yeah~ it's work. thks. 在 2018年9月7日星期五 UTC+8上午1:48:46，Mike Bayer写道： > > for ALTER, which is not what you illustrated earlier, server default > comparison is turned off by default as it can be unreliable in some > cases. Turn it on using compare_server_default=True: > > http://alembic.zzzcomputing.com/en/latest/api/runtime.html#alembic.runtime.environment.EnvironmentContext.configure.params.compare_server_default > > > > > On Thu, Sep 6, 2018 at 12:37 PM, Yingchen Zhang <cevin....@gmail.com > <javascript:>> wrote: > > like this: > > > > old model: > > > > class TestModel: > > > > ip = db.Column(db.INET, nullable=False) > > > > > > new Model: > > > > class TestModel: > > > > ip = db.Column(db.VARCHAR(), nullable=False, > server_default='127.0.0.1') > > > > > > got migration: > > > > op.alter_column('test', 'ip', > > existing_type=postgresql.INET(), > > type_=sa.VARCHAR(), > > nullable=False) > > > > > > no default set. > > > > > > 在 2018年9月6日星期四 UTC+8下午9:54:23，Mike Bayer写道： > >> > >> On Thu, Sep 6, 2018 at 3:50 AM, Yingchen Zhang <cevin....@gmail.com> > >> wrote: > >> > so, alembic not support `default` ( pgsql create columnn ) ? > >> > >> it does. use server_default. "default" in SQLAlchemy refers to a > >> Python-side default. > >> > >> > >> > > >> > 在 2018年9月6日星期四 UTC+8上午12:24:54，Mike Bayer写道： > >> >> > >> >> On Wed, Sep 5, 2018 at 11:51 AM, Yingchen Zhang <cevin....@gmail.com> > > >> >> wrote: > >> >> > db.Column('text_column', db.VARCHAR(20), default='test_text', > >> >> > server_default='test_text', nullable=True) > >> >> > > >> >> > but, generated code like: > >> >> > > >> >> > sa.Column('text_column', sa.VARCHAR(20), nullable=True), > >> >> > >> >> I assume you are using Alembic autogeneration. The Python-side > >> >> default "test_text" is not needed in an alembic autogeneration. The > >> >> server_default however will be rendered. > >> >> > >> >> > >> >> I ran your column as given: > >> >> > >> >> target_metadata = MetaData() > >> >> > >> >> Table( > >> >> 't', target_metadata, > >> >> Column('text_column', VARCHAR(20), default='test_text', > >> >> server_default='test_text', nullable=True) > >> >> ) > >> >> > >> >> alembic generates: > >> >> > >> >> def upgrade(): > >> >> # ### commands auto generated by Alembic - please adjust! ### > >> >> op.create_table('t', > >> >> sa.Column('text_column', sa.VARCHAR(length=20), > >> >> server_default='test_text', nullable=True) > >> >> ) > >> >> # ### end Alembic commands ### > >> >> > >> >> > >> >> > >> >> > > >> >> > > >> >> > how to set column default value ? > >> >> > > >> >> > -- > >> >> > 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+...@googlegroups.com. > >> >> > To post to this group, send email to sqlal...@googlegroups.com. > >> >> > Visit this group at https://groups.google.com/group/sqlalchemy. > >> >> > For more options, visit https://groups.google.com/d/optout. > >> > > >> > -- > >> > 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+...@googlegroups.com. > >> > To post to this group, send email to sqlal...@googlegroups.com. > >> > Visit this group at https://groups.google.com/group/sqlalchemy. > >> > For more options, visit https://groups.google.com/d/optout. > > > > -- > > 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+...@googlegroups.com <javascript:>. > > To post to this group, send email to sqlal...@googlegroups.com > <javascript:>. > > Visit this group at https://groups.google.com/group/sqlalchemy. > > For more options, visit https://groups.google.com/d/optout. >
-- 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 post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
