laravel Eloquent - 使用字符串值而不是列标题连接子句
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Eloquent - join clause with string value rather than column heading
提问by benJ
I have a question regarding join clauses in Eloquent, and whether you can join on a string value rather than a table column.
我有一个关于 Eloquent 中连接子句的问题，以及是否可以连接字符串值而不是表列。
I have the code below querying a nested set joining parent/child records in a table 'destinations' via a table 'taxonomy'.
我有下面的代码通过表“分类法”查询连接表“目的地”中的父/子记录的嵌套集。
The second $joinstatement in the closure is the one causing an issue; Eloquent assumes this is a column, when I would actually just like to join on t1.parent_type = 'Destination'- ie, t1.parent_typeshould = a string value, Destination.
$join闭包中的第二个语句是导致问题的语句；Eloquent 假设这是一个列，而我实际上只是想加入t1.parent_type = 'Destination'- 即，t1.parent_typeshould = 一个字符串值，Destination.
$result = DB::connection()
->table('destinations AS d1')
->select(array('d1.title AS level1', 'd2.title AS level2'))
->leftJoin('taxonomy AS t1', function($join) {
$join->on('t1.parent_id', '=', 'd1.id');
$join->on('t1.parent_type', '=', 'Destination');
})
->leftJoin('destinations AS d2', 'd2.id', '=', 't1.child_id')
->where('d1.slug', '=', $slug)
->get();
Is it possible to force Eloquent to do this? I've tried replacing 'Destination'with DB::raw('Destination')but this does not work either.
是否可以强制 Eloquent 这样做？我试过替换为'Destination'，DB::raw('Destination')但这也不起作用。
Thanking you kindly.
谢谢你。
回答by mukund
Another best way to achieve same is :
实现相同目标的另一种最佳方法是：
$result = DB::connection()
->table('destinations AS d1')
->select(array('d1.title AS level1', 'd2.title AS level2'))
->leftJoin('taxonomy AS t1', function($join) {
$join->on('t1.parent_id', '=', 'd1.id');
$join->where('t1.parent_type', '=', 'Destination');
})
->leftJoin('destinations AS d2', 'd2.id', '=', 't1.child_id')
->where('d1.slug', '=', $slug)
->get();
Replace your onwith where
替换你on的where
回答by Krishna Raj K
try using DB::raw("'Destination'")
尝试使用 DB::raw("'Destination'")
