topic Re: auto loader in Data Engineering

auto loader

JissMathew — Tue, 12 Nov 2024 19:50:24 GMT

source_df = (spark.readStream

.format("cloudFiles")

.option("cloudFiles.format", "csv")

.option("header", "true")

.option("timestampFormat", "d-M-y H.m")

.option("cloudFiles.schemaLocation", f"{landing_folder_path}/Opportunity_schema")

#.option("cloudFiles.inferColumnTypes", "true")

.schema(schema) # Explicitly define schema to avoid invalid characters

.load(f"{landing_folder_path}/Opportunity")

)

source_df = source_df.filter("Id IS NOT NULL") # Example of filtering out corrupt data

write_query = (source_df.writeStream

.format("delta")

.option("checkpointLocation", f"{landing_folder_path}/Opportunity/checkpoint")

.option("mergeSchema", "false")

.outputMode("append")

.trigger(availableNow=True)

.toTable("dev.demo_db.Opportunity_raw")

)

write_query.awaitTermination() # Ensure the stream is running

ingest()
i have issue with auto loader that i can't getting incremental load on this . if rerun the ingest() the some unstructured data ingecting into Opportunity_raw

Re: auto loader

cgrant — Thu, 21 Nov 2024 22:51:27 GMT

Hi JissMatew,

As long as your checkpointLocation is not deleted and does not change, you should receive an incremental feed when loading data. Please verify that the checkpoint is not being deleted or moved between runs. The checkpoint is how the stream keeps track of its progress.

If you're still noticing this, please give more details about the duplicate unstructured data that you are ingesting.

Re: auto loader

NandiniN — Fri, 10 Jan 2025 07:01:18 GMT

In case of failures, Auto Loader can resume from where it left off by information stored in the checkpoint location and continue to provide exactly-once guarantees when writing data into Delta Lake. You don’t need to maintain or manage any state yourself to achieve fault tolerance or exactly-once semantics.

https://docs.databricks.com/en/ingestion/cloud-object-storage/auto-loader/index.html#how-does-auto-loader-track-ingestion-progress