitionKeys();
for (FieldSchema partition : partitionKeys) {
parts.add(partition.getName());
}
} catch (Exception e) {
throw new RuntimeException("Fail to get Hive partitions", e);
}