By the sounds of it, you are more interested in sequentially listed revision files rather than sequentially ordered revision ids. The former can be achieved without any change to how the revision ids are generated. The alembic.ini file that is generated when you run alembic init alembic has a section that configures the naming of … Read more
To rename a column as of Alembic 0.9.5 I had to alter my migration to read as follows: op.alter_column(‘my_table’, ‘old_col_name’, nullable=False, new_column_name=”new_col_name”)
As per @zzzeek, after I included the following in my env.py, I was able to work with –autogenerate option in env.py under run_migrations_online() from configuration import app from core.expense.models import user # added my model here alembic_config = config.get_section(config.config_ini_section) alembic_config[‘sqlalchemy.url’] = app.config[‘SQLALCHEMY_DATABASE_URI’] engine = engine_from_config( alembic_config, prefix=’sqlalchemy.’, poolclass=pool.NullPool) then I ran alembic revision –autogenerate -m … Read more
Since version 0.8.8, alembic supports PostgreSQL’s USING with the postgresql_using parameter: op.alter_column(‘views’, ‘cols’, type_=postgresql.BIT(varying=True), postgresql_using=’col_name::expr’)
I’ve solved the problem by setting sqlalchemy.url in env.py as @dirn suggested. config.set_main_option(‘sqlalchemy.url’, <db_uri>) did the trick, where <db_uri> can be loaded from environment or config file.
You need to get the connection object, call execute() on it and pass query parameters as keyword arguments: from alembic import op from sqlalchemy.sql import text conn = op.get_bind() conn.execute( text( “”” insert into field_tags (id, field_id, code, description) values (1, ‘zasz’, :code , :description) “”” ), **t ) Also see: How to execute raw … Read more
Here’s how to produce an error like that: >>> from sqlalchemy import * >>> create_engine(“driver://”) Traceback (most recent call last): … etc sqlalchemy.exc.ArgumentError: Can’t load plugin: sqlalchemy.dialects:driver so I’d say you aren’t actually using the postgresql URL you think you are – you probably are calling upon a default-generated alembic.ini somewhere.
Perhaps the most conventional (and robust) solution is to use alembic merge heads. In the same way that when you have two branches in Git you can bring them back together with a merge commit, in Alembic when you have two branches you can bring them back together with a merge revision. For instance, suppose … Read more
Alembic has, as one of its operation, bulk_insert(). The documentation gives the following example (with some fixes I’ve included): from datetime import date from sqlalchemy.sql import table, column from sqlalchemy import String, Integer, Date from alembic import op # Create an ad-hoc table to use for the insert statement. accounts_table = table(‘account’, column(‘id’, Integer), column(‘name’, … Read more
Alembic stores the version history in your database. Hence it is using the value stored in your database to search for the revision. The version number for my personal database is stored in the table alembic_version: mysql> SELECT * FROM alembic_version; +————-+ | version_num | +————-+ | c8ad125e063 | +————-+ 1 row in set (0.00 … Read more