Why varchar(1) for boolean data types in tables like RELATIONSHIP?

Implementers
1

Hi, new user here and have searched for an answer to this and only found an old thread where the question posed wasn’t answered.

Tables like RELATIONSHIP in OMOP standard specify varchar(1) for fields containing TRUE or FALSE boolean flag like values. Is there a reason this was chosen over boolean data type or integer?

2

Purely historic reasons, @Prayag_Patil. The OMOP CDM is 18 years old.

1 Like