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法律研究如何在 MySQL 视图的帮助下从日期范围内生成天数？
为了说明这一点，我们创建以下视图 −
mysql> CREATE VIEW digits AS -> SELECT 0 AS digit UNION ALL -> SELECT 1 UNION ALL -> SELECT 2 UNION ALL -> SELECT 3 UNION ALL -> SELECT 4 UNION ALL -> SELECT 5 UNION ALL -> SELECT 6 UNION ALL -> SELECT 7 UNION ALL -> SELECT 8 UNION ALL -> SELECT 9; Query OK, 0 rows affected (0.08 sec) mysql> CREATE VIEW numbers AS SELECT ones.digit + tens.digit * 10 + hundreds.digit * 100 + thousands.digit * 1000 AS number FROM digits as ones, digits as tens, digits as hundreds, digits as thousands; Query OK, 0 rows affected (0.09 sec) mysql> CREATE VIEW dates1 AS SELECT SUBDATE(CURRENT_DATE(), number) AS date FROM numbers UNION ALL SELECT ADDDATE(CURRENT_DATE(), number + 1) AS date FROM numbers; Query OK, 0 rows affected (0.09 sec) mysql> Select date from dates1 where date between '2017-11-15' and '2017-11-30'order by date; +------------+ | date | +------------+ | 2017-11-15 | | 2017-11-16 | | 2017-11-17 | | 2017-11-18 | | 2017-11-19 | | 2017-11-20 | | 2017-11-21 | | 2017-11-22 | | 2017-11-23 | | 2017-11-24 | | 2017-11-25 | | 2017-11-26 | | 2017-11-27 | | 2017-11-28 | | 2017-11-29 | | 2017-11-30 | +------------+ 16 rows in set (0.05 sec)
更新于:22-Jun-2020
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