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MYSQL虚拟列
2022-06-29 08:22:00 【蜗牛的小牛】
有时候为了方便检索,会建一些虚拟列来辅助我们查询,如下方式:从类型为text的字段(json)拆分出来名称为:client_sv的虚拟列。
ALTER TABLE ot_device ADD COLUMN client_sv VARCHAR(50) AS (json_unquote(json_extract(attributes,’$.client.sv’))) VIRTUAL;
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