Thanks it worked!
*models.py*
class Experiments(db.Model):
id = db.Column(db.Integer, primary_key=True)
kountry = db.Column(db.String(100))
#countryland = db.Column(db.String(100))
*migration file*
from alembic import op
import sqlalchemy as sa
from sqlalchemy.dialects import mysql
def upgrade():
# ### commands auto generated by Alembic - please adjust! ###
# op.add_column('experiments', sa.Column('kountry',
sa.String(length=100), nullable=True))
# op.drop_column('experiments', 'countryland')
op.alter_column('experiments',
column_name = 'countryland',
new_column_name = 'kountry',
existing_type = sa.String(100),
existing_nullable = False,
existing_server_default = 'Greenland')
# ### end Alembic commands ###
Electronically yours,
Mike
On Tuesday, August 27, 2019 at 12:15:06 PM UTC+2, Mike wrote:
>
> *Setup:*
> mysql> SELECT version();
>
> * 5.7.27-0ubuntu0.18.04.1
> * Python 3.6.8
> * SQLAlchemy 1.3.6
> * Alembic 1.0.11
>
>
> *models.py:*
> class Experiments(db.Model):
> id = db.Column(db.Integer, primary_key=True)
> # country = db.Column(db.String(100))
> countryland = db.Column(db.String(100))
>
> insert_date = db.Column(db.DateTime, index=True,
> default=datetime.utcnow)
>
>
> *SQL data:*
> INSERT INTO experiments (country)
> VALUES ('US'),
> ('Canada'),
> ('Mexico'),
> ('Brazil'),
> ('Argentina'),
> ('Spain'),
> ('Portugal'),
> ('France'),
> ('Germany'),
> ('UK');
>
>
> *migration file:*
> def upgrade():
> # ### commands auto generated by Alembic - please adjust! ###
>
> # op.add_column('experiments', sa.Column('countryland',
> sa.String(length=100), nullable=True))
> # op.drop_column('experiments', 'country')
>
> op.alter_column('experiments', column_name='country',
> new_column_name='countryland')
>
> # ### end Alembic commands ###
>
>
>
> *Problem:*
> I want to rename the column name from *"country"* to *"countryland"*. But
> I'm getting this error in my terminal can anybody help me please?
>
> $ flask db upgrade
>
> [2019-08-27 11:43:26,155] INFO in __init__: microblog startup
> INFO [alembic.runtime.migration] Context impl MySQLImpl.
> INFO [alembic.runtime.migration] Will assume non-transactional DDL.
> INFO [alembic.runtime.migration] Running upgrade 1f866a4fa5a0 ->
> 69e7cfcf87f1, Testing column rename 02.
> ERROR [root] Error: All MySQL CHANGE/MODIFY COLUMN operations require the
> existing type.
>
>
> Electronically yours,
> Mike
>
>
--
You received this message because you are subscribed to the Google Groups
"sqlalchemy-alembic" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sqlalchemy-alembic+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/sqlalchemy-alembic/01adb38a-0ec5-403b-9825-b1511f41a429%40googlegroups.com.
