Laravel: Column 'category_slug' cannot be null - php

Question

SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'category_slug' cannot be null (SQL: update products set category_slug = ?, products.updated_at = 2022-12-23 12:06:26 where id = 1)
How I get product category_slug colmun from category slug table.
Categories Table:
|id|name|slug |
|4 |Cat4|cat-4|
|5 |Cat5|cat-5|
|6 |Cat6|cat-6|
Products Table
|id|name|category_id|category_slug|
|1 |USDT|4 |cat-4 |
|2 |BTCH|5 |cat-5 |
|3 |EURT|6 |cat-6 |
Product Controller (Update Method)
public function update(Request $request)
{
$validator = Validator::make($request->all(), [
'name' => 'required|string|max:190',
'price' => 'required',
'category_id' => 'required',
])->validate();
$code=Product::find($request->id);
$code->name=$request->name;
$code->category_id=$request->category_id;
$code->category_slug=$request->category_slug;
$code->update();
return redirect()->back()->with('success',__('Product has been updated'));
}
`
Product Model
`
class Product extends Model
{
use HasFactory;
public function category()
{
return $this->hasOne(Category::class,'id','category_id');
}
`
I GET THIS ERROR
SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'category_slug' cannot be null (SQL: update products set category_slug = ?, products.updated_at = 2022-12-23 12:06:26 where id = 1)

Answer 1

I think you should not add the category_slug to your products table
you already have all the information you need about the product's category when you added the category_id to the products table
to get the category_slug from the product
you can do something like this
Product::with('category')->find(1)->category->slug

Answer 2

The problem lies here :
$code->category_slug=$request->category_slug;
It seems that $request->category_slug is null/undefined. If you are sure sending it from the frontend via an input make sure it has the right name attribute name="category_slug"
If however, you don't send it from frontend you should use slug helper to generate it from a string you chose, example:
$code->category_slug= \Str::slug($request->name . '-' .$request->category_id);
This will generate a slug from the name and id combined.
EDIT: If you want to get the current Product category slug you can use it like so:
$code->category_slug=$code->category->category_slug;
You might need to use $code->save() instead of update()

Answer 3

Change your migration.
public function up()
{
Schema::table('products', function (Blueprint $table) {
$table->string('category_slug')->nullable()->change();
});
}
It seems that you are not sending any value to the category_slug column while updating the record. The column must have a nullable constraint.