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解决方法数据库的sequence满足不了我们的要求，需要借助序号表来实现必须自己建一个表xxx_seq(year int, currval int, …)得到currval 之前检查是否有当年的记录，若无，则插入一条新的记录，year为当年记录，currval为1。若有则加1更新并查出来。...

Sql查询某个字段在数据库哪个表Mysql写法SELECT table_schema,table_name,column_name FROM information_schema.columns WHERE table_schema = 'xxx' AND TABLE_NAME LIKE '%xxx%' AND column_name LIKE '%xxx%'...

各个部门工资最高的前N个员工Oracle写法SELECT department_id, first_name, last_name, salaryFROM( SELECT department_id, first_name, last_name, salary, ROW_NUMBER() OVER (PARTITION BY department_id ORDE...