sqlite - 如何将字符串数组插入sqlite3表的列

Question

如何创建可以将字符串数组作为列值保存的表。例如。：

CREATE TABLE bug
(
    id BIGINT NOT NULL,
    title VARCHAR,
    description VARCHAR,
    timestamp TIMESTAMP,
    duedate DATETIME,
    assignedto VARCHAR,
    userid BIGINT NOT NULL,
    viewedby VARCHAR[],
    watchers VARCHAR[],
    priority VARCHAR,
    tags VARCHAR[],
    comments VARCHAR[],
    PRIMARY KEY(id)
    FOREIGN KEY(userid) REFERENCES user(id)
);

以及在插入数据时如何在此字段中插入值。

Answer 1

通常情况下，您不会那样降低可用性（即无法轻易辨别第n个元素）。

而是可以创建一个表，该表的每个元素都有一列，并具有指向各个错误的链接/引用/映射。

例如您可能会遇到以下情况：-

DROP TABLE If EXISTS bug;
DROP TABLE IF EXISTS bugarrayelements;
CREATE TABLE IF NOT EXISTS bug
(
    id BIGINT NOT NULL,
    title VARCHAR,
    description VARCHAR,
    timestamp TIMESTAMP,
    duedate DATETIME,
    assignedto VARCHAR,
    userid BIGINT NOT NULL,
    viewedby VARCHAR[],
    watchers VARCHAR[],
    priority VARCHAR,
    tags VARCHAR[],
    comments VARCHAR[],
    PRIMARY KEY(id)
    --FOREIGN KEY(userid) REFERENCES user(id) -- commented out for convenience
);
CREATE TABLE IF NOT EXISTS bugarrayelements
(bug_reference INTEGER, element_order INTEGER, element_data TEXT
);

-- First bug with representation of a 5 element string array
INSERT INTO bug (id,title,userid) VALUES(1,'bug001',100);
INSERT INTO bugarrayelements VALUES 
    (1,1,'This failed.'),
    (1,2,'It failed with this error.'),
    (1,3,'It failed on line 2450.'),
    (1,4,'Out of a total of 9567 lines of code.'),
    (1,5,'blah blah blah.')
;

-- Second bug
INSERT INTO bug (id,title,userid) VALUES(2,'bug500',321);
INSERT INTO bugarrayelements VALUES
    (2,1,'This failed.'),
    (2,2,'It failed with this error.'),
    (2,3,'It failed on line 2450'),
    (2,4,'Out of a total of 9567 lines of code.'),
    (2,5,'blah blah blah.'),
    (2,1,'This failed.'),
    (2,2,'It failed with this error.'),
    (2,3,'It failed on line 2450'),
    (2,4,'Out of a total of 9567 lines of code.'),
    (2,5,'blah blah blah.')
;
SELECT * FROM bug JOIN bugarrayelements ON bug_reference = bug.id ORDER BY bug.id,element_order;
SELECT bug.title,bug.userid, group_concat(element_data,' ~~~ ') FROM bug JOIN bugarrayelements ON bug_reference = bug.id GROUP BY bug.id ORDER BY bug.id, element_order;

使用上面的第一个结果将是：-



第二个结果是：



上面显示了多个插入（即所有数组元素），它们也可以单独添加（可能在事务中）