Python script + php + mysql + json-rpc

I have a mysql database. In this database are several fields (columns). It is automatically updated (new rows) when people fill in a form on our website. It has a couple of blank fields. I would like for: 1. a php script which allows information to be passed in the url, like this: [login to view URL] the php script will then 1. check the database to look for that email address 2. If the email address does not exist then return some error. 3. If it does exist, then check if the id field is blank/null 4. if it is blank/null then update the id to whatever is in the url. and return a verified message. 5. if it is not blank/null then return error that it has already been claimed (or verified). Python script: This will continuously check the database (i can setup a cron for once every minute or 2) for all records that do not have a specific value in one of the columns. for example sent=null so like this when script is run: 1. lookup all records which have sent=null (or not yes/1) and have id is not null 2. execute json-rpc call to our server with a command based on information in the records it found. e.g. create account bob send 100 credits sdfjsdfdslfsdlfsdlf the account is in the record and the id is in the record. 3. Check what is returned: 4. if successful a long string of letters and numbers will be returned. Update the record with this string, and update sent=1 5. if an error returns that is = this account already exist, then append a "x" to the account name and repeat for that record, until it is accepted. Then update the record with the string and update sent=1 and also update "givenname" field to the name that was used, example bobxx 6. If any other error returns then end the script. all actions need to be properly synchronised/atomic.