使用 laravel query builder + mysql 从两个表中查询

Question

我有两个表，一个叫报价单，另一个叫发票。我想检索所有没有发票的报价单。下面是我到目前为止的代码。我只能检索所有报价。如何修改此查询

$quotations = Quotation::lists('id', 'id');

mysql> describe quotations;
+---      ----  --------+------------------+------+-----+---------------------+-----------------------------+
| Field         | Type             | Null | Key | Default             | Extra                       |
+---------------+------------------+------+-----+---------------------+-----------------------------+
| id            | int(10) unsigned | NO   | PRI | NULL                | auto_increment              |
| customer_id   | int(10) unsigned | NO   | MUL | NULL                |                             |
| employee_id   | int(10) unsigned | NO   | MUL | NULL                |                             |
| exchange_rate | int(11)          | NO   |     | 0                   |                             |
| remark        | varchar(255)     | NO   |     |                     |                             |
| created_at    | timestamp        | NO   |     | CURRENT_TIMESTAMP   | on update CURRENT_TIMESTAMP |
| updated_at    | timestamp        | NO   |     | 0000-00-00 00:00:00 |                             |
+---------------+------------------+------+-----+---------------------+-----------------------------+
mysql> describe invoices;
+--------------+------------------+------+-----+---------------------+-----------------------------+
| Field        | Type             | Null | Key | Default             | Extra                       |
+--------------+------------------+------+-----+---------------------+-----------------------------+
| id           | int(10) unsigned | NO   | PRI | NULL                | auto_increment              |
| quotation_id | int(10) unsigned | NO   | MUL | NULL                |                             |
| employee_id  | int(10) unsigned | NO   | MUL | NULL                |                             |
| amount       | int(11)          | NO   |     | 0                   |                             |
| balance      | int(11)          | NO   |     | 0                   |                             |
| created_at   | timestamp        | NO   |     | CURRENT_TIMESTAMP   | on update CURRENT_TIMESTAMP |
| updated_at   | timestamp        | NO   |     | 0000-00-00 00:00:00 |                             |
+--------------+------------------+------+-----+---------------------+-----------------------------+

Answer 1

您可以使用以下内容：

Quotation::has('invoices', '<', 1)->get();

以上代码假定您在 Quotation 模型中建立了关系，即：

class Quotation 
{
    public function invoices()
    {
        return $this->hasMany('\Models\Invoice');
    }
}

has 方法将检查您定义为第一个参数 invoices 的关系中的项目总数。第二个参数是小于的比较，第三个是你要比较的计数。因此，这将搜索发票数量少于 1 的所有报价单。

您可以在查询关系存在下阅读更多内容about querying relations here。

Answer 2

感谢 Emn1ty

，我通过添加下面的代码让它工作

$quotations = Quotation::has('taxInvoices', '<', 1)->get();

使用 laravel query builder + mysql 从两个表中查询

query from two tables using laravel query builder + mysql

laravel

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