Im working on a information-management system (vuejs, postgresql, graphql/hasura) for my company at the moment. We work project-based and have a lot of information to handle. Using postgresql, I've set up a few tables, ex client_information, general_information, internal_information and so on. (see structure below)
title -----| value | completed | date | project_number
-------------------------------------------------
customer -- walmart -- true ----- xx ----- 19823 --
contact --- xxxxxx --- false ---- xx ----- 19823 --
email ----- xxxxxx --- false ---- xx ----- 19823 --
So, this table with client_info contains info about all the clients we have, and each row is connected to a project by it's project number (19823). So, using hasura(graphQL) I make a request that returns all information about a chosen project in the form of a array filled with objects:
[ { title: 'customer', value: 'walmart', completed: true,
date: 'xx' project_number: 10823 }, {...}, {...}, {...} ]
So far all is fine and dandy, I could just v-for through the entire array and spit out all the information I need.
BUT, I'd like to be able to control in which order the items are displayed. During testing I created a function that takes in the array of objects above, and an array that I specify on the client looking like this:
['email', 'customer', 'contact']
This orders the array of items in the order specified, and works, but feels.. weird?
Consider this example:
This is my array:
const arr = [
{title: "customer", value: "walmart"},
{title: "email", value: "xx#xx.xx"},
{title: "phone", value: "01234"}
];
Then I do a:
<li v-for="item in arr">, text-field(vuetify) with placeholder="item.title", and v-model="item.value" </li>
That prints out the 3 items in the order of the array, so customer first, then email, then phone. What I don't understand is how to arrange the order of items. Maybe I want phone first, with a v-for loop, how is that possible? And yes, the array is way longer than just 3 items.
It might be that it's my first time using a relational database and my lack of experience is messing me up, but with the old database (firebase) everything was quite easy since each project was stored as a separate object. If I wanted the client email I'd just link a text-field to project.customer.email, and therefore had control. For reasons we need to move to postgresql and I'm not sure how to get the same control, maybe my solution is an "okay" one even though it feels a little weird to me, I dont know.
I was thinking about indexing the items in the db but I'd like to control if from the client in case we need to make layout-changes later on.
This turned into a novel, but if any of you guys have faced a similar situation and have some tips I'd greatly appreciate them.
Related
I have three tables, 'sessions', 'classes' and 'schedules' which they are connected each other.
sessions: id, name, descr
classes: id, session_id, name
schedules: class_id, session_id, date
A class belongs to a session, while the schedules is a N:M relations which gives the opportunity to have particular date for each session within a single class.
My problem comes when I have to display these information, I have a function which displays all Sessions:
$sessions = Session::all();
and I have another function which displays the date of a specific class and a specific session as below:
$result = Schedule:where('class_id','=',$classId)->where('session_id','=',$essionId)->first();
So let say I have 30 sessions for a single class, when it comes to my front-end app which is written in AngularJS I dont know how to handle the displaying here using the ng-repeat iterating thru all sessions and then make another call withing the ng-repeat iteration to call the schedule to display the date of the session, this is not a good practice I guess in AngularJS.
Could anyone tell me what would be the best option for me to handle this problem? Shall I have to modify the back-end? like edit the Session:all(); query to include also the Schedule table? or what is the best way?
I supposed you have already config your relations in models, if not look here
As for me, I use Fractal to customize display data. Also there is convenient method called Available includes
So you can request your data like /sessions/?include=classes and get output
{data: [{
session_id: 1,
some: "data",
classes:[{
class_id: 11,
some: "class_data"
}]
}]}
I would "eager load" the data, so you can access all the object's parents through the object you loaded. This way you can fill your table rows one by one by just iterating over 1 object.
There is excellent documentation about eager loading at the Laravel website, so I suggest you start there
I've been using NeDB as a persistent data storage model in my Electron/Angular application. The setup of this data works perfectly for the main purpose of my application. I show everything from table "0" and when the use clicks on an options it takes them to all items from table "1" that have a "foreign" that matches the "key" from the selected item from table "0". Like any other 1:n relational data.
I want to display the objects in an accordion like fashion for my users to be able to interact with the relationships. I want to be able to do this recursively, but cannot seem to wrap my head around it.
A chunk from my flat JSON file is this:
{"_id":"000000","type":"dc","table":"0","key":"A","cat":"CAD Assessment","foreign":"A"}
{"_id":"000002","type":"dc","table":"1","key":"1","cat":"Coronary angiography with or without left heart catheterization and left ventriculography","foreign":"A"}
{"_id":"000005","type":"dc","table":"2","key":"1.1","cat":"Suspected or known ACS","foreign":"1"}
{"_id":"000006","type":"dc","table":"2","key":"1.2","cat":"Suspected CAD: No prior noninvasive stress imaging (no prior PCI, CABG, or angiogram showing >=50% angiographic stenosis)","foreign":"1"}
And I want it to look like this:
{
"_id":"000000",
"type":"dc",
"table":"0",
"key":"A",
"cat":"CAD Assessment",
"foreign": [
{
"_id":"000002",
"type":"dc",
"table":"1",
"key":"1",
"cat":"Coronary angiography with or without left heart catheterization and left ventriculography"
"foreign": [
{
"_id":"000005",
"type":"dc",
"table":"2",
"key":"1.1",
"cat":"Suspected or known ACS",
"foreign":"1"
},
{
"_id":"000006",
"type":"dc",
"table":"2",
"key":"1.2",
"cat":"Suspected CAD: No prior noninvasive stress imaging (no prior PCI, CABG, or angiogram showing >=50% angiographic stenosis)",
"foreign":"1"
}
]
}
]
}
Is this even a possible thing? I'm hoping somebody with a lot more experience can point me in the right direction here. I'm ready to stop banging my head against the wall.
I am working to solve a problem not dissimilar to the discussion present at the following blog post. This is wishing to publish two related data sets in Meteor, with a 'reactive join' on the server side.
https://www.discovermeteor.com/blog/reactive-joins-in-meteor/
Unfortunately for me, however, the related collection I wish to join to, will not be joined using the "_id" field, but using another field. Normally in mongo and meteor I would create a 'filter' block where I could specify this query. However, as far as I can tell in the PWR package, there is an implicit assumption to join on '_id'.
If you review the example given on the 'publish-with-relations' github page (see below) you can see that both posts and comments are being joined to the Meteor.users '_id' field. But what if we needed to join to the Meteor.users 'address' field ?
https://github.com/svasva/meteor-publish-with-relations
In the short term I have specified my query 'upside down' (as luckily I m able to use the _id field when doing a reverse join), but I suspect this will result in an inefficient query as the datasets grow, so would rather be able to do a join in the direction planned.
The two collections we are joining can be thought of as like a conversation topic/header record, and a conversation message collection (i.e. one entry in the collection for each message in the conversation).
The conversation topic in my solution is using the _id field to join, the conversation messages have a "conversationKey" field to join with.
The following call works, but this is querying from the messages to the conversation, instead of vice versa, which would be more natural.
Meteor.publishWithRelations({
handle: this,
collection: conversationMessages,
filter: { "conversationKey" : requestedKey },
options : {sort: {msgTime: -1}},
mappings: [{
//reverse: true,
key: 'conversationKey',
collection: conversationTopics,
filter: { startTime: { $gt : (new Date().getTime() - aLongTimeAgo ) } },
options: {
sort: { createdAt: -1 }
},
}]
});
Can you do a join without an _id?
No, not with PWR. Joining with a foreign key which is the id in another table/collection is nearly always how relational data is queried. PWR is making that assumption to reduce the complexity of an already tricky implementation.
How can this publish be improved?
You don't actually need a reactive join here because one query does not depend on the result of another. It would if each conversation topic held an array of conversation message ids. Because both collections can be queried independently, you can return an array of cursors instead:
Meteor.publish('conversations', function(requestedKey) {
check(requestedKey, String);
var aLongTimeAgo = 864000000;
var filter = {startTime: {$gt: new Date().getTime() - aLongTimeAgo}};
return [
conversationMessages.find({conversationKey: requestedKey}),
conversationTopics.find(requestedKey, {filter: filter})
];
});
Notes
Sorting in your publish function isn't useful unless you are using a limit.
Be sure to use a forked version of PWR like this one which includes Tom's memory leak fix.
Instead of conversationKey I would call it conversationTopicId to be more clear.
I think this could be now much easier solved with the reactive-publish package (I am one of authors). You can make any query now inside an autorun and then use the results of that to publish the query you want to push to the client. I would write you an example code, but I do not really understand what exactly do you need. For example, you mention you would like to limit topics, but you do not explain why would they be limited if you are providing requestedKey which is an ID of a document anyway? So only one result is available?
I've seen other posts in this site regarding the same issue and I've tried the solutions given. I've also visited the links that may offer a solution but I'm still stuck with the same error.
I'm using DOJO and something as simple as this won't even work
myStore.newItem({id: 'test', otherfield: 'otherinfohere'});
myStore.save();
Supposedly the "newItem() was not passed an identity for the new item" error appears when you haven't provided an identifier for the new item, which i have.
The whole purpose of this (Just in case anyone can provide a good idea or has done something similar before) is that i want to create a data grid that shows info from a particular store. The problem is, that in that store all the items may not have the same structure. For instance:
I may have a store that looks like this
{identifier: 'id',
label: 'name',
items: [
{ id:'1', name:'Ecuador', capital:'Quito' },
{ id:'2', name:'Egypt', capital:'Cairo' },
{ id:'3', name:'El Salvador', capital:'San Salvador' , additionalField: 'otherinfohere'},
{ abbr:'gq', name:'Equatorial Guinea', capital:'Malabo', additionalField: 'otherinfohere'},
]}
This is possible because I'm the one constructing the store in a Spring Controller (I'm also using the Spring Framework) from information I have locally stored in a Berkeley DB. So what i need is a data grid with a dynamic layout because I don't want blank spaces to show in the view in the rows with lesser amount of fields, and i need to show all the info in the store at the same time, but i don't know how to do this.
I thought of doing it by creating a simple layout of only 1 field. In it I would load data from a store i create dynamically at runtime. The data in the store would be composed of HTML combined with the values coming from the original store so I could obtain something like this, which is inside an attribute of a JavaScript Object and let the browser parse it for me:
<div><span>id: originalID </span>....</div>
This of course is a simple example, the html layout i'm looking for is far more complicated, but i think that passing it as a string to an object might do the trick.
The problem is that i don't even know if that idea will work because i get that error whenever i try to add values to my secondary store.
rdb.modules.monitor.historicStore.fetch({onComplete: function(items, request){
for (var i = 0; i < items.length; i++){
var item = items[i];
var obj = new Object();
obj.id = rdb.modules.monitor.historicStore.getValue(item, "id");;
var html = "<div><span>";
html += rdb.modules.monitor.historicStore.getValue(item, "sql");
html += "</span></div>";
obj.html = html;
myStore.store.newItem(obj);
}
}});
In this context "historicStore" refers to the JSON store that has the values that i need to convert and add to "myStore" after i added some HTML.
I hope you got the main idea of what I'm trying to do. If anyone can help me we either of these problems i would really appreciate it. Thanks in advance
For the issue regarding store:-
"id" is mandatory for a store, if it is going to be used for a grid(datagrid, EnhancedGrid, etc. whatever). The items are handled only on basis of "id" attribute by the grid data structures.
Usually, id can be a loop variable/ auto incrementation, to avoid any cases like you have said. Before adding the store to the grid, ensure that all items have the id attribute. You can write a function which will loop through each item and check for this, else add an auto-incrementing value for the id attribute of that item.
I'm trying to get the backbone-relational plugin working with an association between tasks and messages. (A task has many messages).
The information is pulled from a standard rails/activerecord site, which has a task_id field as the foreign key.
The problem is, backbone-relational won't populate the 'messages' field with any messages on teh Task model unless I set the key as "task_id" in the reverse relation...but that means that, when accessing the task from the Message model, the task_id field is populated with the actual task object, not the 'task_id' integer, which is overwritten.
I'm guessing there's a simple way to specify task_id as the foreign key with which to determine the parent task, yet have the object that key represents placed in a different field (eg 'task' on the messages object)...but I can't figure out how. Any ideas appreciated. Code below
class Backbonescaffolddemo.Models.Task extends Backbone.RelationalModel
paramRoot: 'task'
relations: [{
type: Backbone.HasMany,
key: "messages",
relatedModel: "Backbonescaffolddemo.Models.Message",
collectionType: "Backbonescaffolddemo.Collections.MessagesCollection",
includeInJSON: true
reverseRelation: {
key: "task_id"
includeInJSON: true
}
}]
You may be able to use keySource or keyDestination to address your particular problem.
Example
In the following example, suppose we are getting data from an old-school relational database, where there is a one-to-many relationship between Monster and Loot_Item. This relationship is expressed by a Monster_Id foreign key in the Loot_Item table. Let us also suppose that our REST service doesn't do any fancy-pants data nesting for us, since that seems to match the situation in your question fairly closely.
keySource
Now, let's set set "keySource" to my foreign key ("Monster_Id") and "key" to the name of the attribute where I want the actual data to go (say, "Monster"). If you break in the debugger, you will see in the attributes object that there is, in fact, a field called "Monster", and that it does point to the monster model data. Hey, cool!
includeInJSON
However, if you toJSON that puppy, guess what? It has put all the monster data in Monster_Id, just like you didn't want! GAH! We can fix that by setting "includeInJSON" to "Monster_Id". Now, when it is converted to JSON, it puts the proper ID back into the Monster_Id field, when it is serializing your data to JSON, to send up to the server.
Problem solved? Er, well, actually, not necessarily...
CAVEAT: This all sounds super-useful, but there's one fairly glaring problem that I have found with this scenario. If you are using a templating engine (such as the one in Underscore.js) that requires you to convert your model to JSON, before passing it into the template, whoops -- you don't have access to your relational data. Alas, the JSON that we want for our messages is not necessarily the same JSON that we want to feed into our templates.
If you want the "task_id" in the message JSON to be the id, not the full JSON for the task, then set the "includeInJSON" to be the Task's ID property ("task_id")
class Backbonescaffolddemo.Models.Task extends Backbone.RelationalModel
paramRoot: 'task'
relations: [{
type: Backbone.HasMany,
key: "messages",
relatedModel: "Backbonescaffolddemo.Models.Message",
collectionType: "Backbonescaffolddemo.Collections.MessagesCollection",
includeInJSON: true
reverseRelation: {
key: "task_id"
includeInJSON: "task_id"
}
}]
The "true" value for includeInJSON says to use the full JSON for the related model.
Edit: After re-reading your question, I'm not sure my answer relates to your issue.
My original answer is for posting a message back to the server where you want the JSON to be something like:
{
"message_title": "My Title",
"message_body": "Blah blah blah...",
"task_id": 12345
}
I'm not sure what exactly you're looking to happen, but the way that Backbone Relational is supposed to work is that the Task's collection of messages will be a collection of the full models, so you can iterate over them and pass them to views for rendering, etc.
If you want to output one of the Message's id's in a template or something, then you'd take the Message model's "id":
myTask.get('messages').first().id -> returns the first message's id