Was the SMS directed a you (ie know your name, etc) or did it seem generic? If it was a Phishing scam, it's unlikely the spammers/scammers hacked any databases.
I understand the text message might have been directed at Fido customers. However, it's actually rather easy to target a specific group of customers. All phone numbers -- whether landline or mobile -- are in databases which are readily available online. Certain prefixes are designated as landlines, others as Rogers, Fido, Bell, etc (see here). All someone needs to do is pick an area code and prefix and let a computer sequentially send those numbers from 0000 to 9999 text messages and all of those customers would be with the desired targeted provider.
There have even been cases where former customers, who have ported out their numbers to other providers, have received SPAM SMS targeted at their previous providers. Since those online phone number databases are not updated with ported number information, that's evidence that actual provider database information has not been hacked.
**edit** You can also forward the message to 7726 (SPAM). This will submit the messages to be audited and potentially blocked from the network if confirmed to be spam (see here).**
Hope this helps 😀