The line causing the error now is:

with engine.connect() as con:
    rs = con.execute('SELECT DISTINCT last_name, 
first_name,addressee_display, street_address, city, a.name, postal_code, 
f.name as country FROM civicrm_contact c, civicrm_entity_tag d , 
civicrm_address e, civicrm_state_province a, civicrm_country f WHERE c.id = 
d.entity_id and tag_id = 6 and c.id = e.contact_id AND state_province_id = 
a.id  and e.country_id = f.id and  display_name not in ( SELECT 
display_name FROM civicrm_contribution, civicrm_contact c, 
civicrm_entity_tag d WHERE receive_date > \'2005-07-01\' and contact_id = 
c.id and c.id = entity_id and tag_id = 6 )')

This was working fine. (It is just my way of making sure I am connected to 
db and able to retrieve data (the old way).

On Thursday, August 22, 2019 at 6:56:56 PM UTC-4, Ira Fuchs wrote:
>
> Weird. When I go back to just running the SQL query, I now get:
>
> InternalError: (pymysql.err.InternalError) (1115, "Unknown character set: 
> 'utf8mb4'")
> (Background on this error at: http://sqlalche.me/e/2j85)
>
> I seem to be regressing.
>
>
> On Thursday, August 22, 2019 at 6:53:46 PM UTC-4, Ira Fuchs wrote:
>>
>> Strange thing just occurred where I now get an error message that pymysql 
>> module is now missing. I redid a pip install and it seems to get passed 
>> that point and comes back with a new error. This was just running the SQL 
>> query to make sure I could do that. I commented it out of the notebook for 
>> now and went back to just running your converted query. I now get:
>>
>> NameError                                 Traceback (most recent call 
>> last)<ipython-input-11-60d8f90ad86b> in <module>      1 s = Session()      2 
>> subquery = (----> 3     s.query(Entity_Tag.display_name)      4     .filter( 
>>      5         Contribution.receive_date > datetime.date(2005, 7, 1),
>> NameError: name 'Entity_Tag' is not defined
>>
>>
>>
>>
>> On Thursday, August 22, 2019 at 6:37:39 PM UTC-4, Peter Schutt wrote:
>>>
>>> The `ondelete=...` keyword argument is a parameter to the `ForeignKey()` 
>>> constructor, not the `Column`.
>>>
>>> This:
>>>
>>> contact_id = Column(ForeignKey(u'civicrm_contact.id'), ondelete=u'CASCADE', 
>>> nullable=False, index=True)
>>>
>>> Should be this:
>>>
>>> contact_id = Column(ForeignKey(u'civicrm_contact.id', ondelete=u
>>> 'CASCADE'), nullable=False, index=True)
>>>
>>>
>>> On Friday, 23 August 2019 05:16:32 UTC+10, Ira Fuchs wrote:
>>>>
>>>> I fixed the syntax errors and tried your rewritten query but I  got an 
>>>> error in the definitions:
>>>>
>>>> TypeError                                 Traceback (most recent call 
>>>> last)<ipython-input-6-97e6a9952682> in <module>()      7     display_name 
>>>> = Column(String(128, u'utf8_unicode_ci'))      8 ----> 9 class 
>>>> CivicrmContribution(Base):     10     __tablename__ = 
>>>> 'civicrm_contribution'     11 
>>>> <ipython-input-6-97e6a9952682> in CivicrmContribution()     11      12     
>>>> id = Column(INTEGER, primary_key=True, comment=u'Contribution ID')---> 13  
>>>>    contact_id = Column(ForeignKey(u'civicrm_contact.id'), 
>>>> ondelete=u'CASCADE', nullable=False, index=True)     14     
>>>> financial_type_id = Column(ForeignKey(u'civicrm_financial_type.id'), 
>>>> index=True)     15     contribution_page_id = 
>>>> Column(ForeignKey(u'civicrm_contribution_page.id', ondelete=u'SET NULL'), 
>>>> index=True)
>>>> /Users/ihf/anaconda2/lib/python2.7/site-packages/sqlalchemy/sql/schema.pyc 
>>>> in __init__(self, *args, **kwargs)   1382             self.info = 
>>>> kwargs.pop("info")   1383 -> 1384         self._extra_kwargs(**kwargs)   
>>>> 1385    1386     def _extra_kwargs(self, **kwargs):
>>>> /Users/ihf/anaconda2/lib/python2.7/site-packages/sqlalchemy/sql/schema.pyc 
>>>> in _extra_kwargs(self, **kwargs)   1385    1386     def 
>>>> _extra_kwargs(self, **kwargs):-> 1387         
>>>> self._validate_dialect_kwargs(kwargs)   1388    1389     #    @property
>>>> /Users/ihf/anaconda2/lib/python2.7/site-packages/sqlalchemy/sql/base.pyc 
>>>> in _validate_dialect_kwargs(self, kwargs)    287                 raise 
>>>> TypeError(    288                     "Additional arguments should be "--> 
>>>> 289                     "named <dialectname>_<argument>, got '%s'" % k    
>>>> 290                 )    291             dialect_name, arg_name = 
>>>> m.group(1, 2)
>>>> TypeError: Additional arguments should be named <dialectname>_<argument>, 
>>>> got 'ondelete'
>>>>
>>>>
>>>> On Wednesday, August 21, 2019 at 8:55:24 PM UTC-4, Peter Schutt wrote:
>>>>>
>>>>> A couple of typos found re-reading my post, the 
>>>>> Contribution.contact_id with a foreign key definition should be  
>>>>> `contact_id = Column(Integer, ForeignKey('civicrm_contact'), 
>>>>> nullable=False)`, I left out the closing parenthesis to the ForeignKey 
>>>>> constructor.
>>>>>
>>>>> Also, the very last line, I didn't close the parenthesis for the 
>>>>> placeholders example, should read:  "(e.g. `%(tag_id_2)s`) are passed...".
>>>>>
>>>>> Couldn't find a way to edit the original.
>>>>>
>>>>> On Thursday, 22 August 2019 10:43:17 UTC+10, Peter Schutt wrote:
>>>>>>
>>>>>> Hi Ira,
>>>>>>
>>>>>> For example Integer(xx) says that Integer cannot have parameters and 
>>>>>>> Tinyint seems not to exist.
>>>>>>
>>>>>>
>>>>>> I'm aware of sqlacodegen, although never had the need to use it 
>>>>>> myself. Those issues sound to me like it is using the mysql dialect 
>>>>>> types, 
>>>>>> not the standard sqlalchemy types. For example `from sqlalchemy import 
>>>>>> Integer` will not accept an argument but `from sqlalchemy.dialects.mysql 
>>>>>> import INTEGER` does accept display_width as a parameter amongst others. 
>>>>>> Also, `from sqlalchemy import TinyInteger` will raise an import error 
>>>>>> but 
>>>>>> `from sqlalchemy.dialects.mysql import TINYINT` works.
>>>>>>
>>>>>> I presume that this front-end overhead will pay back when I write 
>>>>>>> more interesting scripts that use data from Civicrm. If this works then 
>>>>>>> I 
>>>>>>> can map the remainder of the (many) tables.
>>>>>>
>>>>>>
>>>>>> Well, that's certainly the idea. The abstraction allows for writing 
>>>>>> code that is both easier to write and read. Essentially you write a 
>>>>>> Python 
>>>>>> app and let sqlalchemy handle the bridge between your application and 
>>>>>> the 
>>>>>> database. It's not a magic bullet, there are plenty of sql paradigms 
>>>>>> still 
>>>>>> exposed to you through the ORM and there are limitations to using it, 
>>>>>> primarily performance relative to doing bulk operations (for example, 
>>>>>> see 
>>>>>> here 
>>>>>> <https://docs.sqlalchemy.org/en/13/faq/performance.html#i-m-inserting-400-000-rows-with-the-orm-and-it-s-really-slow>).
>>>>>>  
>>>>>> Like any tool, you need to weigh up the pros and cons. For example, if 
>>>>>> you 
>>>>>> are just using the ORM in order to generate schema or construct raw 
>>>>>> queries, there are better ways. The benefit of the ORM comes once you 
>>>>>> start 
>>>>>> understanding and using the richer feature set. For example, 
>>>>>> relationships.
>>>>>>
>>>>>> In the models that you built above, I notice that you haven't defined 
>>>>>> any foreign keys on columns. I understand that your schema is already 
>>>>>> created and so the foreign keys are already defined at the database 
>>>>>> level, 
>>>>>> but that information is useful to sqlalchemy when you want to create 
>>>>>> relationships 
>>>>>> <https://docs.sqlalchemy.org/en/13/orm/tutorial.html#building-a-relationship>
>>>>>>  and 
>>>>>> explicit joins in your queries. One example of applying a foreign key to 
>>>>>> your columns would be on the `Contribution.contact_id` column. Defining 
>>>>>> that as a foreign key would be as simple as changing the definition to 
>>>>>> `contact_id = Column(Integer, ForeignKey('civicrm_contact', 
>>>>>> nullable=False)`. This would then allow you to define a relationship 
>>>>>> attribute on your Contribution model, e.g. `contact = 
>>>>>> relationship('Contact')`. That allows you to access the instance that 
>>>>>> represents the contact associated with a given contribution through 
>>>>>> instance attribute access, e.g. `contribution_instance.contact` would 
>>>>>> return an instance of `Contact` and sqlalchemy will issue the necessary 
>>>>>> queries behind the scenes to make that happen.
>>>>>>
>>>>>> Now, how to create the equivalent SQL query?
>>>>>>
>>>>>>
>>>>>> Well, I've had to make a couple of guesses to fill in a couple of 
>>>>>> blanks. I assumed that the column in your query `state_province_id` 
>>>>>> should 
>>>>>> be an attribute on the `Address` model, and that the `display_name` 
>>>>>> column 
>>>>>> belongs to the `Entity_Tag` model, as neither of those fields are 
>>>>>> defined 
>>>>>> elsewhere. We haven't spoken about the Session in any detail yet either, 
>>>>>> but you can read 
>>>>>> https://docs.sqlalchemy.org/en/13/orm/tutorial.html#creating-a-session 
>>>>>> if 
>>>>>> you need. I've purely tried to emulate your original query as closely as 
>>>>>> possible.
>>>>>>
>>>>>>     s = Session()
>>>>>>     subquery = (
>>>>>>         s.query(Entity_Tag.display_name)
>>>>>>         .filter(
>>>>>>             Contribution.receive_date > datetime.date(2005, 7, 1),
>>>>>>             Contribution.contact_id == Contact.id,
>>>>>>             Contact.id == Entity_Tag.entity_id,
>>>>>>             Entity_Tag.tag_id == 6,
>>>>>>         )
>>>>>>         .subquery()
>>>>>>     )
>>>>>>     result = (
>>>>>>         s.query(
>>>>>>             Contact.last_name,
>>>>>>             Contact.first_name,
>>>>>>             Address.street_address,
>>>>>>             Address.city,
>>>>>>             Address.postalcode,
>>>>>>             State.name,
>>>>>>             Country.name.label("country"),
>>>>>>         )
>>>>>>         .filter(
>>>>>>             Contact.id == Entity_Tag.entity_id,
>>>>>>             Entity_Tag.tag_id == 6,
>>>>>>             Contact.id == Address.contact_id,
>>>>>>             Address.state_province_id == State.id,
>>>>>>             Address.country_id == Country.id,
>>>>>>             Entity_Tag.display_name.notin_(subquery),
>>>>>>         )
>>>>>>         .distinct()
>>>>>>         .all()
>>>>>>     )
>>>>>>
>>>>>> This query issues this sql:
>>>>>>
>>>>>> SELECT DISTINCT civicrm_contact.last_name AS 
>>>>>> civicrm_contact_last_name, civicrm_contact.first_name AS 
>>>>>> civicrm_contact_first_name, civicrm_address.street_address AS 
>>>>>> civicrm_address_street_address, civicrm_address.city AS 
>>>>>> civicrm_address_city, civicrm_address.postalcode AS 
>>>>>> civicrm_address_postalcode, civicrm_state_province.name AS 
>>>>>> civicrm_state_province_name, civicrm_country.name AS country
>>>>>> FROM civicrm_contact, civicrm_address, civicrm_state_province, 
>>>>>> civicrm_country, civicrm_entity_tag
>>>>>> WHERE civicrm_contact.id = civicrm_entity_tag.entity_id AND 
>>>>>> civicrm_entity_tag.tag_id = %(tag_id_1)s AND civicrm_contact.id = 
>>>>>> civicrm_address.contact_id AND civicrm_address.state_province_id = 
>>>>>> civicrm_state_province.id AND civicrm_address.country_id = 
>>>>>> civicrm_country.id AND civicrm_entity_tag.display_name NOT IN (SELECT 
>>>>>> civicrm_entity_tag.display_name
>>>>>> FROM civicrm_contribution
>>>>>> WHERE civicrm_contribution.receive_date > %(receive_date_1)s AND 
>>>>>> civicrm_contribution.contact_id = civicrm_contact.id AND 
>>>>>> civicrm_contact.id = civicrm_entity_tag.entity_id AND 
>>>>>> civicrm_entity_tag.tag_id = %(tag_id_2)s)
>>>>>>
>>>>>> Notice that the `FROM` clause in the subquery only contains one 
>>>>>> column, this is becuase the other columns have been automatically 
>>>>>> correlated with the columns expressed in the enclosing query. See here: 
>>>>>> https://docs.sqlalchemy.org/en/13/core/tutorial.html#correlated-subqueries
>>>>>> .
>>>>>>
>>>>>> The scalar values in the query that have been substituted with 
>>>>>> placeholders (e.g. `%(tag_id_2)s` are passed to the db driver in 
>>>>>> dictionary 
>>>>>> form along with the query, e.g. `{'tag_id_1': 6, 'receive_date_1': 
>>>>>> datetime.date(2005, 7, 1), 'tag_id_2': 6}`.
>>>>>>
>>>>>> On Wednesday, 21 August 2019 10:20:30 UTC+10, Ira Fuchs wrote:
>>>>>>>
>>>>>>> I noticed that some of the definitions created by sqlacodegen are 
>>>>>>> resulting in errors in python. For example Integer(xx) says that 
>>>>>>> Integer 
>>>>>>> cannot have parameters and Tinyint seems not to exist. Perhaps this is 
>>>>>>> a 
>>>>>>> result of my running a less than current version of mysql?
>>>>>>>
>>>>>>> On Tuesday, August 20, 2019 at 6:58:03 PM UTC-4, Ira Fuchs wrote:
>>>>>>>>
>>>>>>>> Just an aside: I discovered the sqlacodegen tool which will create 
>>>>>>>> the sqlalchemy class definitions automatically. I ran it against the 
>>>>>>>> civicrm mysql db and it worked. The definitions comprise 5881 lines 
>>>>>>>> (428KB). Fortunately I don't need much of it for my purposes.
>>>>>>>>
>>>>>>>> On Tuesday, August 20, 2019 at 6:15:46 PM UTC-4, Ira Fuchs wrote:
>>>>>>>>>
>>>>>>>>> I think I may have all the definitions:
>>>>>>>>>
>>>>>>>>> class Contact(Base):
>>>>>>>>>     __tablename__ = "civicrm_contact"
>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>     last_name = Column(String(20), nullable=False)
>>>>>>>>>     first_name = Column(String(20), nullable=False)
>>>>>>>>> class Contribution(Base):
>>>>>>>>>     __tablename__ = "civicrm_contribution"
>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>     contact_id = Column(Integer, nullable=False)
>>>>>>>>>     receive_date = Column(DateTime,nullable=False)
>>>>>>>>>     total_amount = Column(DECIMAL(precision=20,scale=2), 
>>>>>>>>> nullable=False)
>>>>>>>>> class Address(Base):
>>>>>>>>>     __tablename__ = "civicrm_address"
>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>     contact_id = Column(Integer, nullable=False)
>>>>>>>>>     street_address = Column(String(96), nullable=False)
>>>>>>>>>     city = Column(String(64), nullable=False)
>>>>>>>>>     postalcode = Column(String(64), nullable=False)
>>>>>>>>>     country_id = Column(Integer, nullable=False)
>>>>>>>>> class Country(Base):
>>>>>>>>>     __tablename__ = "civicrm_country"
>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>     name = Column(String(64))
>>>>>>>>> class State(Base):
>>>>>>>>>     __tablename__ = "civicrm_state_province"
>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>     name = Column(String(64), nullable=False)
>>>>>>>>>     abbreviation = Column(String(4), nullable=False)
>>>>>>>>>     country_id = Column(Integer, nullable=False)
>>>>>>>>> class Entity_Tag(Base):
>>>>>>>>>     __tablename__ = "civicrm_entity_tag"
>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>     entity_id = Column(Integer, nullable=False)
>>>>>>>>>     tag_id = Column(Integer, nullable=False)
>>>>>>>>>
>>>>>>>>> Now, how to create the equivalent SQL query?  I presume that this 
>>>>>>>>> front-end overhead will pay back when I write more interesting 
>>>>>>>>> scripts that 
>>>>>>>>> use data from Civicrm. If this works then I can map the remainder of 
>>>>>>>>> the 
>>>>>>>>> (many) tables.
>>>>>>>>>
>>>>>>>>> On Tuesday, August 20, 2019 at 5:15:36 PM UTC-4, Ira Fuchs wrote:
>>>>>>>>>>
>>>>>>>>>> OK, fixed the case:
>>>>>>>>>>
>>>>>>>>>> class Contact(Base):
>>>>>>>>>>     __tablename__ = "civicrm_contact"
>>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>>     last_name = Column(String(20), nullable=False)
>>>>>>>>>>     first_name = Column(String(20), nullable=False)
>>>>>>>>>> class Contribution(Base):
>>>>>>>>>>     __tablename__ = "civicrm_contribution"
>>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>>     contact_id = Column(Integer, nullable=False)
>>>>>>>>>>     receive_date = Column(DateTime,nullable=False)
>>>>>>>>>>     total_amount = Column(DECIMAL(precision=20,scale=2), 
>>>>>>>>>> nullable=False)
>>>>>>>>>>
>>>>>>>>>> On Tuesday, August 20, 2019 at 3:59:55 PM UTC-4, Ira Fuchs wrote:
>>>>>>>>>>>
>>>>>>>>>>> OK, I made some progress (see screenshot).  I don't need the 
>>>>>>>>>>> full model to be represented as I will not need many of the columns 
>>>>>>>>>>> in each 
>>>>>>>>>>> of the tables. If I could flesh this out enough so that I can do 
>>>>>>>>>>> the query 
>>>>>>>>>>> posted above I can probably use that as a template to move forward.
>>>>>>>>>>>
>>>>>>>>>>> On Monday, August 19, 2019 at 7:11:59 AM UTC-4, Peter Schutt 
>>>>>>>>>>> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>> Cool, how about we walk through creating a model for your 
>>>>>>>>>>>> schema as an example. As we go I can point you to the relevant 
>>>>>>>>>>>> sections of 
>>>>>>>>>>>> the tutorials/docs as they are great and will explain the details 
>>>>>>>>>>>> much 
>>>>>>>>>>>> better than I can, and I'll try to address any questions you have 
>>>>>>>>>>>> along the 
>>>>>>>>>>>> way.
>>>>>>>>>>>>
>>>>>>>>>>>> The first thing you need is your Base class, all of your ORM 
>>>>>>>>>>>> models will inherit from this:
>>>>>>>>>>>>
>>>>>>>>>>>> from sqlalchemy.ext.declarative import declarative_base
>>>>>>>>>>>>
>>>>>>>>>>>> Base = declarative_base()
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Your models need to inherit from Base, need a __tablename__ 
>>>>>>>>>>>> class attribute and at least a primary key column. For example, a 
>>>>>>>>>>>> class to 
>>>>>>>>>>>> represent your "db_contact" table might look like this:
>>>>>>>>>>>>
>>>>>>>>>>>> from sqlalchemy import Column, Integer, String
>>>>>>>>>>>>
>>>>>>>>>>>> class Contact(Base):
>>>>>>>>>>>>
>>>>>>>>>>>>     __tablename__ = "db_contact"
>>>>>>>>>>>>
>>>>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>>>>     last_name = Column(String(20), nullable=False)
>>>>>>>>>>>>     first_name = Column(String(20), nullable=False)
>>>>>>>>>>>>
>>>>>>>>>>>> Some things to note this far along:
>>>>>>>>>>>>
>>>>>>>>>>>>    - In this example, the name of the Column in the database 
>>>>>>>>>>>>    is inferred from the name of the class attribute that the 
>>>>>>>>>>>> Column is 
>>>>>>>>>>>>    assigned to.
>>>>>>>>>>>>    - Column constructors take arguments that define specifics 
>>>>>>>>>>>>    of how the column is defined in the database. E.g. 
>>>>>>>>>>>> `primary_key=True`, 
>>>>>>>>>>>>    `nullable=False`. By declaring a single integer column as 
>>>>>>>>>>>> primary key, it 
>>>>>>>>>>>>    will automatically be specified as autoincrement in the schema, 
>>>>>>>>>>>> as well as 
>>>>>>>>>>>>    the primary key. Setting nullable=False on other columns 
>>>>>>>>>>>> declares that a 
>>>>>>>>>>>>    NOT NULL constraint should be set on those columns.
>>>>>>>>>>>>    - As you are using MySQL, String types (which represent 
>>>>>>>>>>>>    VARCHAR type in the database) require a length. If you were 
>>>>>>>>>>>> creating models 
>>>>>>>>>>>>    for other backends such as SQLite or postgres, then that isn't 
>>>>>>>>>>>> required.
>>>>>>>>>>>>
>>>>>>>>>>>> Nothing that I've covered here isn't covered in the early 
>>>>>>>>>>>> stages of the ORM Tutorial 
>>>>>>>>>>>> <https://docs.sqlalchemy.org/en/13/orm/tutorial.html#declare-a-mapping>.
>>>>>>>>>>>>  
>>>>>>>>>>>> Also, you can read the Column API 
>>>>>>>>>>>> <https://docs.sqlalchemy.org/en/13/core/metadata.html#sqlalchemy.schema.Column>
>>>>>>>>>>>>  to 
>>>>>>>>>>>> get a feel for the arguments that you can pass to Column in order 
>>>>>>>>>>>> to define 
>>>>>>>>>>>> your schema.
>>>>>>>>>>>>
>>>>>>>>>>>> One more important element is the Foreign Key. I'll use your 
>>>>>>>>>>>> "db_entity_tag" table to give you an example of that:
>>>>>>>>>>>>
>>>>>>>>>>>> from sqlalchemy import ForeignKey
>>>>>>>>>>>>
>>>>>>>>>>>> class EntityTag(Base):
>>>>>>>>>>>>
>>>>>>>>>>>>     __tablename__ = "db_entity_tag"
>>>>>>>>>>>>
>>>>>>>>>>>>     id = Column(Integer, primary_key=True)
>>>>>>>>>>>>     entity_id = Column(
>>>>>>>>>>>>         Integer, 
>>>>>>>>>>>>         ForeignKey('db_contact.id', ondelete="CASCADE"), 
>>>>>>>>>>>>         nullable=False,
>>>>>>>>>>>>     )
>>>>>>>>>>>>
>>>>>>>>>>>> Pass the name of the related column to the ForeignKey object 
>>>>>>>>>>>> (note that this isn't "Class.attributename", it is 
>>>>>>>>>>>> "tablename.columnname") 
>>>>>>>>>>>> and pass the ForeignKey object as a positional argument to the 
>>>>>>>>>>>> Column 
>>>>>>>>>>>> constructor _after_ the column type argument. ForeignKey api is 
>>>>>>>>>>>> documented 
>>>>>>>>>>>> here 
>>>>>>>>>>>> <https://docs.sqlalchemy.org/en/13/core/constraints.html#sqlalchemy.schema.ForeignKey>
>>>>>>>>>>>>  and 
>>>>>>>>>>>> touched on in the orm tutorial here 
>>>>>>>>>>>> <https://docs.sqlalchemy.org/en/13/orm/tutorial.html#building-a-relationship>
>>>>>>>>>>>> .
>>>>>>>>>>>>
>>>>>>>>>>>> Have a go at filling in the columns that I've missed in those 
>>>>>>>>>>>> models above and defining the rest of the tables in your schema 
>>>>>>>>>>>> and once 
>>>>>>>>>>>> you get that done we can move on. Happy to try to answer any 
>>>>>>>>>>>> questions you 
>>>>>>>>>>>> might have along the way.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> On Monday, 19 August 2019 12:36:21 UTC+10, Ira Fuchs wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>> Thanks for your reply and offer to help. I am able to create 
>>>>>>>>>>>>> an Engine and connect to the MySQL db. I can execute simple sql 
>>>>>>>>>>>>> queries 
>>>>>>>>>>>>> although I wasn't able to get the query I posted to work due to a 
>>>>>>>>>>>>> syntax 
>>>>>>>>>>>>> error (probably having to do with the quotes). I have not mapped 
>>>>>>>>>>>>> any tables 
>>>>>>>>>>>>> to classes.
>>>>>>>>>>>>>
>>>>>>>>>>>>> On Sunday, August 18, 2019 at 8:54:57 PM UTC-4, Peter Schutt 
>>>>>>>>>>>>> wrote:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Hi Ira, I'd be happy to help you find your feet with the 
>>>>>>>>>>>>>> SQLAlchemy ORM.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> In general when creating an application that uses the 
>>>>>>>>>>>>>> SQLAlchemy ORM, you would start with an Engine (for connecting 
>>>>>>>>>>>>>> to the db), 
>>>>>>>>>>>>>> a declarative base class (maps db table to python class) and a 
>>>>>>>>>>>>>> Session 
>>>>>>>>>>>>>> instance (for using a connection to issue queries). Do you have 
>>>>>>>>>>>>>> any 
>>>>>>>>>>>>>> familiarity with those concepts?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> On Monday, 19 August 2019 02:34:05 UTC+10, Ira Fuchs wrote:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> I am new to sqlalchemy and I would like to begin using it to 
>>>>>>>>>>>>>>> create scripts with some sql queries that I have been using but 
>>>>>>>>>>>>>>> need to 
>>>>>>>>>>>>>>> change from time to time. It would help a lot if someone could 
>>>>>>>>>>>>>>> translate 
>>>>>>>>>>>>>>> one of these queries to python sqlalchemy using an ORM (not 
>>>>>>>>>>>>>>> simply 
>>>>>>>>>>>>>>> executing the query as is) so that I could use this as a 
>>>>>>>>>>>>>>> template for other 
>>>>>>>>>>>>>>> queries, or at least learn from it.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> One of my queries looks like this:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> SELECT DISTINCT last_name, first_name, street_address, city, 
>>>>>>>>>>>>>>> a.name, postal_code, f.name as country FROM db_contact c, 
>>>>>>>>>>>>>>> db_entity_tag d , db_address e, db_state_province a, db_country 
>>>>>>>>>>>>>>> f WHERE 
>>>>>>>>>>>>>>> c.id = d.entity_id and tag_id = 6 and c.id = e.contact_id 
>>>>>>>>>>>>>>> AND state_province_id = a.id  and e.country_id = f.id and  
>>>>>>>>>>>>>>> display_name not in ( SELECT display_name FROM db_contribution, 
>>>>>>>>>>>>>>> db_contact 
>>>>>>>>>>>>>>> c, db_entity_tag d WHERE receive_date > '2005-07-01' and 
>>>>>>>>>>>>>>> contact_id = 
>>>>>>>>>>>>>>> c.id and c.id = entity_id and tag_id = 6 )
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Thanks for any help.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>

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http://www.sqlalchemy.org/

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