Flow Control in SSIS

I am having a hard time with what appears to be something simple. I want to import an excel spreadsheet into a table on a daily basis from a command line. I created a package from the Import Wizzard in the SQL Management Studio and saved it. Since I want a clean table each day, my process needs to be create a temp table, import from the Excel file into the temp table. If that is successful, delete the original table and rename the temp table the original name. The point of this process is to provide for a fail-safe if there is some unforseen problem downloading the data on a particular day.

When I run the package, the first thing it does is delete the original table. I know this because the process shows the time that it finished is before anything else has started or finished. The time shown for the completion of the data flow task is about 2 minutes after that time.

This is maddening!!! The one thing I do not want to happen I can not seem to prevent. I have my control flow set on success. Why does it do this?

Are you using precedence constraints? You should have a flow like:

Create temp table(Execute SQL task) -- load temp table (Dataflow) --> delete orig. table & rename temp (Execute SQL Task)

The precedence constraint should be set upon success of the previous task

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Thanks for the reply. I was using contraints and what you descibe is how I put it in my original message. However, after a good night's sleep I see that in my package I the drop table task comes after the table is renamed, rather than before. It appears SSIS was trying its best to complete all those items the best it could.

After putting all in correct order, the package ran as it should.