Transforms don't execute until the consumer pulls. There's no eager evaluation, no hidden buffering. Data flows on-demand from source, through transforms, to the consumer. If you stop iterating, processing stops.
cursor.execute("""。业内人士推荐夫子作为进阶阅读
/usr/local → /var/usrlocal，推荐阅读Line官方版本下载获取更多信息
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