What is Database Query Builder in Laravel?
Why Interviewers Ask This
Interviewers use this question to quickly assess whether a candidate has the foundational knowledge required for Laravel development. It reveals whether you understand the building blocks that more complex concepts rely on.
Answer
The Query Builder provides a fluent, database-agnostic interface for constructing and executing SQL queries without writing raw SQL. Access via the DB facade: DB::table("users")->where("active", 1)->orderBy("name")->get(). Key methods: select(), where(), orWhere(), whereIn(), whereBetween(), whereNull(), join(), leftJoin(), orderBy(), groupBy(), having(), limit(), offset(), insert(), update(), delete(), count(), max(), min(), avg(), sum(). Use DB::raw() for raw SQL expressions. The Query Builder automatically handles parameter binding to prevent SQL injection.
Pro Tip
Demonstrate both theoretical understanding and practical experience. Say what it is, then give an example of how you actually used it in a Laravel codebase.