194,094 questions
Best practices
0
votes
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12
views
Advise of best practices for updating and deleting vectors in a large PolarDB table?
My application requires that vector embeddings are frequently updated or deleted. For example, when a user edits a blog post, its corresponding text embedding needs to be re-calculated and updated in ...
- 471
Tooling
0
votes
0
replies
35
views
What database to choose?
I'm analysing a case that a data warehouse can be used instead of CRM - as a base that collect all information about customers, offers, invoices and soon.
I will scrape data from 3 already existing ...
- 1
0
votes
1
answer
52
views
What is the practical difference between static and dynamic background workers in PostgreSQL?
I’m trying to understand when to use a static background worker vs a dynamic one in PostgreSQL.
From what I know so far:
Static workers are registered during postmaster startup
Dynamic workers can be ...
- 53
Advice
0
votes
3
replies
63
views
PostgreSQL: primary key based on timestamp
I am working on a highload system, which needs to process quite a lot of events, but not an insanely huge amount. The data ingested has to be editable during a short period of time, and then the need ...
- 9,790
0
votes
1
answer
21
views
Neo4j has issues with loading Reactome Graph Database
I have been trying to start exploring the Reactome Graph Database today following the instructions given at https://reactome.org/dev/graph-database#GetStarted
I have installed Neo4j Desktop 2 (version ...
- 301
Advice
0
votes
0
replies
13
views
ER Model and Scheduling Logic for a Pet Grooming Appointment System
Function Table
ER Model
I am currently designing the database schema for a Pet Grooming Appointment System (focusing solely on the appointment functionality, excluding user registration). I've ...
- 1
Best practices
3
votes
5
replies
140
views
Fastest way to read 10M DB rows in Python?
I’m trying to efficiently read about 10 million rows (single column) from a database table in Python and I’m not sure if my current approach is reasonable or if I’m missing some optimizations.
...
1
vote
0
answers
83
views
Heavy duplication when upserting with GORM generics in SQLite
I have several models in my application, which have associations between each other. I'm trying to recursively upsert them, but haven't been able to find a good solution that doesn't extensively rely ...
- 49
0
votes
0
answers
33
views
PolarDB vector database data import
I tried to import some MD files into PolarDB vector database. Some files hit errors like follow:
Failed file: monthly_2021_07_05.md
Log file: import_with_errors.log
Error context:
2025-10-28 17:23:07,...
- 21
Tooling
0
votes
4
replies
71
views
Is there a Database First approach in Java like Entity Framework in C#?
I’m used to working with a Database First approach in C#. I design my database schema (often with MySQL Workbench) and do a forward engineering, then generate my C# models using Entity Framework’s. ...
-2
votes
1
answer
70
views
Online clothing store: Which tables are well normalized and which need to be normalized? [closed]
The project is a database for an online clothing store.
Which tables are well normalized and which need to be normalized?
DB schema of all the tables before doing any normalization:
https://i.sstatic....
Best practices
0
votes
0
replies
51
views
How to physical, logical model your unstructured data
If I have data lake.. which have a lot of files and data.. structured and un structured .. is it the correct place , or what is the best practice to create the physical, logical model of my data.. ...
- 49
2
votes
0
answers
124
views
Can not mark more then one line in DBeaver
I am facing an issue in DBeaver.
I always update my DBeaver program when it says to update, and I am using a MAC.
The version of DBeaver is 25.2.5.202511161745.
I try to mark via the mouse more than ...
- 1,267
0
votes
0
answers
47
views
How to handle contention at scale?
We’re building a system where an offer can be redeemed until a global limit is reached.
For example, an offer may allow a maximum total redeemable amount (e.g., 10M), or/and only allow each user to ...
- 657
Advice
0
votes
2
replies
104
views
Force all character columns in a list of data frames to UTF-8 before uploading to a UTF-8-only database
I have a list of two tables in R.
Each data frame contains several character and numeric columns. One of the columns is a company name column (for example, Company_Name).
The target database only ...
- 1
1
vote
0
answers
99
views
DB query execution hanging in golang
I don’t understand why this is happening. I’m using the Go database package to connect to a PostgreSQL database. I loop through fullmsg (88 messages), but after processing about 27 messages, ...
- 46
1
vote
1
answer
169
views
Prisma CLI Error: "Missing required environment variable: DATABASE_URL" in NestJS Project (Even Though .env Is Set) [closed]
I'm trying to use Prisma in my NestJS project. Prisma initializes correctly, but whenever I run any Prisma CLI command (e.g., npx prisma, npx prisma migrate dev, etc.), I get this error:
Failed to ...
Advice
0
votes
1
replies
57
views
How can I truncate the 15 lkh data set which is unfiltered to filter then upload on MySQL
I want that the data will arrange in a proper manner firstly the data have clear and remove duplicate and missing values then I write a my code in pandas to upload and process the same thing again ...
Advice
1
vote
11
replies
126
views
What exactly is a "connection trap"?
In Codd's A Relational Model of Data for Large Shared Data Banks the following paragraph seems to be one of his justifications for the relational model:
A lack of understanding of relational ...
- 685
0
votes
2
answers
110
views
Write logs to database in quarkus application
How can I write my log messages to database in my quarkus application?
I tried to create a ExtHandler like this:
package org.myorg;
import io.agroal.api.AgroalDataSource;
import jakarta.enterprise....
0
votes
2
answers
107
views
Excel Macro Loop. Looking for code to loop through entire workbook
I am new to making macros and have basically no experience with VBA. However, I have managed to cobble together the code below.
The code is supposed to load data from a worksheet (the name of which I ...
Advice
0
votes
2
replies
87
views
Process improvements, A company wants to incorporate AI but the current process hadn't change in 25 years
Goal
The company wants to grow and take advantage of the AI revolution. But there is no roadmap and the current process limits their growth capability. The current process is about 20% automation and ...
- 67
-1
votes
0
answers
30
views
Getting Trending Items from FireStore [duplicate]
I am trying to use firestore and get a top list of items saved into the database. I want for example the top newest, top most worn, and top trending.
An item in the datastore looks something like this....
Advice
1
vote
1
replies
38
views
Why do B-tree disk optimizations work when the OS controls physical disk layout?
I understand the standard explanation for why B-trees are used in databases: they minimize disk seeks by packing many keys into each node, keeping the tree shallow (3-4 levels), and enabling efficient ...
- 11
Best practices
0
votes
5
replies
97
views
How to handle a “ghost” product in a SellDetails table without breaking normalization?
I'm developing a desktop application for gym management. One feature is a store for selling memberships and products.
My client sometimes wants to sell something that is not in the inventory or ...
- 11
Advice
0
votes
1
replies
91
views
If serialisability is enforced in the app/middleware, is it safe to relax DB isolation (e.g., to READ COMMITTED)?
I’m exploring the trade-offs between database-level isolation and application/middleware-level serialisation.
Suppose I already enforce per-key serial order outside the database (e.g., productId) via ...
- 915
0
votes
1
answer
42
views
Revoking Connected Devices: How to Invalidate IMemoryCache Immediately to Prevent 2-Minute Access Window?
Hey i was building a DeviceService to know Connected Devices to an account after i builded every thing now i got issue with revoking device
Main Confusion :
that i decided to use IMemoryCache to ...
Advice
0
votes
3
replies
72
views
Serialization for database?
Lately I've been curious about databases so I am reading books and trying to do simple assignments to learn more about them. I read about pages which contain rows and that's all good but how do I ...
- 433
Best practices
0
votes
0
replies
33
views
How would one draw an ERD for this question?
How would this relational schema be drawn as an ERD? My attempt is shown above, though it is incorrect. I do not understand why. Here is the relational schema:
CREATE TABLE student
(
name TEXT,
...
- 21
-2
votes
0
answers
49
views
Best way to model optional foreign keys when only one should be set [duplicate]
I’m designing an Entity-Relationship diagram as the basis for a relational database.
A timetable planner for a comprehensive school needs to decide, when creating a new lesson, whether the lesson is a ...
- 387
2
votes
1
answer
75
views
Purpose of WriteCommitted isolation transaction level (Golang database/sql package)
In Golang, database/sql package, there is a constant such as LevelWriteCommitted for the IsolationLevel type
https://pkg.go.dev/database/sql#IsolationLevel
What is the purpose of this level? There is ...
- 46
0
votes
1
answer
107
views
How to run a SQL script in Java NOT on startup?
I have a Spring application which is multi-tenant (uses JdbcTemplate for data access). There are several tables creates for each tenant, and I want to keep this SQL code in a separate init_tenant.sql ...
- 2,885
2
votes
1
answer
91
views
Django transaction.atomic() on single operation prevents race conditions?
Why I need to use atomic() when I have only 1 db operation inside atomic block? My AI-assistant tells me that it prevents race conditions, but I don't use select_for_update() inside. It tells that db ...
- 66
0
votes
1
answer
88
views
Database data missing when reading - ASP NET MVC
I'm working on a messaging platform type sales platform. A buyer can contact a seller about a product. Their message concerns a specific product.
The exchange of messages is only possible between a ...
- 35
0
votes
1
answer
218
views
Can't insert rows into Supabase profile table even after creating the RLS policy to do so for the sign up feature
I am quite new to Supabase.
Basically, I am doing auth using Supabase and have this table called "profiles" with columns:
id - UUID
username - text
email - text
Now when I create a new ...
0
votes
1
answer
40
views
Upsert! Operation Throws "A table can't contain duplicate column names" Error
I have a base table A and a result table B in DolphinDB. Table B was initially empty and is used to store calculated results based on table A. When trying to insert the calculated results into table B,...
- 1
0
votes
0
answers
36
views
Smart way to get latest values in AceBase
My vehicle logbook app stores the data of the trips. It should also store the changes made to a specific trip; thus, anyone can see if and what data has been changed after the first entry of the trip. ...
- 76
0
votes
1
answer
95
views
aiosqlite and managing transactions
aiosqlite's own documentation is extremely minimal so I would appreciate help from experts.
I have a chat client project and the backend is in Python/FastAPI, with all the relevant calls being async ...
- 1,115
1
vote
1
answer
73
views
How to handle inserts and updates on postgres temporal tables?
I have couple temporal tables in my db.
CREATE TABLE temporal (
version_id SERIAL PRIMARY KEY,
some_id TEXT,
some_data TEXT,
valid_from TIMESTAMP NOT NULL DEFAULT ...
- 1,869
0
votes
2
answers
75
views
Can a partial multikey index in MongoDB index only certain subdocuments of an array?
I have a MongoDB collection with documents containing an array of subdocuments. For example:
{
"_id": 1,
"addresses": [
{ "city": "New York", "...
0
votes
0
answers
61
views
ADBC Flight SQL query on StarRocks database drops column names
I am using the ADBC Flight SQL driver to query a StarRocks database. This works well (and is insanely fast) when the query is a SELECT on a single table. But as soon as I add a JOIN to the query, all ...
- 402
-1
votes
1
answer
48
views
How to correctly use retry_delay or retry_delay_sec in Airflow YAML DAG?
I'm currently working with Apache Airflow and trying to configure retries for my DAG tasks using the retry_delay (or retry_delay_sec) parameter in a YAML-based DAG definition.
However, I'm running ...
0
votes
0
answers
65
views
Connect to EViews data base in R
I have an Eviews data base which is stored in an .edb file (along with an .e0, .e1a, and and .e1b file). Is there any way I can read from (and optimally also write to) this DB with R?
I am aware of ...
- 57
0
votes
0
answers
51
views
Redis data structure and storage optimzation
I have an application which keeps appending data for a wide range of sessionIDs and expiring them in a few hours, currently we use Redis List data structure and having the SessionID as the key.
For ...
0
votes
1
answer
78
views
In three-layer architecture, what do layer dependencies start to look like when OOP objects are involved in the Business layer?
As a coding test I've been tasked with developing a toy three-layer architecture DBMS project, involving OOP principles. The three-layer stuff isn't strictly my background so I've been trying to study ...
- 11
0
votes
1
answer
40
views
Effective pagination for descending order queries in DynamoDB
I have an use-case of building a news feed for which I store the articles along with the timestamps in a DynamoDB table. I want to build infinite scrolling capability, and retrieve the article with ...
- 187
0
votes
0
answers
93
views
The Laravel project on production continues to give database connection error intermittently
The Laravel project on production continues to show the error below intermittently:
SQLSTATE[HY000] [1130] Host 'localhost' is not allowed to connect to
this MariaDB server (Connection: mysql, SQL: ...
- 1,220
1
vote
0
answers
47
views
makeblastdb Error: Duplicate seq_ids GNL|BL_ORD_ID|90650 despite unique FASTA headers and version 4 database
I’m trying to build a BLAST nucleotide database using makeblastdb (NCBI BLAST 2.16.0) inside a Singularity container. My FASTA headers have been renamed to be unique in the format:
>file<file#&...
- 75
1
vote
2
answers
136
views
Laravel stancl/tenancy: Tenant migrations "Nothing to migrate" (separate tenant DBs, migrations in database/migrations/tenant)
I am running tenant new migration (orders_table migration) that live in database/migrations/tenant/ . Each tenant has its own database (tenant_1, tenant_2, tenant_3, ...)
and there are some tables ...
- 495
0
votes
0
answers
59
views
Error seeding data: [AppwriteException: Invalid document structure: Missing required attribute "image"]
Working on a react native app and having issues with the Appwrite database.
here is the error:
ERROR Error seeding data: [AppwriteException: Invalid document structure: Missing required attribute &...
