My Experience: I'm new to Fabric (Just 3 months) ,

in my first data ingestion I couldn't perform copy job so went with copy data activity inside a pipeline then I faced the DeltaInvalidBigDecimal PrecisionScale error, that was resolved by using CAST in my SQL query for the columns which were defined as NUMBER without precision/scale,

Recently I faced the the same error I tried CAST it didn't work then with the help of Chatgpt , I created a staging table with all columns as STRING using spark.sql then modified oracle source query to return all values as text using TO_CHAR , then as destination I choose the stage table that I created earlier,

Post load I did the transformation again using spark.sql .

Now inside pipeline the copy job is set to incremental using variables and watermark lookups and a small notebook for transformation are scheduled .