SSIS Excel Data Source - Is it possible to override column data types?
When an excel data source is used in SSIS, the data types of each individual column are derived from the data in the columns. Is it possible to override this behaviour?
Ideally we would like every column delivered from the excel source to be string data type, so that data validation can be performed on the data received from the source in a later step in the data flow.
Currently, the Error Output tab can be used to ignore conversion failures - the data in question is then null, and the package will continue to execute. However, we want to know what the original data was so that an appropriate error message can be generated for that row.
Answer
Yes, you can. Just go into the output column list on the Excel source and set the type for each of the columns.
To get to the input columns list right click on the Excel source, select 'Show Advanced Editor', click the tab labeled 'Input and Output Properties'.
A potentially better solution is to use the derived column component where you can actually build "new" columns for each column in Excel. This has the benefits of
- You have more control over what you convert to.
- You can put in rules that control the change (i.e. if null give me an empty string, but if there is data then give me the data as a string)
- Your data source is not tied directly to the rest of the process (i.e. you can change the source and the only place you will need to do work is in the derived column)