如何使用 NOW() 函数作为范围的上限？
How to use the NOW() function as upper bound of a range?
我在 Postgres 10.6 数据库中有一个 table，其中有一列类型为 tstzrange。
我需要插入/更新具有已定义下限的行，但当前时间的值是范围的上限，因此 NOW() 作为上限值。
尝试过类似的东西：
UPDATE table_name
SET date_range = ['2018-03-23 00:00:00-05', now())
WHERE id = 3;
有没有办法使用内置函数或子查询？
使用范围构造器。 The manual:
Each range type has a constructor function with the same name as the
range type. Using the constructor function is frequently more
convenient than writing a range literal constant, since it avoids the
need for extra quoting of the bound values. The constructor function
accepts two or three arguments. The two-argument form constructs a
range in standard form (lower bound inclusive, upper bound exclusive),
while the three-argument form constructs a range with bounds of the
form specified by the third argument. The third argument must be one
of the strings “()”, “(]”, “[)”, or “[]”.
所以：
UPDATE table_name
SET date_range = tstzrange('2018-03-23 00:00:00-05', now())
WHERE id = 3;
我假设您知道 now() 解析为事务的开始时间。
我在 Postgres 10.6 数据库中有一个 table，其中有一列类型为 tstzrange。
我需要插入/更新具有已定义下限的行，但当前时间的值是范围的上限，因此 NOW() 作为上限值。
尝试过类似的东西：
UPDATE table_name
SET date_range = ['2018-03-23 00:00:00-05', now())
WHERE id = 3;
有没有办法使用内置函数或子查询？
使用范围构造器。 The manual:
Each range type has a constructor function with the same name as the range type. Using the constructor function is frequently more convenient than writing a range literal constant, since it avoids the need for extra quoting of the bound values. The constructor function accepts two or three arguments. The two-argument form constructs a range in standard form (lower bound inclusive, upper bound exclusive), while the three-argument form constructs a range with bounds of the form specified by the third argument. The third argument must be one of the strings “
()”, “(]”, “[)”, or “[]”.
所以：
UPDATE table_name
SET date_range = tstzrange('2018-03-23 00:00:00-05', now())
WHERE id = 3;
我假设您知道 now() 解析为事务的开始时间。