我想在 Laravel 中创建一个功能

Question

我想在 Laravel 上创建一个功能，用于检查数据库 table 的行是否存在。检查后，根据检查结果，删除、添加新列或跳过它们。

foreach($this->category_product as $k => $item) {
        $category_product = CategoryProduct::where([['category_id', $this->category_id],['product_id', $k]])->firstOr(function () {
                $category_product = CategoryProduct::create([
                        'category_id' => $this->category_id,
                        'product_id' => $k
                ]);
        });
}

这是我目前所拥有的。如何删除查询中不存在的行？任何帮助，将不胜感激。谢谢

Answer 1

我希望我没听错，因为问题还不够清楚，但如果行存在，这里有一种删除行的方法：

注意：你错过了use ($k)

foreach ($this->category_product as $k => $item) {
    $category_product = CategoryProduct::where([
        ['category_id', $this->category_id],
        ['product_id', $k]
    ])->firstOr(function () use ($k) {
        // Delete if it exists.
        CategoryProduct::where([
            'category_id' => $this->category_id,
            'product_id' => $k
        ])->delete();

        // Create if it doesn't exist.
        $category_product = CategoryProduct::create([
            'category_id' => $this->category_id,
            'product_id' => $k
        ]);

    });
}

我想在 Laravel 中创建一个功能

I want to create a functionality in Laravel

php

database

arrays

foreach

laravel