SQL查询根据不同的条件获取计数

Question

表格列的说明 -

TYPE：VARCHAR

STATUS：VARCHAR

ORDER_DATE：TIMESTAMP WITH TIMEZONE

请查看下表结构和所需输出。

在所需的结果中 -

0TO30DAYS：过去30天的类型计数

30TO60DAYS：之前31到60天的类型计数

60TO90DAYS：61至90天的类型计数

请注意，我使用Oracle DB无法根据不同的日期范围创建三个不同的计数列。请告诉我如何在ORACLE中为此创建SQL。

Answer 1

count会忽略null，因此您可以使用您的逻辑count case表达式：

SELECT   type,
         COUNT(CASE WHEN day_diff BETWEEN 0 AND 31 THEN 1 ELSE NULL END) 
           AS "0TO30DAYS",
         COUNT(CASE WHEN day_diff BETWEEN 31 AND 61 THEN 1 ELSE NULL END) 
           AS "30TO60DAYS",
         COUNT(CASE WHEN day_diff BETWEEN 61 AND 91 THEN 1 ELSE NULL END) 
           AS "60TO90DAYS"
FROM     (SELECT type, CAST (order_date AS DATE) - SYSDATE AS day_diff
          FROM   my_table)
GROUP BY type

Answer 2

SELECT TYPE,
       CASE
         WHEN order_date >= (SYSDATE - 30) AND order_date < SYSDATE THEN
          COUNT(TYPE)
       END AS count30,
       CASE
         WHEN order_date >= (SYSDATE - 60) AND order_date < (SYSDATE - 30) THEN
          COUNT(TYPE)
       END AS count60,
       CASE
         WHEN order_date >= (SYSDATE - 90) AND order_date < (SYSDATE - 60) THEN
          COUNT(TYPE)
       END AS count90
  FROM TABLE
 GROUP BY TYPE, order_date