使用 MySQL 中的存储过程创建明年的日历 table

Question

我需要使用 MySQL 中的存储过程创建明年的日历 table。

这段代码的问题是设置下一年的值，因为结果是

Procedure executed successfully
Affected rows: 0

这部分代码无法设置明年

'@tbl-01-01' + INTERVAL d.i * 1000 + c.i * 100 + a.i * 10 + b.i DAY AS date

如何在此过程中设置下一年变量？

有什么想法吗？

BEGIN

-- create a 2021 year
SET @tbl = DATE_FORMAT(DATE_ADD(CURDATE(), INTERVAL 1 YEAR),'%Y');

-- create a calendar table 2021
SET @s = CONCAT('DROP TABLE IF EXISTS tbl_calendar_', @tbl);
PREPARE stmt FROM @s;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

SET @s = CONCAT('CREATE TABLE IF NOT EXISTS tbl_calendar_', @tbl, ' LIKE tbl_calendar_2020');
PREPARE stmt FROM @s;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

-- create a ints table
DROP TABLE
IF EXISTS ints;

CREATE TABLE ints (i INTEGER);

INSERT INTO ints VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);

-- insert into calendar table 2021 from interval day
SET @s = CONCAT('INSERT INTO tbl_calendar_', @tbl, ' SELECT
    cal.date AS cdate,
    DAY (cal.date) AS cday,
    MONTH (cal.date) AS cmonth,
    YEAR (cal.date) AS cyear, 
    NULL
FROM
    (
        SELECT
            \'`@tbl`-01-01\' + INTERVAL d.i * 1000 + c.i * 100 + a.i * 10 + b.i DAY AS date
        FROM
            ints a
        JOIN ints b
        JOIN ints c
        JOIN ints d
        ORDER BY
            d.i * 1000 + c.i * 100 + a.i * 10 + b.i
    ) cal
WHERE
    cal.date BETWEEN \'`@tbl`-01-01\'
AND \'`@tbl`-12-31\'
ORDER BY
    cal.date ASC;');  

PREPARE stmt FROM @s;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

END

Answer 1

您可以像在 insert 子句中那样在 concat 函数中拆分字符串并在字符串外部添加变量。它看起来像这样：

SET @s = CONCAT('INSERT INTO tbl_calendar_', @tbl, ' SELECT
    cal.date AS cdate,
    DAY (cal.date) AS cday,
    MONTH (cal.date) AS cmonth,
    YEAR (cal.date) AS cyear, 
    NULL
FROM
    (
        SELECT \'',
            @tbl, '-01-01\' + INTERVAL d.i * 1000 + c.i * 100 + a.i * 10 + b.i DAY AS date
         ...'

每次在查询中使用@tbl 变量时，您都需要像这样在 concat 函数中拆分字符串。

使用 MySQL 中的存储过程创建明年的日历 table

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