I have a table in my database called JobCardOps and a model JobCardOp.php. Fields of this table include OpNum, JobCardNum, PrevOpNum, OpStatus. An row is uniquely identified by the JobCardNum and OpNum pair. Now, I considered having another field called PreviousOpStatus which contains the status of the previous Op, by then I wondered whether I could do this with Join.
So to clarify, When I retrieve a group of JobCardOp models from the database I want to add another field on the end; 'PreviousOpStatus'.
I know ill need something like;
$Ops = JobCardOp::where('JobCardNum', '=', $someJobNum)
->join('JobCardOps as JobCardOps_1, some constraint)
->select('JobCardOps.*', 'JobCardOps_1.OpStatus as PreviousOpStatus')
->get();
Where JobCardOps_1 is somehow offset by 1 if that makes sense. Can anyone help if this can be done?
Thanks
Related
Below is my code.
DB Code
return $this->model
->select('orderNumber','orderNumber as order_id','orderDate as order_date','status')
->where('orderNumber','=',$id)
->with(array('OrderDetail'=>function($query){
$query->select('productCode','orderNumber','priceEach as unit_price',DB::raw('quantityOrdered*priceEach as line_total'));
}))
->with('customer')
->first()->makeHidden(['orderNumber']);
I want to get the sum of the line_total column and it should be displayed under the order section as in the below image..
JSON Payload
DB Table Design
DB Table Design
I tried many ways, but could not achieve the expected outcome.
So your help is really appreciated.. :)
What you can do is you can add a select in main query like this:
->addSelect(['order_total' => DB::table('order_items')->whereRaw('order_items.order_id = orders.id')->sum('priceEach')]);
I hope this helps, let me know if you need something else.
I have three tables.
Radar data table (with id as primary), also has two columns of violation_file_id, and violation_speed_id.
Violation_speed table (with id as primary)
violation_file table (with id as primary)
I want to select all radar data, limited by 1000, from some start interval to an end interval, joins with violation_speed table. Each radar data must have a violation_speed_id.
I want to then join with the violation_file table, but not each radar records corresponding to violation_file_id, some records just has violation_file_id of 0, means there's no curresponding file.
My current sql is like this,
$results = DB::table('radar_data')
->join('violation_speed', 'radar_data.violation_speed_id', '=', 'violation_speed.id')
->leftjoin('violation_video_file', 'radar_data.violation_video_file_id', '=', 'violation_video_file.id')
->select('radar_data.id as radar_id',
'radar_data.violation_video_file_id',
'radar_data.violation_speed_id',
'radar_data.speed',
'radar_data.unit',
'radar_data.violate',
'radar_data.created_at',
'violation_speed.violation_speed',
'violation_speed.unit as violation_unit',
'violation_video_file.video_saved',
'violation_video_file.video_deleted',
'violation_video_file.video_uploaded',
'violation_video_file.path',
'violation_video_file.video_name')
->where('radar_data.violate', '=', '1')
->orderBy('radar_data.id', 'desc')
->offset($from_id)
->take($max_length)
->get();
It is PHP Laravel. But I think the translation to mysql statement is straight away.
My question is, is it a good way to select data like this? I tried but it seems a bit slow if the radar data grows to a large value.
Thanks.
Assuming you have the proper indices set this is largely the way to go, the only thing that's not 100% clear to me is what the offset() method does, but if it simply adds a WHERE clause than this should give you pretty much the best performance you're going to get. If not, replace it with a where('radar_data.id', '>', $from_id)
The most important indices are the ones on the foreign keys and primary keys here. And make sure not to forget the violate index.
The speed of the query often relies on the use of proper indexing on the joining clause and where clause used.
In your query there are 2 joins and if the joining keys are not indexed then you might need to apply the following
alter table radar_data add index violation_speed_id_idx(violation_speed_id);
alter table radar_data add index violation_video_file_id_idx(violation_video_file_id);
alter table radar_data add index violate_idx(violate);
The ids are primary key hence they are already indexed and should be covered
Using Laravel 4.2 & MySQL.
I have an applications table with an id and a fit_score_id column, and a fit_scores table with an id column. It's a basic "belongs to" relationship.
The following code:
$query = Application::join('fit_scores', 'applications.fit_score_id', '=', 'fit_scores.id');
$collection = $query->get();
...produces a collection of Application models with the id property set to the value of the fit_score_id. What am I doing to cause this?
I should note that it is necessary to do this join rather than simply using eloquent relations, because I'm going to want to order the results by a column on the fit_scores table. I don't believe this is possible using Eloquent without an explicit join.
The best way to solve this is by chaining the join method to a select method as following:
Application::select('*', \DB::raw("applications.id as appid"))
->join('fit_scores', 'applications.fit_score_id', '=', 'fit_scores.id')
->get();
Explained: The solution simply suggest that instead of thinking to prevent the behavior of overwriting the first id with the joined id, we can hook into the primary selection query (before joining) and change the label of the id column into something else (in this case 'appid'). By doing so, we end up with both the id of the parent table being labeled 'appid' and the id of the joined table being labeled 'id' again while they lives together on the final result.
I was able to find a possible solution using this answer:
Laravel 4 - JOIN - Same column name
Basically, since Laravel does not automatically prefix column names with table_name. for joined tables, we need to manually work around it by aliasing any conflicting column names in joins. Adding this select statement to my query did it:
->select(DB::raw("applications.*, fit_scores.*, applications.id as id"))
It depends on what you need but probably you can achieve it using eager loading. In case you need to mix joins and eager loading check this out. http://www.jmilan.net/posts/eager-loading-joins-in-laravel
I'm having trouble with Laravel syntax. I have a leftjoin as such:
$query=DB::table('jobs');
$query->leftjoin( 'attribute_int_data', 'attribute_int_data.job_id', '=', 'jobs.job_id' );
The problem is that where there is no record in the attribute_int_data table, I do not get the job_id from the jobs table.
I understand this may be because I have two column names that are the same, and I need to apply an alias to one of the column names to get the job_id.
Can anyone help with the syntax please?
Cheers.
Found the solution, hope it's of use to someone.
I added an array to the get, where I renamed the conflicting job_id column name.
$get_array = array(
'jobs.job_id as real_id',
...other values...
)
Then, to implement this, when I get the query:
$query->get($get_array);
And i get the job_id even when there are no matching records in the right table.
The situation is as follows: I've got 2 models: 'Action' and 'User'. These models refer to the tables 'actions' and 'users', respectively.
My action table contains a column user_id. At this moment, I need an overview of all actions, and the users to which they are assigned to. When i use $action->fetchAll(), I only have the user ID, so I want to be able to join the data from the user model, preferably without making a call to findDependentRowset().
I thought about creating custom fetchAll(), fetchRow() and find() methods in my model, but this would break default behaviour.
What is the best way to solve this issue? Any help would be greatly appreciated.
I designed and implemented the table-relationships feature in Zend Framework.
My first comment is that you wouldn't use findDependentRowset() anyway -- you'd use findParentRow() if the Action has a foreign key reference to User.
$actionTable = new Action();
$actionRowset = $actionTable->fetchAll();
foreach ($actionRowset as $actionRow) {
$userRow = $actionRow->findParentRow('User');
}
Edit: In the loop, you now have an $actionRow and a $userRow object. You can write changes back to the database through either object by changing object fields and calling save() on the object.
You can also use the Zend_Db_Table_Select class (which was implemented after I left the project) to retrieve a Rowset based on a join between Action and User.
$actionTable = new Action();
$actionQuery = $actionTable->select()
->setIntegrityCheck(false) // allows joins
->from($actionTable)
->join('user', 'user.id = action.user_id');
$joinedRowset = $actionTable->fetchAll($actionQuery);
foreach ($joinedRowset as $joinedRow) {
print_r($joinedRow->toArray());
}
Note that such a Rowset based on a join query is read-only. You cannot set field values in the Row objects and call save() to post changes back to the database.
Edit: There is no way to make an arbitrary joined result set writable. Consider a simple example based on the joined result set above:
action_id action_type user_id user_name
1 Buy 1 Bill
2 Sell 1 Bill
3 Buy 2 Aron
4 Sell 2 Aron
Next for the row with action_id=1, I change one of the fields that came from the User object:
$joinedRow->user_name = 'William';
$joinedRow->save();
Questions: when I view the next row with action_id=2, should I see 'Bill' or 'William'? If 'William', does this mean that saving row 1 has to automatically update 'Bill' to 'William' in all other rows in this result set? Or does it mean that save() automatically re-runs the SQL query to get a refreshed result set from the database? What if the query is time-consuming?
Also consider the object-oriented design. Each Row is a separate object. Is it appropriate that calling save() on one object has the side effect of changing values in a separate object (even if they are part of the same collection of objects)? That seems like a form of Content Coupling to me.
The example above is a relatively simple query, but much more complex queries are also permitted. Zend_Db cannot analyze queries with the intention to tell writable results from read-only results. That's also why MySQL views are not updateable.
You could always make a view in your database that does the join for you.
CREATE OR REPLACE VIEW VwAction AS
SELECT [columns]
FROM action
LEFT JOIN user
ON user.id = action.user_id
Then just use
$vwAction->fetchAll();
Just remember that views in MySQL are read-only (assuming this is MySQL)
isn't creating a view sql table a good solution to make joint ?
and after a simple table class to access it
I would think it's better if your logic is in sql than in php