Benchmark: Qry vs id - MeasureThat.net

HTML Preparation code:

<div id='a'></div>

Tests:

Id
document.getElementById('a')
Query
document.querySelector('#a')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Id
Query

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is tested, compared options, pros and cons of those approaches, and other considerations.

**Benchmark Definition and Preparation Code**

The provided Benchmark Definition json represents a simple benchmark that tests two different ways to retrieve an element with a specific ID or query selector.

The Script Preparation Code is empty, which means that the script being tested does not require any setup or initialization. This allows for a clean and straightforward comparison of the two methods.

The Html Preparation Code provides a basic HTML structure with an `<div>` element assigned to the `id` "a" attribute. This ensures that both methods can successfully retrieve the element being tested.

**Individual Test Cases**

There are only two test cases:

1. **Id**: Retrieves the element using `document.getElementById('a')`.
2. **Query**: Retrieves the element using `document.querySelector('#a')`.

**Comparison of Id and Query Methods**

The two methods differ in how they approach finding the target element.

*   **Id Method (`document.getElementById('a')`)**:
    *   Pros:
        *   More efficient, as it uses a direct reference to the element by its ID.
        *   Often faster due to the browser's ability to cache this result.
    *   Cons:
        *   Less flexible, as it only works if the element has a unique `id` attribute.
        *   May not work for elements with dynamic or changing IDs.

*   **Query Method (`document.querySelector('#a')`)**:
    *   Pros:
        *   More flexible, as it allows retrieval of elements based on more complex selectors (e.g., class names, tag names).
        *   Can handle elements without a `id` attribute.
    *   Cons:
        *   Less efficient due to the need to parse and evaluate the CSS selector.
        *   May be slower if the browser needs to perform additional computations.

**Library Usage**

The provided benchmark uses none, as it does not rely on any external libraries. However, some JavaScript frameworks or libraries might use similar APIs for retrieving elements, which could impact performance.

**Special JS Features or Syntax**

There are no special JavaScript features or syntax used in the provided benchmark.

Related benchmarks:

Qry vs id (version: 0)

Comparing performance of: Id vs Query

Created: 3 years ago by: Guest

Jump to the latest result

Id

Query

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):