Here are a few question-based titles that fit the content of your article: * **Laravel Database Constraint Error: Why Can\'t I Delete a Post with Likes?** * **Deleting Parent Rows in Laravel: How to

Database Constraint Error in Laravel: "Cannot Delete or Update a Parent Row"

A common error encountered in Laravel is "SQLSTATE[23000]: Integrity constraint violation: 1451 Cannot delete or update a parent row." This error occurs when trying to delete a row from a parent table that has child rows in a related table.

In your case, you are experiencing this error when attempting to delete a post that has associated likes. This is because the likes table has a foreign key constraint that references the posts table. When you try to delete a post, it cannot be deleted because there are still records in the likes table that depend on it.

To resolve this error, you can modify your database schema to use onDelete('cascade'). This will automatically delete the associated child records when the parent record is deleted.

Updated Likes Schema with onDelete('cascade'):

<code class="php">Schema::create('likes', function (Blueprint $table) {
    $table->increments('id');
    $table->integer('post_id')->unsigned();
    $table->foreign('post_id')->references('id')->on('posts')->onDelete('cascade');
});</code>

Alternatively, you can manually delete the associated child records before deleting the parent record. In your Laravel model, you can use the following code to do this:

<code class="php">$post->likes()->delete();
$post->delete();</code>

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