Read a PostgreSQL EXPLAIN plan before adding an index
Find the expensive step and distinguish estimates from measurements.
PostgreSQL / SQL / Performance
TECHNOLOGY / KNOWLEDGE / PRACTICE
Search results: AI
Practical guides to AI, Python, Git, SQL, Web/API, SAP/ERP and mathematical models, with explanations, code examples, sources and limitations.
Every word must appear in the article. Use quotes for an exact phrase.
Git merge or rebase: choose by how the branch is shared
Preserve shared history or replay local work before integration.
Git / Merge / Rebase
401, 403, 429 or 503: where to start with an API error
Separate authentication, permissions, rate limits and service availability before retrying.
HTTP / API / Troubleshooting
Python: Reading JSON from Strings and Files, and Handling Decoding Errors
Learn how to parse JSON data in Python from both string literals and files, and how to effectively handle potential decoding errors using the built-in `json` module.
python / json / parsing / decoding / file handling / error handling / pathlib / data serialization
Create a Python virtual environment without mixing dependencies
A small, repeatable setup for a project and a quick check that pip uses the right Python.
Python / venv / pip
What RAG changes—and what it does not
How retrieval connects a language model to documents, and why a citation is not a guarantee.
AI / RAG / Retrieval
SAP FI and CO: two views of the same transaction
Understand financial reporting, internal cost allocation and their connection in S/4HANA.
SAP / FI / CO / S/4HANA
Why SQL comparisons with NULL do not behave like zero
Understand IS NULL, three-valued logic and the difference between COUNT(*) and COUNT(column).
SQL / PostgreSQL / NULL
Validate a time-series forecast without leaking the future
Use chronological splits and fit preprocessing only on past data.
Python / Time series / Validation