cancel
Showing results for 
Search instead for 
Did you mean: 
Data Engineering
Join discussions on data engineering best practices, architectures, and optimization strategies within the Databricks Community. Exchange insights and solutions with fellow data engineers.
cancel
Showing results for 
Search instead for 
Did you mean: 

Forum Posts

brickster_2018
by Databricks Employee
  • 20015 Views
  • 1 replies
  • 2 kudos

Resolved! How do I change the log level in Databricks?

How can I change the log level of the Spark Driver and executor process?

  • 20015 Views
  • 1 replies
  • 2 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 2 kudos

Change the log level of Driver:%scala   spark.sparkContext.setLogLevel("DEBUG")   spark.sparkContext.setLogLevel("INFO")Change the log level of a particular package in Driver logs:%scala   org.apache.log4j.Logger.getLogger("shaded.databricks.v201809...

  • 2 kudos
brickster_2018
by Databricks Employee
  • 6874 Views
  • 1 replies
  • 1 kudos
  • 6874 Views
  • 1 replies
  • 1 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 1 kudos

Disclaimer: This code snippet uses an internal API. It's not recommended to use internal API's in your application as they are subject to change or discontinuity. %python import requests API_URL = dbutils.notebook.entry_point.getDbutils().notebook(...

  • 1 kudos
brickster_2018
by Databricks Employee
  • 3789 Views
  • 1 replies
  • 0 kudos

Resolved! Why do I see my job marked as failed on the Databricks Jobs UI, even though it completed the operations in the application

I have a jar job running migrated from EMR to Databricks. The job runs as expected and completes all the operations in the application. However the job run is marked as failed on the Databricks Jobs UI.

  • 3789 Views
  • 1 replies
  • 0 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 0 kudos

Usage of spark.stop(), sc.stop() , System.exit() in your application can cause this behavior. Databricks manages the context shutdown on its own. Forcefully closing it can cause this abrupt behavior.

  • 0 kudos
brickster_2018
by Databricks Employee
  • 1907 Views
  • 1 replies
  • 2 kudos

Few things you should not do in Databricks!

Few things you should not do in Databricks!

  • 1907 Views
  • 1 replies
  • 2 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 2 kudos

Compared to OSS Spark, these are few things the users don't have to worry about when running the same job on Databricks. Memory management: Databricks use an internal formula to allocate the Driver and executor heap based on the size of the instance....

  • 2 kudos
brickster_2018
by Databricks Employee
  • 4047 Views
  • 1 replies
  • 0 kudos
  • 4047 Views
  • 1 replies
  • 0 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 0 kudos

Although not a hard limit, it's recommended to keep the number of cells in the notebook less than 100 for better UI experience as well as code readability. Having a really large block of code in a cell defeats the purpose of notebook execution and al...

  • 0 kudos
brickster_2018
by Databricks Employee
  • 24244 Views
  • 1 replies
  • 0 kudos
  • 24244 Views
  • 1 replies
  • 0 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 0 kudos

Yes, it's possible to download files from DBFS. To download the filesFiles stored in /FileStore are accessible in your web browser at https://<databricks-instance-name>.cloud.databricks.com/files/. For example, the file you stored in /FileStore/my-da...

  • 0 kudos
User16783853501
by Databricks Employee
  • 2378 Views
  • 2 replies
  • 0 kudos

What is the best way to convert a very large parquet table to delta ? possibly without downtime!

What is the best way to convert a very large parquet table to delta ? possibly without downtime! 

  • 2378 Views
  • 2 replies
  • 0 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 0 kudos

I vouch for Sajith's answer. The main advantage with "CONVERT TO DELTA" is that operations are metadata centric which means we are not reading the full data for the conversion. For any other file format conversion, it's necessary to read the data com...

  • 0 kudos
1 More Replies
brickster_2018
by Databricks Employee
  • 2497 Views
  • 2 replies
  • 0 kudos

Why should I move to Auto-loader?

I have a streaming workload using the S3-SQS Connector. The streaming job is running fine within the SLA. Should I migrate my job to use the auto-loader? If Yes, what are the benefits? who should migrate and who should not?

  • 2497 Views
  • 2 replies
  • 0 kudos
Latest Reply
brickster_2018
Databricks Employee
  • 0 kudos

That makes sense @Anand Ladda​ ! One major improvement that will have a direct impact on the performance is the architectural difference. S3-SQS uses an internal implementation of the Delta table to store the checkpoint details about the source files...

  • 0 kudos
1 More Replies
aladda
by Databricks Employee
  • 3993 Views
  • 1 replies
  • 0 kudos
  • 3993 Views
  • 1 replies
  • 0 kudos
Latest Reply
aladda
Databricks Employee
  • 0 kudos

Stats collected on a Delta column are either using for Partitioning Pruning, Data Skipping. See here - https://docs.databricks.com/delta/optimizations/file-mgmt.html#delta-data-skipping for detailsIn additional stats are also used for Metadata only q...

  • 0 kudos
User16783853501
by Databricks Employee
  • 2363 Views
  • 2 replies
  • 0 kudos

Delta Optimistic Transactions Resolution and Exceptions

What is the best way to deal with concurrent exceptions in Delta when you have multiple writers on the same delta table ?

  • 2363 Views
  • 2 replies
  • 0 kudos
Latest Reply
sajith_appukutt
Databricks Employee
  • 0 kudos

While you can try-catch-retry , it would be expensive to retry as the underlying table snapshot would have changed. So the best approach is to avoid conflicts using partitioning and disjoint command conditions as much as possible.

  • 0 kudos
1 More Replies
aladda
by Databricks Employee
  • 7473 Views
  • 1 replies
  • 0 kudos
  • 7473 Views
  • 1 replies
  • 0 kudos
Latest Reply
aladda
Databricks Employee
  • 0 kudos

by default a delta table has stats collected on the first 32 columns. This setting can be configured using the following.set spark.databricks.delta.properties.defaults.dataSkippingNumIndexedCols = 3However there's a time trade-off to having a large n...

  • 0 kudos
aladda
by Databricks Employee
  • 1629 Views
  • 1 replies
  • 0 kudos
  • 1629 Views
  • 1 replies
  • 0 kudos
Latest Reply
aladda
Databricks Employee
  • 0 kudos

Its typically a good idea to run optimize aligned with the frequency of updates to the Delta Table. However you also don't want to over do as there's a cost/performance trade-off. Unless there are very frequent updates to the table that can cause sma...

  • 0 kudos
aladda
by Databricks Employee
  • 2247 Views
  • 1 replies
  • 0 kudos
  • 2247 Views
  • 1 replies
  • 0 kudos
Latest Reply
aladda
Databricks Employee
  • 0 kudos

Optimize merges small files into larger ones and can involve shuffling and creation of large in-memory partitions. Thus its recommended to use a memory optimized executor configuration to prevent spilling to disk. IN additional use of autoscaling wil...

  • 0 kudos
Labels