如何從 SQL 選擇中獲取 JSON 數組

Question

我想在我的 SQL 選擇中獲取一組對象。

SELECT id, a.name antibodyName, c.name colorName, c.location colorLocation 
FROM Antibodies a 
JOIN AssignedColors c ON id = antiId 
WHERE colorId IS NOT NULL

我得到這個回應：

[
  { id: 1, antibodyName: 'antibody 1', colorName: 'red', colorLocation: 'A5/C3' },
  { id: 2, antibodyName: 'antibody 2', colorName: 'red', colorLocation: 'C3/A1' },
  { id: 2, antibodyName: 'antibody 2', colorName: 'yellow', colorLocation: 'E4/F2' }
]

有可能得到這樣的東西嗎？

[
  { id: 1, antibodyName: 'antibody 1', colors: [{name: 'red, location: 'A5/C3'}] },
  { id: 2, antibodyName: 'antibody 2', colors: [{name: 'red, location: 'C3/A1'}, {name: 'yellow', location: 'E4/F2'}] },
]

Answer 1

使用 json_build_object 和 array_agg。

WITH foobar AS ( 
    SELECT id, a.name antibodyName, c.name colorName, c.location colorLocation 
    FROM Antibodies a JOIN AssignedColors c
    ON id = antiId WHERE colorId IS NOT NULL
    )
SELECT 
     json_build_object('data',array_agg(json_build_object('id', id, 'antibodyName', antibodyName, 'colorName', colorName, 'colorLocation', colorLocation))
FROM 
    foobar

Answer 2

有點生疏，但試試這個：

SELECT
a.id AS 'Id',
a.Name AS 'antibodyName',
c.Name AS 'name',
c.location AS 'location'
FROM Antibodies a
LEFT JOIN AssignedColors c ON c.id = a.Id
FOR JSON AUTO;

更新：以上不適用於 SQLite。 對於 SQLite，您應該在此處查看 json1 擴展： https ://www.sqlite.org/json1.html

另一個更新：它可以在沒有 JSON 擴展的情況下完成......

SELECT
a.id AS 'id',
a.Name AS 'antibodyName',
(SELECT '[' || GROUP_CONCAT('{name:"' || Name || '", location:"' || location || '"}') ||']'
 FROM AssignedColors
 WHERE c.id=Id) AS colors
 FROM Antibodies a
 LEFT JOIN AssignedColors c ON c.id = a.id
 GROUP BY a.id

這里有一個小問題：顏色列/節點被視為字符串而不是數組......這是正常的，因為 sqlite 不支持數組類型的列。 需要進行一些解析才能從字符串轉換為數組...