Guides and cheat sheets

Short, practical references for the formats and query languages PasteKit works with.

• JSON vs YAMLJSON and YAML compared: syntax, data types, comments, anchors, parsing speed, security and the Norway problem, plus which one to choose for configs and APIs.
• TOML vs YAML for Configuration FilesTOML vs YAML for config files: syntax, typing, dates, nesting, null, tooling and real use in Cargo, pyproject and Kubernetes, with clear advice on choosing.
• JSON Lines (NDJSON) vs a JSON ArrayJSON Lines (JSONL, NDJSON) vs a regular JSON array: format rules, streaming, appending, logs, BigQuery and ML datasets, plus converting between them with jq.
• YAML Multiline Strings ExplainedEvery way to write a multiline string in YAML: literal |, folded >, chomping indicators - and +, indentation indicators, and quoted styles, with exact results.
• Comments in JSON: JSONC, JSON5 and Safe StrippingStandard JSON forbids comments. Learn how JSONC and JSON5 add them, which tools accept each, how to strip comments safely, and the conventions that avoid them.
• Big Integers in JSON and the 2^53 LimitWhy JSON.parse turns 9007199254740993 into 9007199254740992, which languages are affected, and how to keep 64-bit IDs exact with strings or lossless parsers.
• CSV Files and Excel: Encoding, BOM and DelimitersWhy Excel shows é instead of é, puts every CSV value in column A, or drops leading zeros — and how BOMs, Windows-1252, sep= lines and semicolon locales fix it.
• A Practical SQL Style GuideA practical SQL style guide: keyword case, one clause per line, comma placement, JOIN layout, aliases, CTEs, naming and comments, with the reason for each rule.
• jq Cheat SheetA compact jq reference: paths, iteration, select and map, building objects, updates, string functions, @csv output, reduce, variables and the most useful flags.
• JSONPath Cheat SheetJSONPath syntax at a glance: root, children, wildcards, recursive descent, slices, filters and RFC 9535 functions, plus differences between implementations.
• Cron Syntax Cheat SheetCron syntax reference: 5, 6 and 7 field formats, ranges, steps, @macros, the special characters L, W, # and ?, platform differences and ready-to-copy schedules.
• Regular Expression Cheat SheetRegex quick reference: character classes, anchors, quantifiers, groups, named captures, lookarounds, JavaScript flags, flavour differences and common patterns.
• JSON Schema BasicsLearn JSON Schema: types, properties and required, arrays, string and number rules, enum and const, combining schemas, $ref and $defs, and how drafts differ.
• Online Formatters and Leaked SecretsHow 80,000+ saved pastes on online formatters exposed credentials and keys in 2025, why client-side tools matter, and how to check for uploads in DevTools.
• JSON Patch (RFC 6902) and JSON Merge Patch (RFC 7396) ExplainedHow JSON Patch operations (add, remove, replace, move, copy, test) and JSON Merge Patch work, with examples, JSON Pointer paths, pitfalls and when to use which.
• How to Format Dates and Times in JSONJSON has no date type. Compare ISO 8601 and RFC 3339 strings with Unix seconds and milliseconds, handle time zones correctly, and avoid common parsing traps.
• Working with JSON in PythonPython json module explained: load vs loads, dump vs dumps, ensure_ascii, indent, default= for datetime and Decimal, parse_float, big integers and errors.
• JSON.parse and JSON.stringify: A Practical JavaScript GuideHow JSON.parse and JSON.stringify really behave: revivers, replacers, toJSON, undefined and NaN, BigInt, Dates, circular references, structuredClone and errors.
• JSON vs XMLJSON and XML compared on data model, schemas, querying, namespaces, mixed content, security and tooling, plus what goes wrong when converting between the two.