Editor's pick
CSVGuide
Reading and Writing CSV Files in Python the Right Way
A working guide to CSV in Python: csv module, DictReader, pandas, polars and DuckDB measured on 2,000,000 rows, plus the encoding, quoting and type rules.
22 min read
Topic
Scripting
Shell one-liners and small scripts that turn your repeated database chores into a single command.
CSV
Turning a Folder of CSV Files Into a SQLite Database
One table per CSV file, with safe names and types inferred from the whole file. A short Python script that keeps ZIP codes as text and refuses ragged files.
9 min read
CSV
Loading Many CSV Files Into One SQLite Database in Bash
A bash loop that imports monthly CSV files into one SQLite table, records which file each row came from, and refuses to load a file twice.
7 min read
YAMLGuide
Working With YAML From the Terminal Using yq and Friends
A tested command-line guide to YAML: query, edit, merge, convert, lint, validate and diff with yq, yamllint and check-jsonschema, plus the traps found.
20 min read
YAMLGuide
Reading and Writing YAML in Python Safely and Cleanly
A tested Python guide to YAML: safe loading, speed, strict keys, validation, clean output, round trips, merging, env substitution and a reference module.
20 min read
ExcelGuide
Reading and Writing Excel Files With openpyxl in Python
A working guide to openpyxl: the workbook model, reading values and formulas, writing and editing files, large-file modes, styles, charts and errors.
19 min read
XMLGuide
Parsing and Writing XML in Python With ElementTree and lxml
A tested guide to XML in Python: ElementTree versus lxml, reading, streaming, writing, namespaces, validation, XSLT, tables, safety and an end-to-end script.
18 min read
JSON
Fixing JSON That Is Really a JavaScript Object Literal
Text copied from console.log, DevTools or a config file is often a JavaScript object, not JSON. What differs, what is lost, and how to convert it safely.
7 min read
JSON
Python JSONDecodeError Extra Data and Concatenated Objects
Extra data means a valid JSON value was followed by more text. Why concatenated objects and JSON Lines trigger it and three ways to read them in Python.
7 min read
JSON
Python JSONDecodeError Expecting Value Line 1 Column 1
Why json.loads or response.json() raises Expecting value at line 1 column 1 in Python, how to see what the text really is, and a checklist for each cause.
7 min read
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