Hi @Venu_DE1, The error message you’re encountering indicates that you’re trying to execute a query with streaming sources, but you’re missing the necessary .start() method for your streaming DataFrame.
Let’s address this issue step by step:
Streaming DataFrames and .writeStream:
- When working with streaming DataFrames, you need to use .writeStream instead of .write.
- The .writeStream method is specifically designed for streaming data and allows you to define the output sink (e.g., Delta table, file, etc.).
Using .writeStream.start():
- To start the streaming query, you should call .start() after defining your write stream.
- This method initiates the streaming process and ensures that the data is processed continuously.
Updating Your Code:
- Modify your code as follows to address the error:merge_sql = f""" -- Your merge command here """ delta_stream = spark.sql(merge_sql).writeStream \ .format("delta") \ .outputMode("append") \ .option("checkpointLocation", "bbbbb") \ .option("mergeSchema", "true") \ .option("path", "aaaaaaa") \ .start() # Add .start() to initiate the streaming process delta_stream.awaitTermination() # Wait for the streaming query to finish
Explanation:
- I’ve replaced the .toTable() method with .start() to correctly start the streaming process.
- The .awaitTermination() call ensures that the query runs until manually stopped.
Remember to adjust the placeholders ("bbbbb", "aaaaaaa", etc.) with the actual paths and table names specific to your use case.
Once you make these changes, your streaming merge operation should work as expected.
If you encounter any further issues, feel free to ask! 😊
