Excel
Formula Injection in Excel Exports and How to Stop It
Stop formula injection in xlsx exports: write user text as strings with openpyxl or XlsxWriter, neutralize leading =, +, - and @ characters, and test it.
7 min read
Tag
how-to
590 posts
XML
When XML Attributes Are the Better Choice Over Elements
Attributes suit short identifying values, elements suit everything with structure or long text. A test of the whitespace and ordering rules shows why.
6 min read
CSV
Reading a CSV File in PHP With fgetcsv and SplFileObject
Read CSV in PHP 8.5 with fgetcsv and SplFileObject: the $escape deprecation, a backslash that swallows the file, str_getcsv traps and the BOM.
10 min read
JSON
Flattening Nested JSON With LATERAL FLATTEN in Snowflake
Use FLATTEN in Snowflake to turn VARIANT arrays and objects into rows, chain it for nested levels, keep empty parents with OUTER, and read its output columns.
6 min read
CSV
Reading a CSV File in C Sharp With CsvHelper Correctly
Read CSV in C# with CsvHelper 33: case-sensitive headers, typed ZIP codes, silent ragged rows, and a de-DE culture that made a total 91 times too big.
10 min read
Excel
Converting Excel to CSV for Every Sheet in a Workbook
Export every sheet of an Excel workbook to its own CSV with pandas, openpyxl or LibreOffice, with safe file names, UTF-8, ISO dates and a manifest.
8 min read
CSV
Parsing CSV in Rust With the csv Crate and Serde Types
Parse CSV in Rust with the csv crate: StringRecord, ByteRecord and serde, UnequalLengths errors, typed ZIP codes and an unclosed quote it accepts.
9 min read
JSON
Querying VARIANT Columns With Colon Syntax in Snowflake
Read JSON stored in a Snowflake VARIANT column with colon and bracket paths, cast the results, and handle JSON null, missing keys and case sensitivity.
7 min read
CSV
Reading CSV Files in R With readr and fread Safely
Compare read_csv, fread and base read.csv on the same files: type guessing and ZIP codes, ragged rows, bad quotes, the BOM, and speed on 2,000,000 rows.
10 min read
ExcelGuide
Converting Excel to CSV JSON XML and YAML in Practice
Convert Excel workbooks to CSV, JSON, XML and YAML without losing data: choose a format, read types, dates and headers, then verify with counts and schemas.
17 min read
CSV
Reading a CSV File in Java With OpenCSV and Commons CSV
Read CSV in Java with OpenCSV and Commons CSV: a backslash escape that breaks paths, ints that turn blanks into 0, and a writer that quotes everything.
10 min read
XMLGuide
Comparing and Versioning XML Files in Git and in Pipelines
A tested guide to comparing XML, from canonical form and keyed record diffs to Git diffs, merges, feed shape checks and schema compatibility.
18 min read