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mysql建立季度和月的關(guān)聯(lián)表

MySQL關(guān)系型數(shù)據(jù)庫管理系統(tǒng)可用于創(chuàng)建季度和月的關(guān)聯(lián)表,以便排序和查詢數(shù)據(jù)。下面是一個(gè)示例,演示如何使用MySQL創(chuàng)建季度和月的關(guān)聯(lián)表。

CREATE TABLE quarters (
quarter_id INT PRIMARY KEY,
quarter_name VARCHAR(10)
);
CREATE TABLE months (
month_id INT PRIMARY KEY,
month_name VARCHAR(10)
);
INSERT INTO quarters (quarter_id, quarter_name) VALUES (1, 'Q1');
INSERT INTO quarters (quarter_id, quarter_name) VALUES (2, 'Q2');
INSERT INTO quarters (quarter_id, quarter_name) VALUES (3, 'Q3');
INSERT INTO quarters (quarter_id, quarter_name) VALUES (4, 'Q4');
INSERT INTO months (month_id, month_name) VALUES (1, 'January');
INSERT INTO months (month_id, month_name) VALUES (2, 'February');
INSERT INTO months (month_id, month_name) VALUES (3, 'March');
INSERT INTO months (month_id, month_name) VALUES (4, 'April');
INSERT INTO months (month_id, month_name) VALUES (5, 'May');
INSERT INTO months (month_id, month_name) VALUES (6, 'June');
INSERT INTO months (month_id, month_name) VALUES (7, 'July');
INSERT INTO months (month_id, month_name) VALUES (8, 'August');
INSERT INTO months (month_id, month_name) VALUES (9, 'September');
INSERT INTO months (month_id, month_name) VALUES (10, 'October');
INSERT INTO months (month_id, month_name) VALUES (11, 'November');
INSERT INTO months (month_id, month_name) VALUES (12, 'December');
CREATE TABLE quarter_month (
quarter_id INT,
month_id INT,
PRIMARY KEY (quarter_id, month_id)
);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (1, 1);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (1, 2);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (1, 3);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (2, 4);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (2, 5);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (2, 6);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (3, 7);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (3, 8);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (3, 9);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (4, 10);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (4, 11);
INSERT INTO quarter_month (quarter_id, month_id) VALUES (4, 12);

上述代碼中,"quarters"表用于存儲(chǔ)季度信息,包括季度ID和季度名稱。"months"表用于存儲(chǔ)月份信息,包括月份ID和月份名稱。"quarter_month"表用于建立季度和月份之間的關(guān)聯(lián)關(guān)系。

通過上述代碼,我們可以創(chuàng)建一個(gè)可以輕松排序和查詢數(shù)據(jù)的季度和月關(guān)聯(lián)表。