I'm currently building a Laravel 5.7 app where I have multiple boolean columns that indicate if some facilities are available for a building (model), eg, toilet yes/no. This works fine, but I was wondering what happens when I add more of these boolean columns later when I deploy the app.
Say I add a boolean column 'lights,' I could give it a default value of 0, but not NULL. So now all my existing buildings will say that there are no 'lights' (because the value is 0), where in reality it should be something like 'don't know' or 'undefined' Like a third state.
Should I use ENUM columns with yes/no/undefined instead? What are best practices for this scenario?
What I would do, is create separate table, with object_id, and facility_id. Now, you can have dynamic facilites table, and connect them with object. Connection will only have what it needs, so not every object "light" or something else.
You can certainly create them them as nullable()! It is a common practice, IMO.
As far as best practices go, it depends on how your application should be used. Do you want a user to notice that the state has not been selected one way or the other yet? Maybe you are displaying a prompt to configure the ones that are null. On the other hand, it may be safer to assume that the options should default to false in order to be rendered properly. If this is the case, maybe a notification can go out to your users to update this property.
This worked to me
$table->boolean('lights')->nullable();
Yes Yo are Right this could be a problem some times
But the Boolean CAN BE USED SUCH AS TRUE (OR) FALSE ie) 0 (OR) 1
where in reality it should be something like 'don't know' or 'undefined' Like a third state.
So in this Situation use Can use Enum
For Example Your table will have ups_availablity
Scenario One :
If you want to add NotAvailable by default just pass the value inside default method
$table->enum('ups_availablity', ['Available', 'NotAvailable'])->default('NotAvailable');
Scenario Two:
If you want to add Null add nullable method
$table->enum('ups_availablity', ['Available', 'NotAvailable'])->nullable();
If You have any clarification Kindly Comment Below
Hope its helps
Related
I am working with some coaching using Redis in Nodejs.
here is my code implimentation.
redis.get(key)
if(!key) {
redis.set(key, {"SomeValue": "SomeValue", "SomeAnohterValue":"SomeAnohterValue"}
}
return redis.get(key)
Till here everything works well.
But let's assume a situation where I need to get the value from a function call and set it to Redis and then I keep getting the same value from Redis whenever I want, in this case, I don't need to call the function again and again for getting the value.
But for an instance, the values have been changed or some more values have been added to my actual API call, now I need to call that function again to update the values again inside the Redis corresponding to that same key.
But I don't know how can I do this.
Any help would be appreciated.
Thank you in advanced.
First thing is that your initial code has a bug. You should use the set if not exist functionality that redis provides natively instead of doing check and set calls
What you are describing is called cache invalidation and is one of the hardest parts in software development
You need to do a 'notify' in some way when the value changes so that the fetchers know that it is time to grab the most up to date value.
One simple way would be to have a dirty boolean variable that is set to true when the value is updated and when fetching you check that variable. If dirty then get from redis and set to false else return the vue from prior
My bot asks: 'how do you (i.e. customer) want to pay for this product?'
Customer says: 'part in cash and the difference in 48x'
What the customer is saying above is that he wants to pay in cash and use financing. And that financing should consider 48 installments.
Entities:
paymentType: {cash, financed} ; Financed includes 48x as a synonym
numInstallments: {12x, 24x, 36x, 48x} ; 48x is the number of installments desired
Using the GUI only, how to do this:
IF user says '48x' THEN simultaneously add 'financed' to the paymentType list AND set numInstallments equal to '48x' ?
Apparently the GUI doesn't allow me to do that unless I'm doing something wrong (see below the screen which allows a parameter to be mapped to an entity and notice that this dropdown apparently allows selection of a single entity and not two, which is what I need).
How to solve this problem in an easy way through the GUI?
I don't know if what you have in mind is actually feasible in this case.
What you could do is keep the intent and entities as-is and then create several conditions in the page where you fill this parameters or another page (i think this is preferred).
In that page you can put different routes where your conditions are true that modify your parameters as you wish.
For example, after asking the user how they'd like to pay, you can have a route going to a "Set parameters" page which has several routes:
First route has a condition $session.params.numeroDeParcelas != null (you know the user has asked a specific number of installments, so handle the case by setting the parameters you need in this route (under parameters in the route write paymentType : "financed")
Second route has another condition, for example $session.params.numeroDeParcelas = null (you know the user hasn't asked for financing, so set the same parameter as before to "cash")
and so on, until you've exhausted your user cases (all payment methods, possibly all types of financing).
Pay attention: the routes are always evaluated in order so make sure to keep this in mind while writing/ordering them: be specific to avoid fulfilling the wrong one by mistake (e.g. by creating compound conditions, chaining parameter checks as in $session.params.numeroDeParcelas = null AND $session.params. numInstallments = "36x"
I currently have a validation rule that prevents user from making changes to a record when its status is completed. Users are only allowed to make changes if the status is either draft or registered.
AND(
TEXT(Current_Status__c) <> "Draft",
TEXT(Current_Status__c) <> "Registered"
)
There is a new requirement to allow user to update only a specific picklist value field even if the record status is completed. If i remove the validation rule, user will be able to change any fields on the page layout which won't work.
Object setting for the profile is read, create, edit. This object is a child object to Opportunity, OWD is controlled by parent.
Any recommendation on how to solve this issue ?
Thanks in advance.
We can rewrite your rule as ISPICKVAL(Current_Status__c, 'Completed') for example, looks bit cleaner. Your call though, you can keep as is.
So what you'd need is something like ISPICKVAL(Current_Status__c, 'Completed') && !ISCHANGED(Some_Picklist__c). It should let the edit through if you're modifying that picklist.
The problem is it won't check if that's the only change. Usercan cheat, modify 10 fields and they'll "piggyback" and save OK as long as one of them is that picklist.
It's pain to write validation like ISPICKVAL(Current_Status__c, 'Completed') && !ISCHANGED(Some_Picklist__c) && (ISCHANGED(Field1__c) || ISCHANGED(Field2__c) || ISCHANGED(Field3__c)). You'd have to add all editable fields to it, change it every time you make new one. And eventually you'll hit length limits.
I know 3 options for this if it's a concern for you:
Ask a developer to rewrite your logic to Apex trigger, it could then go dynamic through all fields (using "describe" calls to learn field names or stuff like getPopulatedFieldsAsMap.
Another trick is to allow editing completed records only through a quick action, not normal edit page. In that action you could set some hidden checkbox in the field prepopulating step and your validation would let the save through only if that checkbox is set. But then you need to deactivate it somehow anyway or the bypass will get permamently enabled.
If you don't have too many record types on the object a common trick is to change the record type on completion (workflow, process builder etc). And have another page layout with all fields locked down except that special picklist. It works good enough for UI changes but won't protect if you have code and integrations writing to the object too.
I add a virtual column, then I filter it using "having". When I need to filter by one value, all works fine, but I also need to filter by "not null". having expects only 3 arguments, including the clause, the value and the binding type, is there any way to pass in a criteria?
$Sharings->having("TotalSharing = ?",2, \PDO::PARAM_INT);
Or do I have to add a new virtual column who has as value what I need directly?
Thanks a lot in advance!
Gioia
Ok, was actually a lot easier then I thought, I just used:
$Sharings->having("TotalSharing > ?",0, \PDO::PARAM_INT);
So I didn't need to use a Criteria object, silly of me not to think about this, just so used to use filterBy...
I am trying to read through the dataBind documentation, but it's not all that clear:
http://grails.org/doc/2.1.0/ref/Controllers/bindData.html
I have a composite id composed of 4 columns, and I need to update one of those. It refuses to .save() and doesn't even throw an error. Is there some configuration that will allow me to change these values and save the model?
If I delete it and create a new record, it will bump the rowid, which I was using on the browser side with datatables/jeditable, and it's not really an option. However, even if I include all the parameters with an empty list:
def a = WaiverExemption.find("from WaiverExemption as e where e.exemptionRowId = ?", [params.rowid])
a.properties = params
bindData(a, params, [include: []])
a.save(flush: true, failOnError: true)
This does not seem to work. I've also tried naming the columns/properties explicitly both by themselves and also with "id".
I was confused on what bindData() actually does. Still confused on that.
If you have a composite id in Grails and wish to change one or more of the column values, save() will never ever execute as suggested in the question. Instead, you'll want to use .executeUpdate(). You can pass in HQL that updates (though most of the examples on the web are for delete) the table in question, with syntax that is nearly identical to proper SQL. Something along the lines of "update domain d set d.propertyName = ?" should work.
I do not know if this is a wise thing to do, or if it violates some philosophical rule of how a Grails app should work, but it will actually do the update. I advise caution and plenty of testing. This crap's all voodoo to me.