insert new tag create by user into my table(database) by php

Question

I'm currently building a blog system and here is my question.

I provide several basic tags(using checkbox) for users to select.

In the same time user can also insert a new tag by clicking the button of NEW TAG!.

here is my code.

$newestTags = 0;

$title = $_POST['blog_title'] ?? '';
$content = $_POST['blog_content'] ?? '';
$tagValue = $_POST['tags'] ?? '';
$newTagFromhtml = $_POST['inserttag'] ?? '';

$totalBlog = $pdo->query("SELECT COUNT(*) from `blog`")->fetch(PDO::FETCH_NUM)[0];
$newestBlog = intval($totalBlog) + 1;

$sql = "INSERT INTO `blog`(`blog_id`,`blog_title`,`blog_content`)
                VALUES(?,?,?)";  

$stmt = $pdo->prepare($sql);

$stmt->execute([
   $newestBlog,
   $title,
   $content,
]);

$tagsInsert = "INSERT INTO `blog_tagtoblog`(`tags_ID`, `blog_ID`) VALUES (?,?)";

$tags = $pdo->prepare($tagsInsert);

foreach($tagValue as $value){
  $tags->execute([
    $value,
    $newestBlog,
 ]);
}

and here is my table for blog and tag

blog_tagstoblog	tags_id	blog_id
1	1	22
2	1	23
3	2	22

tags_id	tags_desc
1	food
2	lunch

also my HTML and Javascript

<p>TAGS!</p>
<?php foreach($tags as $t): ?>
<div>
    <input type="checkbox" class="checkbox" name="tags[]" value="<?= $t['tags_id']?>" id="<?= $t['tags_id']?>">
    <label for="<?= $t['tags_id']?>" class="form-label" id="haha"> <?= $t['tags_desc']?></label>
</div>
<? endforeach; ?>
<button class="insertNewTag">NEW TAG!</button>
</div>

<button type="submit" class="btn btn-primary">submit</button>

// javascript down below

insertNewTag.addEventListener("click", function(e) {
    e.preventDefault();
    input.type = "text";
    input.name = "tags[]"
    input.value = input.value;
    spaceForNewTag.append(input);

fetch("insertArticle-api.php", {
    method: 'POST',
    body: fd,
}).then(res => res.json()).then(obj => {
    if (obj.success || obj.tagsCheck) {
        console.log(obj)
        alert("OKAY!")
        location.href = "articleList.php";
} else {
    alert(`${obj.error}`)
}
})
})

and now my question is,

it's okay for me to insert tag that I use foreach to loop over into tagstoblog and insert tags that created by user into table of tag.

But I don't know how to fetch the tags_id of newest tag created by user and insert it into table of blog_tagstoblog.

It is possible to do that in one go?

Answer 1

You can use $last_insert_id = $pdo->lastInsertId(). Then if need, you can use it as json response and call anywhere you need.