AI English Listening
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Topics
Section titled “Topics”English Exercise
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Reading
Read 101 Conversations and Harry Potter with vocabulary support. Browse Reading.
Media
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Others
Review useful English sentences grouped by everyday topics. Browse Others.
Peppa Pig
Study everyday English vocabulary and sentences episode by episode. Browse Peppa Pig.
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社交关系天然是一张图：A 认识 B，B 认识 C，则 A 与 C 虽无直接边，也同属一个圈子。把「能通过认识关系串起来的人」收成一组，本质就是无向图上的连通分量（Connected Components）。 本文用同一套样例数据，对比三种在 DuckDB 内落地的做法：纯 SQL 递归合并、Onager 连通分量、DuckPGQ 弱连通分量。 业务场景…
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官方DOC struct and unnest recursive unnest RECURSIVE split write csv read csv read text xlsx write xlsx read xlsx create table insert into recursive query regexpmatche date/time…
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