Read Write Variable Cannot access before PostExecute

I have a for each loop on a directory of files, each file has to be imported with a unique surrogate key added. For this I am selecting the max id that exists in the target table and assigning that value to a variable.

Within a script transformation I am copying this value to a variable declared in a script task, and incrementing it on each row processed. Obviously I now want to write this value back out to the higher scoped variable so it is available for the next file.

If I make the variable read write it is not even available for reading until the PostExecute. Is this correct or have I missed something?

To work round this I have created a second higher scoped variable that I can write to in the PostExecute and the other variable is passed in as read only and added another script task to update the variable values.Philip is a colleague of mine and we've just been taking a look at this.

The workaround is to use a multiflatfile adapter because the metadata of the files is identical.

Philip's requirement to be able to read a ReadWriteVariable in PreExecute() is, I feel, a valid one. Is there a reason that this cannot be done?

-Jamie|||You can actually access write-able variables anywhere you want just not the ones on the read/write list. The component has a VariableDispenser that you can lock variables for read and/or write and use them as you will. The limitation we place is only for the ones you specify in the ReadWriteVariables line and this was done to keep locking to a minimum. If we gave access during row processing then because we don't know the usage we would need to keep the variable locked during the entire ProcessInput call. If some other transform needed this variable as well then we have concurrency issues. This way the user can lock variables for write but has to do it explicitly so that it can be unlocked explicitly as well and hopefully the locking time can be kept to a minimum since the script author is controlling the locking.

HTH,
Matt

Read package variable in script component

For an SCD surrogate generator, I want to read a package variable that I've populated with the MAX () surrogate to begin my surrogate seed at. Does anyone have a piece of code sample to do this?

In your script component assign the variable in the properties of the component either to the readonly list or readWrite List. You can then access the variable in the script component with

Variables.myVariable

Where myVariable is the name of your variable.