发出简单数组的 SQL FOR JSON

Question

使用 MS SQL Server 2017，我有 2 个表：

• 贷款：列包括贷款、组织ID
• 组织：列包括组织 ID

我的目标是生成 JSON，其中包含一个包含组织贷款编号的字符串数组。

我在这些方面使用 SQL：

SELECT
    OrganizationID,
    (   SELECT '[' + STRING_AGG('''' + Loan + '''', ',') + ']' 
        FROM Loan 
        WHERE Loan.OrganizationID = Organization.OrganizationID
    ) AS [Loans]
FROM Organization 
WHERE OrganizationID = 1
FOR JSON PATH, WITHOUT_ARRAY_WRAPPER;

我想得到这个：

{
    "OrganizationID": 1,
    "Loans": ['Test 001','Test Loan 123','Test Loan 234']
}

然而，我实际得到的用引号包裹了 Loans 值：

{
    "OrganizationID": 1,
    "Loans": "['Test 001','Test Loan 123','Test Loan 234']"
}

我意识到我可以这样做：

{
    "OrganizationID": 1,
    "Loans": ['Test 001','Test Loan 123','Test Loan 234']
}

产生这个：

{
    "OrganizationID": 1,
    "Loans": [{
        "Loan": "Test 001"
    }, {
        "Loan": "Test Loan 123"
    }, {
        "Loan": "Test Loan 234"
    }]
}

但是，我的要求是生成一个简单的 strings 数组，而不是一个 Loan 对象数组。

关于如何塑造 JSON 的建议将不胜感激！

Answer 1

JSON 字符串"用作分隔符，而不是'. 此外，我们应该注意逃逸（以防万一）。考虑到这些事情JSON_QUERY将帮助我们：

SELECT
    OrganizationID,
    JSON_QUERY((   
        SELECT '[' + STRING_AGG('"' + STRING_ESCAPE(Loan, 'json') + '"', ',') + ']' 
        FROM Loan 
        WHERE Loan.OrganizationID = Organization.OrganizationID
    )) AS [Loans]
FROM Organization 
WHERE OrganizationID = 1
FOR JSON PATH, WITHOUT_ARRAY_WRAPPER;