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Mysql报错:too many connections原因及解决方法 1、原因是mysql连接数过多 解决方案: 1、linux登录mysql: mysql -u root -p; 2、查看mysql允许的最大连接数 show variables like '%max_connections%'; 阅读全文
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SQL执行顺序,优化的禁止项建议项 SQL执行顺序如下: 1 .FROM,(-including JOIN ) 2. WHERE 3. GROUP BY 4. HAVING 5. WINDOW functions 6. SELECT 7. DISTINCT 8. UNION 9. ORDER BY 阅读全文
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1.sqlsugar 增删改查 demo entity query: var getAll = db.Queryable().ToList(); var getAll2 = db.Queryable().Select(x => x.CreateTime.Date).ToList(); var get 阅读全文