Would like to know what would be the best way to handle the following scenario.
I have an azure cloud service uses a Azure storage table to lookup data against requests. The data in the table is generated offline periodically (once a week).
When new data is generated offline I would need to upload it into a separate table and make config changes (change table name) to the service to pick up data from the new table and re-deploy the service. (Every time data changes I change the table name - stored as a constant in my code - and re-deploy)
The other way would be to keep a configuration parameter for my azure web role which specifies the name of the table which holds current production data. Then, within the service I read the config variable for every request - get a reference to the table and fetch data from there.
Is the second approach above ok - or would it have a performance hit because I read the config, create a table client on every request that comes to the service. (The SLA for my service is less than 2 seconds)
To answer your question, 2nd approach is definitely better than the 1st one. I don't think you will take a performance hit because the config settings are cached on 1st read (I read it in one of the threads here) and creating table client does not create a network overhead because unless you execute some methods on the table client, this object just sits in the memory. One possibility would be to read from config file and put that in a static variable. When you change the config setting, capture the role environment changing event and update the static variable to the new value from the config file.
A 3rd alternative could be to soft code the table name in another table and have your application read the table name from there. You could update the table name as part of your upload process by first uploading the data and then updating this table with the new table name where data has been uploaded.