CSV
Converting CSV to SQL INSERT Statements the Safe Way
Generate INSERT statements from a CSV without breaking on O'Neil or running a DROP TABLE hidden in a value. Batches of 1,000 loaded 193,708 rows in 1.6 s.
13 min read
Tag
conversion
49 posts
CSV
Converting JSON to CSV When the Data Is Nested With Arrays
Flatten nested JSON to CSV with pandas, Python or DuckDB: dotted columns, a row per array item, the order that vanishes and arrays written as Python text.
10 min read
CSV
Converting Excel to CSV Without Losing Leading Zeros
pandas turned a text cell 02134 into 2134 and in2csv did too; qsv kept it. A number formatted 00000 loses its zeros everywhere unless you rebuild them.
10 min read
CSV
Converting CSV to an Excel Workbook With Formatting
Write a CSV to .xlsx with xlsxwriter: text zips, number formats, real dates and a frozen header. write() made =1+1 a formula; rows past 1,048,575 vanished.
8 min read
CSV
Converting CSV to YAML for Config Seeds Without Surprises
Hand-written YAML turned NO into false, 02134 into 1116 and 12:30 into 750; yaml.safe_dump quotes them. Dumping 193,708 records took 53 s, 15 s with libyaml.
9 min read
CSV
Converting CSV to XML With a Short and Safe Python Script
Convert CSV to XML with the standard library: invalid tag names and control characters need your own checks; a streaming writer does 193,708 rows in 22 MB.
10 min read
CSV
Converting CSV to JSON Lines for Streaming Pipelines
Convert CSV to JSON Lines, one object per line: a 13 MB streaming script, DuckDB in 0.3 s, files that split cleanly and a cut-off file that shows itself.
9 min read
CSV
Converting CSV to JSON With Python Without Losing Types
Convert CSV to JSON with the csv module, then decide on types: zip stays text, money stays exact. pandas gave 2134.0 for 02134; converters took 0.4 to 36 s.
9 min read
CSVGuide
Converting CSV to JSON XML YAML and Excel in Practice
Convert one awkward CSV to JSON, JSON Lines, XML, YAML, Excel, Parquet, Markdown and SQL, read each back and see the cost on 193,708 rows.
22 min read
XML
Choosing Parquet After You Parse XML for Fast Analysis
A 132 MB XML file became 12.1 MB of Parquet. A grouped query ran in 19 ms against seconds of reparsing. How to write it, and when CSV or a database wins.
6 min read
Excel
Converting Google Sheets to CSV or Excel With a Script
Export a Google Sheet to CSV or xlsx from a script using the export URL, the Drive API or gspread, choose the sheet by gid and handle sharing and auth safely.
6 min read
Excel
Converting Excel to Markdown and HTML Tables for Docs
Turn a worksheet into a Markdown or HTML table for documentation with pandas, escape pipes and line breaks, align numbers and keep wide tables readable.
6 min read