https://dailypypy.org/tags/list/ Recent content in List on 每日拍拍 Hugo -- gohugo.io zh-tw © 2026 每日拍拍 Thu, 15 Oct 2026 12:33:00 +0800 155076163427069952 154825760438254592 https://dailypypy.org/learn/polars-nested-json-ndjson/ Thu, 15 Oct 2026 12:33:00 +0800 https://dailypypy.org/learn/polars-nested-json-ndjson/ <!--- 1440x768 prompt: masterpiece, best quality, highres, clean anime illustration, japanese anime style, soft shading, flat color design, 1girl, black hair, green eyes, white off-shoulder shirt, black short skirt, eye-level three-quarter full body view, holding an open blank book with both hands, thoughtful gentle smile, looking at viewer, pastel pistachio and soft blush background, subtle nested translucent rounded frames beside her without symbols, logos, markings, numbers, letters, or text, neat composition, detailed eyes, cute and smart vibe, minimal background, polished illustration, no text negative prompt: worst quality, bad eye, bad hand, extra limbs, manga, multiple views, monochrome, text, signature dedup note: Specific follow-up to ../python-polars/ and ../polars-lazyframe-query-optimization/. This article focuses nested NDJSON admission, explicit Struct/List schemas, field namespaces, list-local expressions, explode grain/cardinality and null/empty semantics, schema drift quarantine and provenance. It does not repeat general expressions, optimizer benchmarks, time windows, or ../python-json/ serialization hooks. The planned Textual Modes topic was already published; Friday's absent slug passed a fresh 191-post current-source preflight before drafting. source check: Official Polars scan_ndjson/read_ndjson and Struct/List guides reviewed 2026-10-15; runnable examples tested with Polars 2.0.0. Explicit explode flags avoid relying on version-dependent empty-list defaults. The publication timestamp permits the morning deployment while retaining the requested randomized display date. ---> <h2 class="relative group">一. 前言：API 回來的不是一張表 <div id="一-前言api-回來的不是一張表" class="anchor"></div> <span class="absolute top-0 w-6 transition-opacity opacity-0 ltr:-left-6 rtl:-right-6 not-prose group-hover:opacity-100"> <a class="group-hover:text-primary-300 dark:group-hover:text-neutral-700" style="text-decoration-line: none !important;" href="#%e4%b8%80-%e5%89%8d%e8%a8%80api-%e5%9b%9e%e4%be%86%e7%9a%84%e4%b8%8d%e6%98%af%e4%b8%80%e5%bc%b5%e8%a1%a8" aria-label="定位點">#</a> </span> </h2> <p>嗨，我是拍拍君。今天收到一份訂單匯出： 每筆訂單有客戶物件，客戶裡有國家，訂單裡還有商品清單。 把 JSON 讀進來不難，難的是「一列到底代表什麼」。</p>