So I made a very simple module that takes those sql files and turns them into SQLAlchemy text objects with variables in them.
Would it be possible to add something like this to the project or does it require many sql parsing libraries etc. to ensure sql validity to find variables in the sql file?
https://nl1.outband.net/fossil/query/file?name=query.py&ci=t...
In short you have your query in file sql/dept_personal.sql and you call it like
for row in q.dept_personal(db_cursor, department='manpower'):As for CI there are pre-commit hooks I suspect could be used for that process. https://fossil-scm.org/home/help/hook and https://fossil-scm.org/home/doc/trunk/www/hooks.md
Because their lists don't have selection by bare words, they have to go one of several other specialized, distinct, built-in Abstract Data Types to get it. They have to create whole so-called "Classes" and "Modules", when all they really needed was a list whose elements can be accessed with a dot and a bare word.
The pandas package for tabular data manipulation requires even more complicated workarounds. It has a DataFrame Class composed of objects of Column Class. Then it makes an arbitrary bunch of common functions, so common that many are built into Python itself, Methods of said Columns. (In R, a table is just a list of vectors, and no Methods are needed.)
So now you've got a thing that's supposedly a real Class, but it's really just a container of completely arbitrary fields and data types. These fields are themselves instances of another Class that is supposedly specific to pandas, but is really just a vector, and a vector doesn't necessarily have anything to do with being part of a table. And that Class has some random methods that give you additional ways to do basic things the language already does, and are often not the functions you actually need to work with the data therein.
All that just so that we can write stuff like df.col.max(), and... gosh, what is that even supposed to mean? Can we all just admit that we like writing code in chains separated by dots, and stop tying that capability to hierarchies of Official Abstract Data Types?
These non-R languages make you utter such strange incantations just to put something in a key-value container and access that thing with nice-looking code. I feel like this makes it harder to realize that very often this is the best way of doing things.
R has a bit more varied and sometimes mildly ugly syntax than other languages, but once you get used to the building blocks it gives you, it has all these powers to do very dynamic things in very easy ways, without a bunch of ponderous specialized concepts.
The strange thing here seems to be R’s use of ”list” as a name for a map-like key-value structure. The word ”list” is commonly understood to refer to a data structure which needs to be linearly (linked list) or partially (skiplist) iterated through to access a value at a particular index.
My impression is that JavaScript is another language like R that values flexibility a lot.
And yeah, I agree that R is rather casual about lists vs maps. It doesn't really care that maps are a great data structure in their own right. It just wants to slap names on list elements when it's convenient to access elements of the list by name.
Sql has “tuples” for the rows of a result-set which are neither tuples nor lists in the “general sense” and are of a “record” type - names with values.
So what is a list? Depends on the context.
The downside is that parameterized queries are a bit of a chore; for example, if a query should support an optional filter on user_id, you need to craft it like this:
WHERE ...
AND CASE
WHEN sqlc.narg('user_id') IS NOT NULL THEN sqlc.narg('user_id')
ELSE true
END
This is not too bad, though, and the conditionals get optimized away by the database planner.I feel the same, hence why I prefer a Django-like ORM to SQLAlchemy in spite of all the praises it gets. The author says "SQLAlchemy is the best. I don't like the API or codebase of the others", but actually what he describes feels like the Django ORM (or Tortoise, or many others).
Also, sometimes just a thin layer above SQL is fine. For small personal projects I use my own wrapper above sqlite like so:
import oora
from dataclasses import dataclass
db = oora.DB(
db_path=":memory:", # or /path/to/your/db.sqlite3
# migrations are just pairs of key=>val where key is an arbitrary (but unique) label and val is a SQL script or a callable.
# If val is a callable, it must take a sqlite3.Cursor as first parameter.
# migrations are executed in order
migrations={
# here's an initial migration:
"0000": "CREATE TABLE IF NOT EXISTS user(id INTEGER PRIMARY KEY, name TEXT UNIQUE NOT NULL);",
# simulating a schema evolution, let's add a field:
"0001": "ALTER TABLE user ADD COLUMN email TEXT NULL;",
},
)
db.migrate()
db.insert("user", {"name": "John"})
db.insert("user", {"name": "Jack"})
db.insert("user", {"name": "Jill"})
# dataclasses are perfect to represent rows
# while still allowing custom behaviour
@dataclass
class User:
id: int
name: str
email: str
def __str__(self):
return self.name
# fetch a random instance
user = db.hydrate(User, db.execute("select * from user ORDER BY RANDOM() limit 1").fetchone())
print(f"User(id {user.id}), original name: {user}")
# change name and email
user.name = "Richard"
user.email = "richard@acme.tld"
db.save(user) # name of table is infered from the dataclass name
print(f"User(id {user.id}), updated name: {user} <{user.email}>")
# persist changes
db.commit()import oora
from dataclasses import dataclass
db = oora.DB(
db_path=":memory:", # or /path/to/your/db.sqlite3
# migrations are just pairs of key=>val where key is an arbitrary (but unique) label and val is a SQL script or a callable.
# If val is a callable, it must take a sqlite3.Cursor as first parameter.
# migrations are executed in order
migrations={
# here's an initial migration:
"0000": "CREATE TABLE IF NOT EXISTS user(id INTEGER PRIMARY KEY, name TEXT UNIQUE NOT NULL);",
# simulating a schema evolution, let's add a field:
"0001": "ALTER TABLE user ADD COLUMN email TEXT NULL;",
},
)
db.migrate()
db.insert("user", {"name": "John"})
db.insert("user", {"name": "Jack"})
db.insert("user", {"name": "Jill"})
# dataclasses are perfect to represent rows
# while still allowing custom behaviour
@dataclass
class User:
id: int
name: str
email: str
def __str__(self):
return self.name
# fetch a random instance
user = db.hydrate(User, db.execute("select * from user ORDER BY RANDOM() limit 1").fetchone())
print(f"User(id {user.id}), original name: {user}")
# change name and email
user.name = "Richard"
user.email = "richard@acme.tld"
db.save(user) # name of table is infered from the dataclass name
print(f"User(id {user.id}), updated name: {user} <{user.email}>")
# persist changes
db.commit()Your pattern of re-interpreting __doc__ is kinda weird though. Why not just add a `return` statement?
Our queries are typically large, not 3-5 liners.
(Filter view queries where you might add additional CTA’s to provide the necessary filter conditions, but aren’t desirable if particular filter parameter is nill, etc.)
Be very careful if you ever use bare string formatting to construct your queries.
with engine: fn(args)
I would rather have
with engine: fn(args, engine)
This makes testing way easier.
Rajni07•2mo ago
gmac•2mo ago