Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On Wed, Sep 13, 2017 at 11:33 PM, Mark Lawrence via Tutor wrote: > SQLAlchemy isn't the only Python ORM of course. There is a useful little > article about ORMs and their availability here > https://www.fullstackpython.com/object-relational-mappers-orms.html. A more >

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On Thu, Sep 14, 2017 at 2:06 AM, Peter Otten <__pete...@web.de> wrote: > That's the "Law of leaky abstractions", > https://www.joelonsoftware.com/2002/11/11/the-law-of-leaky-abstractions/ Thanks for the link to this article. I really enjoyed reading it. In fact, so far every article I have read

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 14Sep2017 09:15, Alan Gauld wrote: On 14/09/17 04:11, boB Stepp wrote: SELECT some, fields (never *) Why no "*"? Does this open up a security vulnerability? Not so much security as resilience to change. If you use * and the data schema changes

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 14/09/17 04:40, boB Stepp wrote: >> mapping your logic layer object models to underlying >> data tables. > > My initial thoughts here are that typically a particular class would > map to a particular table and that each object instance would > correspond to a row in said table. Is this

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 14/09/17 04:11, boB Stepp wrote: >> SELECT some, fields (never *) > > Why no "*"? Does this open up a security vulnerability? Not so much security as resilience to change. If you use * and the data schema changes to include extra fields then your * query returns the extra

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 14/09/2017 00:51, Cameron Simpson wrote: Secondly, there's SQLAlchemy. It knows the dialects and asks you to write "native" looking python syntax for selects etc. So stuff like:  db_conn.select(t.col1 == 9 and t.col2 == 10) where "t" is a "table" object it has handed you. I believe

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

boB Stepp wrote: >> at some point you will need to write database specific SQL or delegate >> that task to a library -- sqlalchemy was already mentioned. I suspect >> that you will then end up learning both the SQL dialects and the ORM >> API... > > I maybe did not realize the full import of

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 12Sep2017 14:05, boB Stepp wrote: As I continue to read about SQL, one thing jumps out: There are many differences between how SQL statements are implemented among the different database products. Even for relatively simple, straightforward things like field

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

I forgot one other thing you mentioned that I had a question about. On Wed, Sep 13, 2017 at 2:41 AM, Alan Gauld via Tutor wrote: > If you limit your SQL to queries fetching raw fields you > should find you are working with the portable subset of > standard SQL most of the

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On Wed, Sep 13, 2017 at 2:55 AM, Peter Otten <__pete...@web.de> wrote: > boB Stepp wrote: >> >> And these would be the SQL commands/statements I would have >> cursor.execute use from the sqlite3 module. They would be different >> depending on which database product I was using. Am I horribly >>

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On Wed, Sep 13, 2017 at 2:41 AM, Alan Gauld via Tutor wrote: > The classic approach is to have 3 tiers in the architecture. > 1) UI layer - usually a GUI toolkit - the VC part of MVC > 2) Business logic - its the M bit of MVC... and where most OOP happens > 3) data access - the

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

2017-09-13 3:58 GMT+02:00 boB Stepp : > On Tue, Sep 12, 2017 at 2:17 PM, Mats Wichmann wrote: > > On 09/12/2017 01:05 PM, boB Stepp wrote: > >> As I continue to read about SQL, one thing jumps out: There are many > >> differences between how SQL

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

boB Stepp wrote: > On Tue, Sep 12, 2017 at 2:17 PM, Mats Wichmann wrote: >> On 09/12/2017 01:05 PM, boB Stepp wrote: >>> As I continue to read about SQL, one thing jumps out: There are many >>> differences between how SQL statements are implemented among the >>> different

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 12/09/17 20:05, boB Stepp wrote: As I continue to read about SQL, one thing jumps out: There are many differences between how SQL statements are implemented usage of SQL. So how does one write one's python program to be DB-agnostic? And if this is impossible, then what is the best way

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On Tue, Sep 12, 2017 at 8:58 PM, boB Stepp wrote: > On Tue, Sep 12, 2017 at 2:17 PM, Mats Wichmann wrote: >> On 09/12/2017 01:05 PM, boB Stepp wrote: >>> As I continue to read about SQL, one thing jumps out: There are many >>> differences between how

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On Tue, Sep 12, 2017 at 2:17 PM, Mats Wichmann wrote: > On 09/12/2017 01:05 PM, boB Stepp wrote: >> As I continue to read about SQL, one thing jumps out: There are many >> differences between how SQL statements are implemented among the >> different database products. Even for

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

(sorry for top posting) There are various SQL abstraction layers for this. I have only used Sqlalchemy. This package has two APIs: query and ORM. You might want to look at the query API. This is closer to SQL than ORM. You can use straight(obj) to inspect the SQL that's emitted

Re: [Tutor] How to write database-agnostic python code? (Is this even possible?)

On 09/12/2017 01:05 PM, boB Stepp wrote: > As I continue to read about SQL, one thing jumps out: There are many > differences between how SQL statements are implemented among the > different database products. Even for relatively simple, > straightforward things like field concatenation. One DB