7.2 区间查找
SQL
SELECT *
FROM Orders
WHERE OrderDate>='2021-12-29' and OrderDate<='2021-12-31'
SPL
对于数值、日期类型的字段，常常会用到区间查找。凡是需要用到区间查找的字段，只能使用排序索引。
| A | |
|---|---|
| 1 | >st=date(“2021-12-29”), et=date(“2021-12-31”), start=days@o(st), end=days@o(et) |
| 2 | =file(“Orders.ctx”).open() |
| 3 | =A2.index(file(“Orders.ctx__OrderDate”);OrderDate) |
| 4 | =A2.icursor(;OrderDate>=start && OrderDate<=end; file(“Orders.ctx__OrderDate”)).fetch() |
| 5 | =A2.close() |
