sqlalchemy and auto increments with postgresql

Question

I created a table with a primary key and a sequence but via the debug ad later looking at the table design, the sequence isn\'t applied, just created.

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Answer 1

You specified an explicit Sequence() object with name. If you were to omit that, then SERIAL would be added to the id primary key specification:

CREATE TABLE tramos (
    id INTEGER SERIAL NOT NULL, 
    nombre VARCHAR, 
    tramo_data VARCHAR, 
    estado BOOLEAN, 
    PRIMARY KEY (id)
)

A DEFAULT is only generated if the column is not a primary key.

When inserting, SQLAlchemy will issue a select nextval(..) as needed to create a next value. See the PostgreSQL documentation for details.