in my Database (psql) I’ve got a table named offers_offer and inside that there is an column named offer_name, which is wrong, because it should actually be just name. I don’t know why it has this name, but due to this I can’t load any fixtures or create a new object, because I always receiv…
Tag: database
Replacing values greater than a number in pandas dataframe
I have a large dataframe which looks as: I want to replace each element greater than 9 with 11. So, the desired output for above example is: Edit: My actual dataframe has about 20,000 rows and each row has list of size 2000. Is there a way to use numpy.minimum function for each row? I assume that it will be
Database connection string parsing in python
Given a database connection string structure (such like one you can find here) what’s the best way to parse a real URI string and get their component like user, password, database name and host? Thank you very much Answer There is a Python library for that: python 2: urlparse python 3: urllib.parse
Confusion between prepared statement and parameterized query in Python
As far as I understand, prepared statements are (mainly) a database feature that allows you to separate parameters from the code that uses such parameters. Example: A parameterized query substitutes the manual string interpolation, so instead of doing we can do Now, it seems that prepared statements are, for …
What is the simplest way to retry a Django view upon an exception being raised?
I want to rerun a Django view function if a certain exception is raised (in my case a serialization error in the underlying database). I want it to run with exactly the same parameters, including the same request object – as if the client had re-requested the URL. There are many database queries in the …
Get all keys in Redis database with python
There is a post about a Redis command to get all available keys, but I would like to do it with Python. Any way to do this? Answer Use scan_iter() scan_iter() is superior to keys() for large numbers of keys because it gives you an iterator you can use rather than trying to load all the keys into memory. I
Converting BLOB, stored on a database, to an image on an HTML website
This is my first question. I am having users upload their own image to a database. That image is stored as a BLOB. I was able to do this successfully. I am using MySQL for the database. The part I am having trouble with is displaying that BLOB as an image on the website when its called upon. Right now
Is there a way to get a list of column names in sqlite?
I want to get a list of column names from a table in a database. Using pragma I get a list of tuples with a lot of unneeded information. Is there a way to get only the column names? So I might end up with something like this: [Column1, Column2, Column3, Column4] The reason why I absolutely need this list
sqlite3.OperationalError: unable to open database file
I get this error when setting up a server in Django. It is sqlite3 which means it should create the .db file but it doesn’t seem to be doing so. I’ve stipulated SQLite as the backend and an absolute file path for where to put it, but no luck. Is this a bug or am I doing something incorrect? (Was
Select NULL Values in SQLAlchemy
Here’s my (PostgreSQL) table — I want to select all people that are not known to be married, i.e., including those with NULL marriage_status. This does not work — Of course this does — The problem is that I’m accessing it from SQLAlchemy with — which gets translated to R…