I'm trying to do a Data Flow using ADL1 as the source and Data Explorer as the sink; I can create the source but when I select Dataset for Sink Type the only available options in the Dataset pulldown are my ADL1 Datasets. If I use Data Copy instead I can choose Data Explorer as a sink but this won't work as Data Copy won't allow null values into Data Explorer number data types. Any insight on how to fix this?
I figured out a workaround. First I Data Copy the csv file into a staging table where all columns are strings. Then I Data Copy from staging table to production table using a KQL query that converts strings to their destination data types.
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I have a simple pipeline that loads data from a csv file to an Azure SQL db.
I have added a data flow where I have ensured all schema matches the SQL table. I have a specific field which contains numbers with leading zeros. The data type in the source - projection is set to string. The field is mapped to the SQL sink showing as string data-type. The field in SQL has nvarchar(50) data-type.
Once the pipeline is run, all the leading zeros are lost and the field appears to be treated as decimal:
Original data: 0012345
Inserted data: 12345.0
The CSV data shown in the data preview is showing correctly, however for some reason it loses its formatting during insert.
Any ideas how I can get it to insert correctly?
I had repro’d in my lab and was able to load as expected. Please see the below repro details.
Source file (CSV file):
Sink table (SQL table):
ADF:
Connect the data flow source to the CSV source file. As my file is in text format, all the source columns in the projection are in a string.
Source data preview:
Connect sink to Azure SQL database to load the data to the destination table.
Data in Azure SQL database table.
Note: You can all add derived columns before sink to convert the value to string as the sink data type is a string.
Thank you very much for your response.
As per your post the DF dataflow appears to be working correctly. I have finally discovered an issue with the transformation - I have an Azure batch service which runs a python script, which does a basic transformation and saves the output to a csv file.
Interestingly, when I preview the data in the dataflow, it looks as expected. However, the values stored in SQL are not.
For the sake of others having a similar issue, my existing python script used to convert a 'float' datatype column to string-type. Upon conversion, it used to retain 1 decimal number but as all of my numbers are integers, they were ending up with .0.
The solution was to convert values to integer and then to string:
df['col_name'] = df['col_name'].astype('Int64').astype('str')
my source is SQLDB
SINK :BLOB
SQL table have columns
in target file which i have creating blob initially no Header right. so customer given some Predefined Names so that data from sql column sholud be mapped those fileds.
in copy activity at mapping i need to map WITH proper data type and name which customer given
defaut its coming but i need ti map as i stated
HoW will i resolve it can some one help me
You can simply edit the sink header names, since its a TSV anyways
For addressing DataType mapping,
See, Data type mapping
Currently such data type conversion is supported when copying between
tabular data. Hierarchical sources/sinks are not supported, which
means there is no system-defined data type conversion between source
and sink interim types.
I would like to copy the data from local csv file to sql server in Azure Data Factory. The table in sql server is created already. The local csv file is exported from mysql.
When I use copy data in Azure Data Factory, there is an error "Exception occurred when converting value 'NULL' for column name 'deleted' from type 'String' to type 'DateTime'. The string was not recognized as a valid DateTime.
What I have done:
I checked the original value from column name 'deleted' is NULL, without quotes(i.e. not 'NULL').
I cannot change the data type during file format settings. The data type for all column is preset to string as default.
I tried to create data flow instead of copy data. I can change the data type from source projection. But the sink dataset cannot select sql server.
What can I do to copy data from CSV file to sql server via Azure Data Factory?
Data Flow doesn't support on-premise SQL. We can't create the source and sink.
You can use copy active or copy data tool to do that. I made an example data which delete is NULL:
As you said the delete column data is Null or contains NULL, and ALL will be considered as String. The key is that your Sink SQL Server table schema if it allows NULL.
I tested many times and it all works well.
Azure Data factory V2 - Copy Activity - Copy data from Changing Column names and number of columns to Destination. I have to copy data from a Flat File where number of Columns will change in each file and even the column names. How do I dynamically map them in Copy Activity to load the data into destination in Azure Data factory V2.
Suppose my destination has 20 columns, but source will come sometimes as 10 columns or 15 or sometimes 20. If the source columns are less than destination then remaining column values in destination should be passed as Null.
Use data flows in ADF. Data Flow sinks can generate the table schema on the fly if you wish. Or you can just "auto-map" any changing schema to your target. If your source schema changes often, just use "schema drift" with no schema defined in your dataset.
I have a "Copy" step in my Azure Data Factory pipeline which copies data from CSV file to MSSQL.
Unfortunately, all columns in CSV comes as String data type. How can I change these data types to match the data type in SQL table.
Here is how the data is available in CSV file.
I would like to change data type of WIPStateKey to Integer and ReportDt to Timestamp. I do not seem to find an option to achieve this.
Yes as you said "all columns in CSV comes as String data type".
But when using a copy active, choose the csv file as the source, we can import the schema and change the column data type.
I created a demo.csv file for test:
I copy data from my demo.csv file to my Azure SQL database.
During file format setting, we can change the column data type:
Table mapping:
Column mapping:
Copy completed:
Hope this helps