JSON
Using DynamoDB Maps and Lists as JSON Documents Safely
Store JSON in DynamoDB map and list attributes, update nested paths in place and avoid float, reserved-word and size errors, tested on DynamoDB Local.
7 min read
Library
Everything you need to level up your coding skills.
Excel
Zip Bombs and Oversized XLSX Uploads and Limits That Work
Stop zip bombs and oversized xlsx uploads with limits on file size, entry count, expansion ratio and rows, enforced before parsing and sized from real files.
7 min read
CSV
Removing Duplicate Rows From a CSV and Choosing the Keeper
Deduplicating a CSV is easy; deciding which duplicate to keep is not. Compare first, last, latest-signup and highest-balance keepers on 200,000 rows.
9 min read
XML
Embedding Binary Data in XML With Base64 and When Not To
XML cannot hold raw bytes. Base64 adds 33 percent, hex adds 100 percent, and both cost memory. Measured sizes, the schema type, and the alternatives.
6 min read
CSV
Trimming Whitespace in Every Field of a CSV Safely
Trim padded CSV fields with pandas, the csv module, DuckDB and qsv, and see why strip() misses the zero-width space that still breaks an email match.
9 min read
Excel
Opening Untrusted Excel Files Safely in a Pipeline
Open untrusted Excel files in a sandboxed worker with no network, memory and time limits, a read-only parser and no desktop Excel, then load results as data.
7 min read
JSON
Storing JSON in ClickHouse and Querying Its Fields Fast
Store JSON in ClickHouse as a String with JSONExtract functions or as the native JSON type, with size and speed measured on 200,000 documents.
7 min read
Editor's pick
CSVGuide
A Repeatable Way to Clean a Messy CSV File With Python
A cleaning pipeline that never edits the raw file, counts rows at every step and keeps rejects: 200,000 rows in 3.85 s, identical output twice.
25 min read
YAML
Safe Loaders in Python Ruby and Java Compared and Tested
Which function to call in PyYAML, Ruby Psych and SnakeYAML to load untrusted YAML safely, what each default does and how to grep for the unsafe ones.
6 min read
Excel
Removing Personal Data From an Excel File Before Sharing
Remove personal data from an Excel file before sharing: drop author properties, mask or delete columns, clear comments and rebuild a clean copy by script.
7 min read
XML
Modeling Lists and Optional Data in XML Without Surprises
Wrapper elements, empty versus absent versus nil, and the one-item list trap when XML becomes JSON, all demonstrated with real parser output.
6 min read
CSV
Reading a CSV in Swift on macOS and the CRLF Line Trap
Swift has no CSV parser in Foundation, and its String treats CRLF as one Character, so splitting on a newline fails. Parse bytes or use SwiftCSV.
9 min read
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