schema inference in Synapse Analytics

What is meant by schema inference.And please explain me with example.But i am not able to find the proper example for this schema inference.

Thanks in advance

Azure Synapse Analytics

An Azure analytics service that brings together data integration, enterprise data warehousing, and big data analytics. Previously known as Azure SQL Data Warehouse.

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PRADEEPCHEEKATLA-MSFT 88,561 Reputation points • Microsoft Employee 2021-06-03T10:48:49.037+00:00 Hello @Rohit Kulkarni , Thanks for the question and using MS Q&A platform.

What is schema inference?

Infer schema will automatically guess the data types for each field.

In Azure Synapse Analytics, schema inference works only for parquet format.

For other formats:

Infer schema will automatically guess the data types for each field. If we set this option to TRUE, the API will read some sample records from the file to infer the schema.

To example, in more details I had create two dataframe one with inferschema=’False’ and another inferschema=’True’ with a sample data.

df_without_schema without inferschema (If you look at the schema of the dataframe, every data type is treated as string).
df_with_schema with inferschema=‘True’ (If you look at the schema of the dataframe, it automatically detected the data types).

Hope this helps. Do let us know if you any further queries.

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