Float() parameters don't enforce proper database column definition with MySQL

[Former user]

I'm using flask-sqlalchemy and its developer said that the following is a SQLAlchemy issue:

If I do something like: lat = db.Column(db.Float(precision=16, scale=6), nullable=False)

and then I use MySQL's SHOW CREATE TABLE tablename .. I get the following: lat float NOT NULL,

Which shows that the precision and scale parameters are ineffective.

[Mike Bayer]

sorry, not a bug, use :

from sqlalchemy.dialects.mysql import FLOAT

[Mike Bayer]

the Float type should not be accepting and ignoring kwargs here.

[Mike Bayer]

f74264276baf3064901498c1b070df5e0c4db6fc

[Mike Bayer]

Also can't reproduce exactly your description - "precision" is correctly interpreted by the MySQL dialect when specified on the base Float type:

from sqlalchemy import Float, Table, MetaData, Column
from sqlalchemy.schema import CreateTable

f = Float(precision=5, scale=10)

from sqlalchemy.dialects import mysql

print f.compile(dialect=mysql.dialect())

t = Table('foo', MetaData(), Column('x', Float(precision=5, scale=10)))

print CreateTable(t)
print CreateTable(t).compile(dialect=mysql.dialect())

output:

FLOAT(5)

CREATE TABLE foo (
    x FLOAT
)



CREATE TABLE foo (
    x FLOAT(5)
)

[Mike Bayer]

Removing milestone: 0.7.3 (automated comment)