From webinar on December 3, 2019
New users of ClickHouse love the speed but may run into a few surprises when designing applications. Column storage turns classic SQL design precepts on their heads. This talk shares our favorite tricks for building great applications. We'll talk about fact tables and dimensions, materialized views, codecs, arrays, and skip indexes, to name a few of our favorites. We'll show examples of each and also reserve time to handle questions. Join us to take your next step to ClickHouse guruhood!
Speaker Bio:
Robert Hodges is CEO of Altinity, which offers enterprise support for ClickHouse. He has over three decades of experience in data management spanning 20 different DBMS types. ClickHouse is his current favorite. ;)
ClickHouse tips and tricks. Webinar slides. By Robert Hodges, Altinity CEO
1.
2. Introduction to Presenter
www.altinity.com
Leading software and services
provider for ClickHouse
Major committer and community
sponsor in US and Western Europe
Robert Hodges - Altinity CEO
30+ years on DBMS plus
virtualization and security.
ClickHouse is DBMS #20
3. Introduction to ClickHouse
Understands SQL
Runs on bare metal to cloud
Shared nothing architecture
Uses column storage
Parallel and vectorized execution
Scales to many petabytes
Is Open source (Apache 2.0)
a b c d
a b c d
a b c d
a b c d
And it’s really fast!
5. Enabling server logs in clickhouse-client
clickhouse-client --send_logs_level=trace
(OR)
my-host :) SET send_logs_level = 'trace'
my-host :) SELECT 1
my-host :) SET send_logs_level = 'none'
Ask for logs at start
of the session
Ask for logs during
the session
6. It works in Python too!
# Configure logging.
import logging
logging.basicConfig(level=logging.DEBUG)
# Execute a query using log settings.
from clickhouse_driver import Client
client = Client('localhost')
settings = {'send_logs_level': 'trace'}
result = client.execute('SELECT 1', settings=settings)
print("RESULT: {0}".format(result))
Sends logs
to stdout
48. Thank you!
Special Offer:
Contact us for a
1-hour consultation!
Presenter:
rhodges@altinity.com
Visit us at:
https://www.altinity.com
Free Consultation:
https://blog.altinity.com/offer