如何正确转义Active Record where子句中的正则表达式

Question

I am using Active Record v4.2.1 to query a mySQL database using a regular expression. I would like to create the following SQL:

SELECT `users`.* FROM `users` WHERE (email REGEXP '[@\.]gmail\.com')

However, I cannot seem to find the correct way to create the SQL using Active Record.

---

User.where("email REGEXP ?", "[@.]gmail.com").to_sql

yields

"SELECT `users`.* FROM `users` WHERE (email REGEXP '[@.]gmail.com')"

---

User.where("email REGEXP ?", "[@\.]gmail\.com").to_sql

yields

"SELECT `users`.* FROM `users` WHERE (email REGEXP '[@.]gmail.com')"

---

User.where("email REGEXP ?", "[@\\.]gmail\\.com").to_sql

yields

"SELECT `users`.* FROM `users` WHERE (email REGEXP '[@\\\\.]gmail\\\\.com')"

---

How do I get Active Record to properly escape the SQL?

Answer 1

The escaping just looks wrong in the console when using to_sql , your last example actually sends this to MySQL:

SELECT `users`.* FROM `users` WHERE (email REGEXP '[@\\.]gmail\\.com')

You can confirm this by running the actual query in the console and checking the log file.