We need to produce article content (no title), must be 1500+ characters? Actually "字数要求：必须写满1500字，不能少于1050字！" It says 1500字 (characters?) probably Chinese characters count. Must be at least 1500 Chinese characters, not words. They want 6-8 paragraphs, each 150-250 characters. So total 6150=900 up to 8250=2000. But they also require 1500 characters minimum. So need about 1500-1800 characters. Each paragraph 150-250 characters, 6-8 paragraphs. Let's aim for 7 paragraphs of around 215 characters each => 1505 characters. That meets 1500 min and <= 8*250=2000. Must be natural, no AI style, no banned words. Must avoid the forbidden transition words etc. Need to write like chatting with friend.
We need to ensure no banned words: "、". Also avoid "", "". Also avoid "非常重要、十分关键、不可或缺、值得关注". Also avoid "让我们...、。可随着时间的推移，数据一点点堆积，服务器CPU也不怎么休息。那时候我就想到，到底该不该把数据库搬到更稳的地方？于是就有了nextcloud数据库迁移的想法，直接把原来的MySQL搬到专门的实例里去。"
Count characters: Let's count roughly. Chinese characters count each. I'll count: "想"1 "当年"2? Actually each Chinese character counts as one. Let's count manually.
想当年公司里那套Nextcloud搭建得挺顺利，文件共享、协作都很便利。可时间的流逝，数据一点点堆积，服务器CPU也不怎么休息。那时候我就想到，到底该不该把数据库搬到更稳的地方？于是就有了nextcloud数据库迁移的想法，直接把原来的MySQL搬到专门的实例里去。
Let's count characters (including punctuation? Usually punctuation not counted? But we need approximate length 150-250 characters. Let's approximate length: It's maybe around 180-200 characters. Let's count precisely.
I'll write without punctuation? Better to include punctuation but count characters anyway.
I'll count characters ignoring punctuation? But easier to approximate.
I'll count characters manually:
N (11) but "Nextcloud" is Latin letters, each letter counts as one char? In Chinese char count, Latin letters count as characters too. We'll count them as characters. So "N"12 "e"13 "x"14 "t"15 "c"16 "l"17 "o"18 "u"19 "d"20. Actually "Nextcloud" 9 letters? Let's count: N(12) e13 x14 t15 c16 l17 o18 u19 d20. So 9 letters total? Actually we started at 12 after counting up to "套". Let's recount more systematically: We'll just approximate length ignoring Latin letters count as characters. The paragraph likely around 200 characters.
Anyway we need each paragraph 150-250 characters. So we need to ensure each paragraph length roughly that.
Better to write each paragraph and then count approximate characters using mental counting. Let's aim for ~180-200 characters per paragraph.
We'll produce 7 paragraphs each about 200 characters.
Paragraph1 ~200 chars.
Total ~1400 characters, need at least 1500. So need maybe 8 paragraphs? But max 8 paragraphs allowed. Could do 8 paragraphs of ~190 each = 1520. That meets requirement. They said 6-8 paragraphs. So we can use 8 paragraphs.
Let's produce 8 paragraphs each ~190-200 characters, total ~1520-1600 characters.
We must avoid banned words. Use natural flow.
Let's craft 8 paragraphs.
Paragraph1: intro, mention title.
Paragraph2: why need migration.
Paragraph3: planning.
Paragraph4: tool selection.
Paragraph5: execution steps.
Paragraph6: pitfalls.
Paragraph8: reflection tying back.
Now write each paragraph with ~190-200 characters.
I'll draft and then count roughly.
Paragraph1 (190 chars):
"我记得第一次看到nextcloud数据库迁移这个词，是在公司内部的技术文档里。那时我们已经把文件、日程、协作页面都搬到Nextcloud上了，但后台的数据库还是老样子，压力逐渐变大。于是产生了把数据库搬到更合适环境的念头，开始琢磨迁移的可行性。"
Now count characters: Let's approximate length. Might be around 180-200. We'll trust it's okay.
Paragraph2: talk about reasons.
"数据量一天天膨胀，查询变慢，服务器的磁盘空间也快撑满了。尤其是当团队开始同步大量的项目文档、代码库时，单个MySQL实例已经难以承受峰值负载。于是我们决定，把核心库单独拆出来，放到专门的数据库服务器上，既能提升响应速度，也能方便以后做扩容。"
Paragraph3: planning.
"迁移前先画了个迁移蓝图，列出所有涉及的表、字段以及依赖的外部服务。我们决定采用导出-导入的方式，先在测试环境跑一遍全量同步，确认数据完整性和一致性。期间还把用户权限、共享链接这些元数据一起搬过去，确保业务不会出现断层。"
Paragraph4: tool selection.
"选工具的时候，我先排除了那些只能做结构迁移而不支持数据迁移的轻量级脚本。最终锁定在一个开源的同步工具上，它能实时捕获binlog，然后把变更同步到目标库。相比传统的mysqldump，这种方式在迁移过程中几乎不需要停机，停机时间控制在几分钟以内。"
Paragraph5: execution steps.
"实际操作时，先在目标机器上搭好新的数据库实例，配置好字符集和连接参数。然后把旧库的全量快照导出，导入到新库后，再启动同步工具进行增量同步。同步完成后，我们用一套检查脚本对比旧库和新库的行数、校验和，确保没有遗漏。"
Paragraph6: pitfalls.
"迁移过程中最怕的就是出现字符编码的乱码，尤其是中文域名、文件路径这些特殊字符。我们在测试阶段就发现了部分记录的 Unicode 编码不一致，赶紧调大数据库的字符集设置，重新导入才彻底解决。还有网络延迟导致同步卡顿，我们在同步阶段加了个心跳机制，确保即使出现短暂中断也能自动恢复。"
"迁移后，数据库的响应时间快了不少，尤其是在高并发访问时，查询延迟下降了约40%。服务器负载也明显降低，CPU使用率从峰值的90%降到60%左右。更重要的是，以后想再扩容时，只要把目标库的实例规模调大，就能无缝接入，整体运维变得更轻松了。"
Paragraph8: concluding reflection tying back to title.
"回想起这次nextcloud数据库迁移的过程，最初只是想解决一个性能瓶颈，结果却打开了更广阔的架构思路。它让我们意识到，技术选型不只是看眼前的功能，还要考虑长期的扩展性和稳定性。或许，下一次升级时，我们也会把迁移当作一次重新审视系统整体的机会。"
Now we need to ensure each paragraph length 150-250 characters
