Dear all, I am using: sqlalchemy==1.3.18 psycopg2==2.8.4 connection url schema: "postgresql+psycopg2://..." postgres 10.x
when I define an explicit AutomapBase-derived model for 'sqa_global_context' table with only the primary key, I expected that running `Base.metadata.reflect(bind=database.ENGINE, only=['sqa_global_context']); Base.prepare()` would backfill missing columns and relationships in that table. However, after running `Base.prepare(engine, reflect=True)`, the missing columns and relationships are not populated in my table. My code looks like this: ``` _AutomapBase = automap.automap_base() class SqaGlobalContext(_AutomapBase): """Type template for the SqaGlobalContext table.""" __tablename__ = 'sqa_global_context' key = sa.Column( sa.Integer, primary_key=True, server_default=sa.text('0')) _AutomapBase.metadata.reflect(bind=ENGINE, only=['ewf_sqa_global_context', <other related table names of interest>]) _AutomapBase.prepare() ``` The reason I use `_AutomapBase.metadata.reflect(ENGINE, only=[...])` followed by `_AutomapBase.prepare()` instead of just `_AutomapBase.prepare(ENGINE, reflect=True)` is because `_AutomapBase.prepare(ENGINE, reflect=True)` ends up reflecting **all** the tables in the database and I wanted to avoid the unnecessary overhead of reflecting the many additional tables that are managed by another subsystem not of interest to my application. So, after running the above code, I expected `SqaGlobalContext` model to be populated with additional columns (`created_at`, `updated_at`, etc.) and relationships based on foreign keys (see below for actual table DDL). But the missing columns and relationships didn't get added: ``` dir(SqaGlobalContext) ['__abstract__', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__mapper__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__table__', '__tablename__', '__weakref__', '_decl_class_registry', '_sa_class_manager', '_sa_decl_prepare', '_sa_raise_deferred_config', 'classes', 'key', 'metadata', 'prepare'] ``` As you can see from `dir(SqaGlobalContext)` - the additional columns didn't get populated in `SqaGlobalContext`. So, how can I make this work without reflecting the all the tables in the database? Alembic outputs this when generating this table: ``` INFO [sqlalchemy.engine.base.Engine] CREATE TABLE ewf_sqa_global_context ( key INTEGER DEFAULT 0 NOT NULL, created_at TIMESTAMP WITH TIME ZONE DEFAULT now() NOT NULL, updated_at TIMESTAMP WITH TIME ZONE DEFAULT now() NOT NULL, testing_suspended BOOLEAN DEFAULT false NOT NULL, metadata_tag VARCHAR(256) DEFAULT NULL, attempt_number INTEGER DEFAULT NULL, attempt_context_id INTEGER DEFAULT NULL, CONSTRAINT pk_ewf_sqa_global_context PRIMARY KEY (key), CONSTRAINT fk_ewf_sqa_global_context_metadata_tag_ewf_empower_metadata FOREIGN KEY(metadata_tag) REFERENCES ewf_empower_metadata (tag) ON DELETE RESTRICT ON UPDATE CASCADE, CONSTRAINT fk_ewf_sqa_global_context_attempt_context_id_ewf_sqa_at_0183 FOREIGN KEY(attempt_context_id) REFERENCES ewf_sqa_attempt_context (key) ON DELETE RESTRICT ON UPDATE CASCADE ``` Actual Schema in database. ``` CREATE TABLE public.ewf_sqa_global_context ( key integer NOT NULL DEFAULT 0, created_at timestamp with time zone NOT NULL DEFAULT now(), updated_at timestamp with time zone NOT NULL DEFAULT now(), testing_suspended boolean NOT NULL DEFAULT false, metadata_tag character varying(256) COLLATE pg_catalog."default" DEFAULT NULL::character varying, attempt_number integer, attempt_context_id integer, CONSTRAINT pk_ewf_sqa_global_context PRIMARY KEY (key), CONSTRAINT fk_ewf_sqa_global_context_attempt_context_id_ewf_sqa_at_0183 FOREIGN KEY (attempt_context_id) REFERENCES public.ewf_sqa_attempt_context (key) MATCH SIMPLE ON UPDATE CASCADE ON DELETE RESTRICT, CONSTRAINT fk_ewf_sqa_global_context_metadata_tag_ewf_empower_metadata FOREIGN KEY (metadata_tag) REFERENCES public.ewf_empower_metadata (tag) MATCH SIMPLE ON UPDATE CASCADE ON DELETE RESTRICT ``` -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/280b0e8e-99e7-4c53-af65-297ad1ed5ba4o%40googlegroups.com.