Model stored/encoded as a delimited string in the database?

[kennedy]

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Example Code

ActualData(BaseModel):
    id: int
    KnownName: str
    NickName: str
    Mother: str
    Father: str
    SocialSecurity: int
    Pets: Optional[boolean]
    Vegan: Optional[boolean]

Database Schema:
    id: int
    name: str # KnownName
    details: str # f"KnownName={KnownName};NickName={NickName};Mother={Mother};Father={Father};SocialSecurity={SocialSecurity};Pets={Pets};Vegan={Vegan}"

### Description

I have a very strange constraint, I am using SQLModel as my orm. I have a database with two important fields, for example `name` and `details`. The important information I need for my model `ActualData` is built from the `details` column from the database. 

How do I use the `ActualData` model in my code, but when I submit/save/read from the database, it is encoded as a character delimited string structure? 

[pydantic/validators](https://pydantic-docs.helpmanual.io/usage/validators/) was very helpful but it fills one field. Is it possible to fill out the entire model with one validator? How does one encode the model back to a single string within the database?

### Operating System

Windows

### Operating System Details

- win11 pro, python from windows store, pipenv

### SQLModel Version

0.0.8

### Python Version

3.10.8

### Additional Context

Think of [storing the string components of postgresql database connection string](https://www.connectionstrings.com/postgresql/), but storing it as a completed connection string

`User ID=root;Password=myPassword;Host=localhost;Port=5432;Database=myDataBase;Pooling=true;Min Pool Size=0;Max Pool Size=100;Connection Lifetime=0;`

[meirdev]

I recommend you use a JSON column for details. anyway, you have to create a new type:

from sqlalchemy.types import TypeDecorator, String

class ActualDataType(TypeDecorator):
    impl = String

    def process_bind_param(self, value, dialect):
        if value is not None:
            value = ";".join(f"{k}={v}" for k, v in value.dict().items() if v is not None)
        return value

    def process_result_value(self, value, dialect):
        if value is not None:
            d = {}
            for value in value.split(";"):
                k, v = value.split("=")
                d[k] = v
            value = ActualData(**d)
        return value

for JSON:

from sqlalchemy.types import TypeDecorato, JSON

class ActualDataType(TypeDecorator):
    impl = JSON

    def process_bind_param(self, value, dialect):
        if value is not None:
            value = value.dict()
        return value

    def process_result_value(self, value, dialect):
        if value is not None:
            value = ActualData(**value)
        return value

And finally, change the column type to be ActualDataType:

from sqlalchemy import Column

class Data(SQLModel, table=True):
    ...
    details: ActualData = Field(sa_column=Column(ActualDataType))

[kennedy]

@meirdev you are amazing, thank you for your suggestion. I will try this out and report back.