SequoiaDB 简介 
安装部署
数据库实例
分布式引擎
SAC 管控中心
参考手册
常见问题及解答（FAQ）
版本信息
SequoiaDB 巨杉数据库中 SQL 语句可以嵌套子句进行数据库操作，支持的子句如下：
| 语句 | 描述 | 示例 |
|---|---|---|
| where | 过滤记录 | db.exec("select * from sample.employee where age > 10") |
| group by | 对结果集进行分组 | db.exec("select dept_no, count(emp_no) as 员工总数 from sample.employee group by dept_no") |
| order by | 对结果集排序 | db.exec( "select dept_no,count(emp_no) as 员工总数 from sample.employee group by dept_no order by dept_no desc" ) |
| split by | 拆分记录 | db.exec( "select a,b,c from sample.employee split by c" ) |
| limit | 限制返回的记录个数 | db.exec("select * from sample.employee limit 2") |
| offset | 设置跳过的记录数量 | db.exec("select * from sample.employee offset 3") |
| as | 为集合名、字段名或结果集指定别名 | db.exec("select age as 年龄 from sample.employee where age>10") |
| inner join | 内连接 | db.exec( "select T1.a, T2.b from sample.employee1 as T1 inner join sample.employee2 as T2 on T1.a < 10" ) |
| left outer join | 左连接 | db.exec("select t1.LastName, t1.FirstName, t2.OrderNo from sample.persons as t1 left outer join sample.orders as t2 on t1.Id_P=t2.Id_P") |
| right outer join | 右链接 | db.exec("select t1.LastName, t1.FirstName, t2.OrderNo from sample.persons as t1 right outer join sample.orders as t2 on t1.Id_P=t2.Id_P") |
| hint | 显式地控制执行方式或者执行计划 | db.exec("select * from sample.employee1 where a = 1 /*+use_index(idx_employee1_a)*/") |
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