Programming Error when trying to delete User in Django Admin Panel - django

I got a web page online and everything works fine. Except when I try do delete a user I get the following error:
{ProgrammingError at /admin/auth/user/
operator does not exist: text = integer
LINE 1: ...OIN "auth_user" ON ("avtimessolver"."employee_id" = "auth_us...
^
HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.}
I am using Django with nginx, gunicorn and postgresql.
Is there anything wrong with my model? The table avtimessolver is generated by an algorithm where i save the id as names so that Django displays names rather than ids in some queries.
Is there any way to fix this without changeing the table, so that the delete function also accepts user names as input?
Any help is appreciated.

Related

Migrating Django TextChoices to IntegerChoices

In Django (3.2.8), I have a set of TextChoices, which I would like to change to IntegerChoices. I will keep the keys the same, just the values in the database stored will just differ. I do this for consistency and I'm fixing some legacy code.
Naturally, I changed the TextChoices to IntegerChoices, and the corresponding field to an IntegerField. As expected however, upon migrating, I get a django.db.utils.DataError: invalid input syntax for type integer: "option1". I feel like there should be a way that I can define a mapping for this migration to happen, but wasn't able to find any documentation on this.

Best index for a Django model when filtering on one field and ordering on another field

I use Django 2.2 linked to PostgreSQL and would like to optimise my database queries.
Given the following simplified model:
class Person(model.Models):
name = models.CharField()
age = models.Integerfield()
on which I have to do the following query, say,
Person.objects.filter(age__gt=20, age__lt=30).order_by('name')
What would be the best way to define the index in the model Meta field so as to optimise the query?
Which of these four options would be best?
class Meta
indexes = [models.Index(fields=['age','name']),
models.Index(fields=['name','age']),
models.Index(fields=['name']),
models.Index(fields=['age'])]
Is it, for example, possible to prevent sorting when the query is done? Thank you.
This is really a postgres question, as much as a Django question, right?
I think there is a good chance that creating an index on your sort field will help with performance. But there are a lot of caveats and if it's really important to you, you might want to do some testing focused on Postgres (ie, just run some queries in psql and see what happens). Some caveats include:
it might depend on which type of index is created for you by Django
Postgres, of course, does not always use index anyway when running a query but it should if you've got the right one and the right query (and if there is enough data in the table to justify loading the index)
it might matter how your SELECT is formatted by Django
I suggest you create your model and specify that you want the index. Then use Django Debug Toolbar to find out what SELECT query is really getting run. Then, open a dbshell with manage.py dbshell (aka psql) and run ANALYZE with that same select. Assuming you can interpret the output, you will see for yourself whether your index is coming in to play. Paste the ANALYZE output here, if you like.
According to this Postgres documentation ORDER BY can be assisted by a btree index. The b-tree type of index is what Django will create for you by default.
So, why don't you try this:
class Meta:
indexes = [models.Index(fields=['age', 'name'])]
Then go run an EXPLAIN ANALYZE in dbshell and see whether it worked.
# You should apply indexing on age, because you are searching for 'age' column data
indexes = [
models.Index(fields=['age'])
]

Drupal 8: Altering Search API queries

I'm working on a project which includes the following activated modules:
Drupal core 8.2.3
Database Search 8.x-1.0-beta4
Search API 8.x-1.0-beta4
Search API Term Handlers 8.x-1.0-beta4
Views 8.2.3
I have a list of nids which need to be excluded from the search result of the site-wide search. The search uses Search API and has been setup using Views.
The table in the database is: "search_api_db_default_index"
The field I wish to target is: "nid"
I wasn't able to get HOOK__search_api_query_alter or HOOK_search_api_results_alter to fire, so I am attempting to manipulate the query through HOOK_views_query_alter.
I have attempted to use both the "addWhere" and "addCondition" methods with the following syntax:
When using the addCondition method, I attempted
$query->addCondition('search_api_db_default_index.nid', $oneBadNid, '<>');
and
$query->addCondition('search_api_db_default_index.nid', $manyBadNids, 'NOT IN');
and when using the addWhere method, I attempted
$query->addWhere('AND', 'search_api_index_default_index.nid', $oneBadNid, '<>');
and
$query->addWhere('AND', 'search_api_index_default_index.nid', $manyBadNids, 'NOT IN');
Regardless of whether or not I prefix the field with the table name, searching always results in triggering the following notice:
Unknown field in filter clause: 'search_api_db_default_index.nid' .
It seems that the field name is always wrapped in an html encoded string representing a single quotation, but this occurs both when using double quotations or single quotations around the supplied table.field parameter.
I am not even sure that this is what is keeping me from altering my query, but it is the only thing close to an error which I have discovered in this process. It's also possible that I'm simply not supposed to be targeting the table in the manner written, but I did not find any documentation directing me to the proper methodology.
I would appreciate any insight into this issue! Thanks!
Generally you can use
$fields = $query->getIndex()->getFields();
on the query to get an array of fields you can use within the search_api query.
Piggy-backing off of Nebel54's comment, and attempting this on my own, you don't need to include the 'table' name when setting the addCondition. However, I did need to use hook_search_api_query_alter over a views-specific one.
function mymodule_search_api_query_alter(\Drupal\search_api\Query\QueryInterface &$query) {
// Ensure field_myfield is being indexed
$fields = $query->getIndex()->getFields();
if (isset($fields['field_myfield'])) {
$query->addCondition('field_myfield', 'myvalue', '<>');
}
}

Django show options

I have a database filled with values for first_name. I also made a form, which calls for an input of first_name. How can i give the user suggestions as they type of names that are already in the database?
Also, if i have someone entering 2 in one integerfield, and a 3 in another integerfield, how can i autocompute the product and show it in real-time?
The package https://github.com/yourlabs/django-autocomplete-light seems to be what you're looking for.
It allows the end user to type some characters, after which it will be autocompleted/suggested from what's already in the DB.
For autocomputing the two intergerfields, I'd go for client-side (Javascript).

Adding data to database in django issue

I have code like this:
form = TestForm(request.POST)
form.save(commit=False).save()
This code sometimes work sometimes dont. Problem is in auto increment id.
When i have some data in db that is not written by django and i want to add data from django i get IntegrityError id already exists.
I i have 2 rows in db(not added by django) i need to click "add data" 3 times. After third time when id increment to 3 all is ok.
How to solve this?
These integrity errors appear, when your table sequence is not updated after new item is created. Or if sequence is out of sync with reality. For example - you import items from some source and the items also contain id, which is higher than your table index sequence indicates. I have not seen a case where django messes sequences up.
So what i guess happens is, that the other source that inserts data into your database, also inserts id's and sequence is not updated. Fix that and your problems should disappear.