Data Flow Sink is generating zero byte files at each folder location - azure-data-factory

In one of the data factory which I am currently using, the data flow sink generates file at every folder location.
Suppose I want to generate a csv as MyData.csv inside Folder1/Folder2/ location.
It does generates MyData.csv inside Folder1/Folder2 location but additionally it generates zero byte file at every Folder location. So my hierarchy looks something like below
/Folder1/Folder2 (0 byte file)
/Folder1 (0 byte file)
/Folder1/Folder2/MyData.csv (Desired Output)
In old Data factory I was not facing the above issue, I checked the data set and linked service connection. Everything is same. Also checked whether the storage account has a problem, but using the same storage account but different data factory, issue persists. Kindly give suggestions

Related

Azure Data Factory - run script on parquet files and output as parquet files

In Azure Data Factory I have a pipeline, created from the built-in copy data task, that copies data from 12 entities (campaign, lead, contact etc.) from Dynamics CRM (using a linked service) and outputs the contents as parquet files in account storage. This is run every day, into a folder structure based on the date. The output structure in the container looks something like this:
Raw/CRM/2022/05/28/campaign.parquet
Raw/CRM/2022/05/28/lead.parquet
Raw/CRM/2022/05/29/campaign.parquet
Raw/CRM/2022/05/29/lead.parquet
That's just an example, but there is a folder structure for every year/month/day that the pipeline runs, and a parquet file for each of the 12 entities I'm retrieving.
This involved creating a pipeline, dataset for the source and dataset for the target. I modified the pipeline to add the pipeline's run date/time as a column in the parquet files, called RowStartDate (which I'll need in the next stage of processing)
My next step is to process the data into a staging area, which I'd like to output to a different folder in my container. My plan was to create 12 scripts (one for campaigns, one for leads, one for contact etc.) that essentially does the following:
accesses all of the correct files, using a wildcard path along the lines of: Raw/CRM/ * / * / * /campaign.parquet
selects the columns that I need
Rename column headings
in some cases, just take the most recent data (using the RowStartDate)
in some cases, create a slowly changing dimension, ensuring every row has a RowEndDate
I made some progress figuring out how to do this in SQL, by running a query using OPENROWSET with wildcards in the path as per above - but I don't think I can use my SQL script in ADF to move/process the data into a separate folder in my container.
My question is, how can I do this (preferably in ADF pipelines):
for each of my 12 entities, access each occurrence in the container with some sort of Raw/CRM///*/campaign.parquet statement
Process it as per the logic I've described above - a script of some sort
Output the contents back to a different folder in my container (each script would produce 1 output)
I've tried:
Using Azure Data Factory, but when I tell it which dataset to use, I point it to the dataset I created in my original pipeline - but this dataset has all 12 entities in the dataset and the data flow activity produces the error: "No value provided for Parameter 'cw_fileName" - but I don't see any place when configuring the data flow to specify a parameter (its not under source settings, source options, projection, optimize or inspect)
using Azure Data Factory, tried to add a script - but in trying to connect to my SQL script in Synapse - I don't know my Service Principal Key for the synapse workspace
using a notebook Databricks, I tried to mount my container but got an error along the lines that "adding secret to Databricks scope doesn't work in Standard Tier" so couldn't proceed
using Synapse, but as expected, it wants things in SQL whereas I'm trying to keep things in a container for now.
Could anybody point me in the right direction. What's the best approach that I should take? And if its one that I've described above, how do I go about getting past the issue I've described?
Pass the data flow dataset parameter values from the pipeline data flow activity settings.

Azure Data Factory data flow file sink

I am using a .csv file to import data into an Azure SQL database. After the data import is complete I am now moving the source file from the Source container to myArchive container. I am now trying to save the filename as SaleData_yyyyMMdd_HHmm.csv, but, I have the folder with this name getting created and the file is broken down into multiple part files (part-00000-, part-00001-,...). Could you please guide me on how to specify the filename with current data & timestamp.
File System: myArchive
Folder Path: concat('SalesDepartment/Warehouse1/','SaleData_',toString(currentTimestamp(),'yyyyMMdd_HHmm'),'.csv')
Folder path can be mentioned directly in the sink dataset. (Note, my source and sink both are delimited type)
For filename,
Under sink data set, create a parameter to pass file name and use it in the file name portion of dataset.
Use the below expression in copy activity sink's parameter value
#concat('SaleData_',formatDateTime(utcnow(),'yyyyMMdd_HHmm'),'.csv')
Remember, this just copies your source in a different name. We need to add a delete activity to delete the original source file.
If you are using a dataflow,
make sure you are choosing single partition in the optimize tab of Sink instead of Use current Partitioning.
Then, go to Settings, choose Output to SIngle file. Under filename, mention the expression with timestamp.
concat('SaleData_',toString(currentUTC('yyyyMMdd_HHmm')),'.csv')

How can I pass output from a filter activity directly to a copy activity in ADF?

I have 4000 files each averaging 30Kb in size landing in a folder on our on premise file system each day. I want to apply conditional logic (several and/or conditions) against details in their file names to only move files matching the conditions into another folder. I have tried linking a meta data activity which gets all files in the source folder with a filter activity which applies the conditional logic with a for each activity with an embedded copy activity. This works but it is taking hours to process the files. When running the pipeline in debug the output window appears to list each file copied as a line item. I’ve increased the batch count setting in the for each to 50 but it hasn’t improved things. Is there a way to link the filter activity directly to the copy activity without using for each activity? Ie pass the collection from the filter straight into copy’s source. Alternatively, some of our other pipelines just use the copy activity pointing to a source folder and we configure its filefilter setting with a simple regex using a combination of * and ?, which is extremely fast. However, in this particular scenario, my conditional logic is more complex and I need to compare attributes in each file’s name with values to decide if the file should be moved. The filefilter setting allows dynamic content so I could remove the filter activity completely, point the copy to the source folder and put the conditional logic in the filefilter’s dynamic content area but how would I get a reference to the file name to do the conditional checks?
Here is one solution:
Write array output as text to a .json in Blob Storage (or wherever). Here are the steps to make that work:
Copy Data Source:
Copy Data Sink:
Write the json (array output) to a text file that has the name of the files you want to copy.
Copy Activity Source (to get it from JSON to .txt):
Sink will be .txt file in your Blob.
Use that text file in your main copy activity and use the following setting:
This should copy over all the files that you identified in your Filter Activity.
I realize this is a work around, but really is the only solution for what you are asking. Otherwise there is no way to link a filter activity straight to a copy activity.

Can a Mapping Data Flow use a parameterized Parquet dataset?

thanks for coming in.
I am trying to develop a Mapping Data Flow in an Azure Synapse workspace (so I believe that this can also apply to ADFv2) that takes a Delta input and transforms it straight into a Parquet -formatted output, with the relevant detail of using a Parquet dataset pointing to ADLSGen2 with parameterized file system and folder, in opposition to a hard-coded file-system and folder, because this would take creating too many datasets as there are too many folders of interest in the Data Lake.
The Mapping Data Flow:
As I try to use it as a Source in my Mapping Data Flows, the debug configuration (as well as the parent pipeline configuration) will duly ask for my input on those parameters, which I am happy to enter.
Then, as soon I try to debug or run the pipeline I get this error in less than 1 second:
{
"Message": "ErrorCode=InvalidTemplate, ErrorMessage=The expression 'body('DataFlowDebugExpressionResolver')?.50_DeltaToParquet_xxxxxxxxx?.ParquetCurrent.directory' is not valid: the string character '_' at position '43' is not expected."
}
RunId: xxx-xxxxxx-xxxxxx
This error message is not very specific to know where I should look.
I tried replacing the parameterized Parquet dataset with a hard-coded one, and it works perfectly both in debug and pipeline -run modes. However, this does not gets me what I need which is the ability to reuse my Parquet dataset instead of having to create a specific dataset for each Data Lake folder.
There are also no spaces in the Data Lake file system. Please refer to these parameters that look a lot like my production environment:
File System: prodfs001
Directory: synapse/workspace01/parquet/dim_mydim
Thanks in advance to all of you, folks!
The directory name synapse/workspace01/parquet/dim_mydim has an _ in dim_mydim, can you try replacing the underscore, or maybe you can use dimmydim to test whether it works.

Azure Data factory, How to incrementally copy blob data to sql

I have a azure blob container where some json files with data gets put every 6 hours and I want to use Azure Data Factory to copy it to an Azure SQL DB. The file pattern for the files are like this: "customer_year_month_day_hour_min_sec.json.data.json"
The blob container also has other json data files as well so I have filter for the files in the dataset.
First question is how can I set the file path on the blob dataset to only look for the json files that I want? I tried with the wildcard *.data.json but that doesn't work. The only filename wildcard I have gotten to work is *.json
Second question is how can I copy data only from the new files (with the specific file pattern) that lands in the blob storage to Azure SQL? I have no control of the process that puts the data in the blob container and cannot move the files to another location which makes it harder.
Please help.
You could use ADF event trigger to achieve this.
Define your event trigger as 'blob created' and specify the blobPathBeginsWith and blobPathEndsWith property based on your filename pattern.
For the first question, when an event trigger fires for a specific blob, the event captures the folder path and file name of the blob into the properties #triggerBody().folderPath and #triggerBody().fileName. You need to map the properties to pipeline parameters and pass #pipeline.parameters.parameterName expression to your fileName in copy activity.
This also answers the second question, each time the trigger is fired, you'll get the fileName of the newest created files in #triggerBody().folderPath and #triggerBody().fileName.
Thanks.
I understand your situation. Seems they've used a new platform to recreate a decades old problem. :)
The patter I would setup first looks something like:
Create a Storage Account Trigger that will fire on every new file in the source container.
In the triggered Pipeline, examine the blog name to see if it fits your parameters. If no, just end, taking no action. If so, binary copy the blob to a account/container your app owns, leaving the original in place.
Create another Trigger on your container that runs the import Pipeline.
Run your import process.
Couple caveats your management has to understand. You can be very, very reliable, but cannot guarantee compliance because there is no transaction/contract between you and the source container. Also, there may be a sequence gap since a small file can usually process while a larger file is processing.
If for any reason you do miss a file, all you need to do is copy it to your container where your process will pick it up. You can load all previous blobs in the same way.