如何在laravel php内连接表

Question

I have this query which is

SELECT * FROM books b 
INNER JOIN categories c ON b.category_id = c.id 
WHERE c.category_name = 'Comics'

thus is passed by parameter

SELECT * FROM books b 
INNER JOIN categories c ON b.category_id = c.id 
WHERE c.category_name = ?

I tried in Laravel like this

writer::join('categories','categories.id','=','writers.category_id')
  ->where('categories.category_name','Comics')
  ->get();

And with parameter

writer::join('categories','categories.id','=','writers.category_id')
  ->where(['categories.category_name' => $cat])
  ->get();

I didn't get any data in Laravel! Is there any mistake I am doing?

Answer 1

Try this instead:

writer::join('categories','categories.id','=','writers.category_id')
->where([
  ['categories.category_name', '=', $cat]
])->get();

or

writer::join('categories','categories.id','=','writers.category_id')
->where('categories.category_name', $cat)
->get();