creating database with REAL array column

[crabiner]

I have a database created using
CREATE TABLE "TestRealArray" ( "id" INTEGER PRIMARY KEY AUTOINCREMENT, "real_array" REAL[] NOT NULL )
I can view the database using "DB Browser for SQLite" and the type of the column is shown as REAL []
how can I create such a columnt using sqlite_orm?

[fnc12]

not sure that you can but type is actually isn't important in SQLite. You can insert any type of data in real_array column actually: blob, null, int, double, text. Type is affinity not a rule in SQLite.

[crabiner]

Thanks for the answer!
How would I save an array of floats in sqlite_orm?

[fnc12]

it depends on how you want to do it in raw SQLite. There is plenty of ways of doing it. How would you do it in raw SQLite?

[crabiner]

I'm using pony ORM in python to create db containing for example a column called "rotation" holding a vector with the following data
[-2.244766578150064e-32,-4.1646004162569874e-33,-0.7071067811865474,0.7071067811865477]
I need to read this on sqlite_orm c++ and also be able to write a similar table using the sqlite_orm c++ that can be read by pony ORM python

[fnc12]

you need to understand how pony ORM inserts rotation vector and implement the same way of extracting data. Good news: sqlite_orm allows you implementing any type of serialization/deserialization for custom type and you can inspect it in examples folder. E.g. https://github.com/fnc12/sqlite_orm/blob/master/examples/nullable_enum_binding.cpp, https://github.com/fnc12/sqlite_orm/blob/master/examples/enum_binding.cpp. If you have any questions please feel free to ask

[crabiner]

Big like on the custom type feature
I'm taking that as home work to try to implement the string above to a new custom type of float array

Would you recommend the custom type struct to be

struct FloatArray{
    std::vector<float> farray;
};

?

[fnc12]

why not. It is the easiest way of doing it. Your main goal here is to understand how data is serialized by pony ORM and make symmetric deserialization of FloatArray

[crabiner]

Amazing!
I ended up supporting std::vector directly
by implementing the functions below

and I was even able to load a database created by sqlite_orm c++ into another orm called pony in python
I will open a new question I have in another issue about reading a pony orm database in sqlite_orm

    template<>
    struct type_printer<std::vector<float> > : public text_printer;

template<>
    struct statement_binder<std::vector<float> >

    template<>
    struct field_printer<std::vector<float> >;

    template<>
    struct row_extractor<std::vector<float> >

[fnc12]

@crabiner ok good for you. Can we close this issue?

[crabiner]

Yes thanks!