Databricks Community

Optimal Batch Size for Batch Insert Queries using JDBC for Delta Tables

Hi,I am currently experimenting with databricks-jdbc : 2.6.29 and trying to execute batch insert queries What is the optimal batch size recommended by Databricks for performing Batch Insert queries?Currently it seems that values are inserted row by r...

The functionality of table property delta.logRetentionDuration

We have one project requirement where we have to store only the 14 days history for delta tables. So for testing, I have set the delta.logRetentionDuration = 2 days using the below commandspark.sql("alter table delta.`[delta_file_path]` set TBLPROPER...

java.lang.SecurityException: Could not verify permissions for OverwritePartitionsDynamic RelationV2 - Delta tables dynamic partition overwrite on Databricks ACL enabled clusters

I'm working on Databricks ACL enabled clusters, and having trouble performing dynamic partition overwrite to Delta tables.I have created a test table using the following query:CREATE TABLE IF NOT EXISTS test_01 ( id STRING, name STRING, c...

is it possible to call columns of delta tables by their ordinal positions, if yes then how?

How to add the partition for an existing delta table

We didn't need to set partitions for our delta tables as we didn't have many performance concerns and delta lake out-of-the-box optimization worked great for us. But there is now a need to set a specific partition column for some tables to allow conc...

spark.read.parquet() - how to check for file lock before reading? (azure)

I have some python code which takes parquet files from an adlsv2 location and merges it into delta tables (run as a workflow job on a schedule)I have a try catch wrapper around this so that any files that fail get moved into a failed folder using dbu...

Is there any way to navigate/access cloud files using the direct abfss URI (no mount) with default python functions/libs like open() or os.listdir()?

Hello, Today on our workspace we access everything via mount points, we plan to change it to "abfss://" because of security, governance and performance reasons. The problem is sometimes we interact with files using "python only" code, and apparently ...

Can we use autoloader to stream files from delta tables(source)

What is the best practice while loading delta table , do I infer the schema or provide the schema?

I am loading avro files into the detla tables. I am doing this for multiple tables and some files are big like (2-3GB) and most of them are small like in few MBs.I am using autoloader to load the data into the delta tables.My question is:What is the ...

How to handle 100+ tables ETL through spark structured streaming?

I am writing a streaming job which will be performing ETL for more than 130 tables. I would like to know is there any other better way to do this. Another solution I am thinking is to write separate streaming job for all tables. source data is coming...

When to use delta lake versus relational database as a source for BI reporting?

Assume all of your data exists in delta tables and also in SQL server so you have a choice to report from either. Can someone share thoughts on "In what scenario you would not want report created from delta table and instead use the traditional rel...

Primary/Foreign key Costraints on Delta tables?

Hi All!I am using databricks in data migration project . We need to transform the data before loading it to SalesForce. Can we do Primary key/foreign key constraints on databricks delta tables?