What does 'mysql_query()' return on failure?

Solution (By Examveda Team)

This question asks about how the `mysql_query()` function in MySQL behaves when it encounters an error.

`mysql_query()` is used to execute SQL statements in your database. When everything goes smoothly, it returns a value indicating success.

But what happens if something goes wrong? Maybe your SQL statement has a syntax error, or you're trying to access data you don't have permission to see. This is where the error handling comes in.

Let's break down the options:

Option A: 0
This is a common return value for success in many programming languages. However, `mysql_query()` does *not* use 0 to indicate success in MySQL.

Option B: 1
Similar to option A, 1 is often associated with success in other contexts. But in MySQL's `mysql_query()`, it doesn't represent a successful query.

Option C: -1
This is getting closer! `mysql_query()` returns -1 when an error occurs during the query execution.

Option D: a non-zero value
This is actually the correct answer. `mysql_query()` returns a non-zero value when an error occurs. The specific value might be -1, but it could also be something else depending on the exact error.

In summary:
* When your SQL statement runs without problems, `mysql_query()` returns a value indicating success (usually a resource identifier).
* If `mysql_query()` encounters an error, it returns a non-zero value (often -1) to signal that something went wrong.

The correct answer is Option D: a non-zero value.