Database Reference
In-Depth Information
# for all reviews of Dune, count them up and sum the rankings
for
for
m
iin
mcur
:
count
+=
1
sum
+=
m
[
'rating'
]
client
.
close
()
rank
=
float
(
sum
)
/
float
(
count
)
print
print
(
'Dune
%s
\\n'
%
rank
)
Hive
License
Apache License, Version 2.0
Activity
High
Purpose
Data Interaction
Official Page
http://hive.apache.org
Integration
Fully Integrated
At first, all access to data in your Hadoop cluster came through MapReduce jobs written in
Java. This worked fine during Hadoop's infancy when all Hadoop users had a stable of Java-
savvy coders. However, as Hadoop emerged into the broader world, many wanted to adopt
Hadoop but had stables of SQL coders for whom writing MapReduce would be a steep learn-
ing curve. Enter Hive. The goal of Hive is to allow SQL access to data in the HDFS. The
Apache Hive data-warehouse software facilitates querying and managing large datasets
residing in HDFS. Hive defines a simple SQL-like query language, called HQL, that enables
users familiar with SQL to query the data. Queries written in HQL are converted into
MapReduce code by Hive and executed by Hadoop. But beware! HQL is not full ANSI-
standard SQL. While the basics are covered, some features are missing. Here's a partial list
as of early 2015:
