在 SQL 中,可以使用以下几种实用技巧来获取周数:
DATE_FORMAT()
函数(适用于 MySQL):SELECT DATE_FORMAT(your_date, '%W') AS week_number
FROM your_table;
WEEK()
函数(适用于 MySQL):SELECT WEEK(your_date) AS week_number
FROM your_table;
DATE_PART()
函数(适用于 PostgreSQL):SELECT DATE_PART('week', your_date) AS week_number
FROM your_table;
EXTRACT()
函数(适用于 PostgreSQL):SELECT EXTRACT(WEEK FROM your_date) AS week_number
FROM your_table;
ISOWEEK()
函数(适用于 SQL Server):SELECT ISOWEEK(your_date) AS week_number
FROM your_table;
TRUNC()
和 TO_CHAR()
函数(适用于 Oracle):SELECT TO_CHAR(TRUNC(your_date, 'WW'), 'WW') AS week_number
FROM your_table;
请将 your_date
和 your_table
替换为实际的日期字段和表名。这些函数将帮助您获取日期所在周的周数。