I am trying to load a big file which basically is a json format flat file from my local drive to SQL Server by using SSIS. It's a one line file and I don't need to specify columns and rows as I am going to parse it as soon as it's in SQL Server by OPENJSON.

but when I tried to create Flat File Source in Visual Studio SSIS, I was not able to do that as even I used 'fixed width' format according to the solution here:

Click back to Import Column Input and find the column name. Scroll down to the Custom Properties and use the LineageID above for FileDataColumnID where it says 0. Otherwise, you have an error of

The "Import Column.Outputs[Import Column Output].Columns[FileContent]" is not referenced by any input column. Each output column must be referenced by exactly one input column.

OLE DB Destination

Any data sink will do but the important thing will be to map our column from the previous step to a n/varchar(max) in the database.