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Woohoo! Hello!

Welcome :)

Здрасте

Hello

Heya! ^^

Heya! ^^

Yo ^^

:O

Hi :D

Hello, welcome!

thanks :D

god it took me too long to find this grup

Its just here -since a week or such

oh

So where did you run into?

ah yes

well i usually have stupid questions ?

now, what i'm looking for is to know if it has any sense to have a property in my class that is a Set(str)

No question is stupid ?

What's the problem you're running in to, to use that as a solution? :)

i just need that my "class" to have a list of strings

Hi everybody! @Rozzen, what database do you use?

sqlite3

Right now Set attributes can be used only with entity types, but in the distant future we can add support of Set(str) as well. At this moment you can store array of strings inside Json attribute: class MyEntity(dn.Entity): name = Required(str) tags = Optional(Json) ... x = MyEntity(name='foo') x.tags = ['one', 'two', 'three']

:O

that should be fine i guess

thanks :D

We support Json attribute in all databases (SQLite, MySQL, PostgreSQL, Oracle). To get best performance with SQLite you should compile it with json1 extension, but Json will work without that extension too, just a bit slower.

mmm what do you mean with "compile with json1 extension"? ?

As I understand it, SQLite does not include Json1 extension by default, and you need somehow enable it: https://www.sqlite.org/json1.html https://www.sqlite.org/loadext.html

ooh

It is not necessary, you can use PonyORM Json type without json1 extension.

i get it, but i love to learn those things

https://docs.ponyorm.com/json.html

As I understand it, SQLite does not include Json1 extension by default, and you need somehow enable it: https://www.sqlite.org/json1.html https://www.sqlite.org/loadext.html

damn i don't get it

it's mandatory to use C?

As I understand, yes. Actually, I have no experience with compiling that stuff myself. Maybe someone can explain better. There is an blog post of Charles Leifer in which he describes how to build SQLite with json1: http://charlesleifer.com/blog/using-the-sqlite-json1-and-fts5-extensions-with-python/

if you don't care about performance at this point, you don't need the JSON1 extension

if you don't care about performance at this point, you don't need the JSON1 extension

yes yes i got it, but i'd like to understand how to get more optimization in the future

I think it would be more convenient if future versions of SQLite include json1 by default

check out this article http://charlesleifer.com/blog/using-the-sqlite-json1-and-fts5-extensions-with-python/

so currently you can just use SQLite as is and once you'll see that you need better perfomance with JSON, you can think about compiling it with JSON1 module

so currently you can just use SQLite as is and once you'll see that you need better perfomance with JSON, you can think about compiling it with JSON1 module

i'll do that

but at least i know what to read when that happens

stupid question number two!

to set an image as a property?

usually it is a str - because you probably will keep an image url in this property

You can also store an image as a BLOB data inside the database (use buffer type for that), but usually it is much better to save images outside of the database and store the filename in a textual column.

silly question number 35! (?)

let's say i have a class Human(db.Entity): that has the propery pet = Required(Animal)

and i have the class Dog(Animal)

and i have a variable is a dog

so... i want to do something like a select(h for h in Human if h.pet == dog)

but dog isn't an animal, it's a dog, a child class of animal

and python implotes when i try to do that

sorry my english isn't tha best

I think it should work. Maybe the error is caused by some other reason. Can you provide a traceback with the error message?

grr i just fixed using ids

when i have time again i'll try and if it fails

i'll send the error message

now i got the error

<class 'pony.orm.sqltranslation.IncomparableTypesError'> ("Incomparable types 'Animal' and 'Set of Dog' in expression: h.pet == dog",)

aah

because i have like

class Dog(Animal): humans = Set("Human")

h in dog.humans

h in dog.humans

should be this way?

ok i changed to that and now i get

<class 'TypeError'> ("Expression dog.humans has unsupported type 'Set'",)

Can you show how you got the value of the dog variable

It seems that it is not a dog, but a set of dogs

i have a one to one relationship with some id that isn't the primary key

dog= Dog.get(oexr_id = id)

Can you paste the definitions of Animal, Dog and Human classes?

yep gimme a sec

pastebin or right here?

any way

class Animal(db.Entity): id_animal =PrimaryKey(int,size=64,auto=True) humans =Set("Human") classtype = Discriminator(str) _discriminator_="Animal" oexr =Required(OnlyExr) class Human(db.Entity): user =Required(User) pet =Required(Animal) classtype = Discriminator(str) _discriminator_="Human" class OnlyExr(db.Entity): id_exr =PrimaryKey(int,size=64) animals =Set("Animal") name =Required(str) class Dog(Animal): race =Optional(String) _discriminator_="Dog"

It looks strange that in your schema a human can has only one (required!) pet, while a pet belongs to many humans. I think it should be the other way

class Animal(db.Entity): ... owner = Required(Human) class Human(db.Entity): ... pets = Set(Animal)

And than you can find a dog by primary key: dog = Dog[dog_id] And find an owner of this dog: owner = dog.owner

Yeah i know xD

But i have like. Its a town with dogs that "have" many homes

And i want to get every person that have that dog as a pet

Like, those dogs choose where to eat, spend the time and sleep

Then probably the relation should be many-to-many (two Set attributes). But anyway, if any human of this city is required to have a dog, then select(h for h in Human if h.pet == dog) looks correct. But the error says that the value of a dog variable is not a single dog, but a set of dogs. You can print the variable and see its value.

hmmm ok

i get

Dog[3]

Then it is strange that the error says that you are comparing Animal with a Set of Dog. I don't see any Set here