How to implement a composite primary key

[jaohbib]

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Example Code

class test(SQLModel, table=True):
     src_ppn: str = Field(primary_key=True)
     dst_ppn: str  = Field(primary_key=True)
   
     __table_args__ = (
         PrimaryKeyConstraint(src_ppn, dst_ppn),
     )

Description

I want to create a table containing a composite primary key
I recive the following error

ArgumentError: String column name or column expression for DDL constraint expected, got FieldInfo(annotation=NoneType, required=True).

Operating System

Linux

Operating System Details

Ubuntu 22.04

SQLModel Version

0.0.22

Python Version

3.9.7

Additional Context

No response

[monchin]

I guess there's something wrong with PrimaryKeyConstraint. You csn try to remove it like the example in the document

[acidnik]

in case someone landed here from the search engine, i think the problem could be fixed like this:

     __table_args__ = (
         PrimaryKeyConstraint("src_ppn", "dst_ppn"), # note the quotes around fields
     )