SequelizeでCASE WHEN式を使用するには？

Question

Node.jsにSequelize ORMを使用すると、select文でCASE/WHEN式をどのように使用しますか？

Sequelize Documentationに従ってSQL式CASEを使用するための参照や例はありません。これは可能ですか？

ここに私の例です：

SQL

SELECT userId, Status, 
    MAX(CASE Type WHEN 'Employee' THEN Rate ELSE 0 END) AS "Employee", 
    MAX(CASE Type WHEN 'School' THEN Rate ELSE 0 END) AS "School", 
    MAX(CASE Type WHEN 'Public' THEN Rate ELSE 0 END) AS "Public", 
    MAX(CASE Type WHEN 'Other' THEN Rate ELSE 0 END) AS "Other" 
FROM Database.dbo.invoice 
WHERE Status IN ('Included', 'Excluded') 
GROUP BY userId, Status 

Sequelize

var query = { 
    attributes: ['userId'], // need to include Rate (as Employee, School, Public, Other for each CASE/WHEN) 
    /* 
    MAX(CASE Type WHEN 'Employee' THEN Rate ELSE 0 END) AS "Employee", 
    MAX(CASE Type WHEN 'School' THEN Rate ELSE 0 END) AS "School", 
    MAX(CASE Type WHEN 'Public' THEN Rate ELSE 0 END) AS "Public", 
    MAX(CASE Type WHEN 'Other' THEN Rate ELSE 0 END) AS "Other" 
*/ 
    where: { 
    user: userId, 
    Type: ['Employee', 'School', 'Public', 'Other'], 
    }, 
    group: ['userId'], 
    raw: true 
}; 
models.invoice.findAll(query).then(result => { 
    console.log(result); 
}); 

データベース構造

+--------+------+----------+ 
| userId | Rate | Type  | 
+--------+------+----------+ 
| 1  | 2.00 | Employee | 
+--------+------+----------+ 
| 1  | 3.50 | School | 
+--------+------+----------+ 
| 1  | 4.00 | Public | 
+--------+------+----------+ 
| 1  | 2.50 | Other | 
+--------+------+----------+ 
| 2  | 3.75 | Employee | 
+--------+------+----------+ 
| 2  | 4.25 | School | 
+--------+------+----------+ 
| 2  | 2.00 | Public | 
+--------+------+----------+ 
| 2  | 3.00 | Other | 
+--------+------+----------+ 

望ましい結果：

+--------+----------+--------+--------+-------+ 
| userId | Employee | School | Public | Other | 
+--------+----------+--------+--------+-------+ 
| 1  | 2.00  | 3.50 | 4.00 | 2.50 | 
+--------+----------+--------+--------+-------+ 
| 2  | 3.75  | 4.25 | 2.00 | 3.00 | 
+--------+----------+--------+--------+-------+ 

Answer 1

あなたは特別なクエリ

var query = { 
    attributes: [ 
    'userId', 
    [Sequelize.literal(`MAX(CASE Type WHEN 'Employee' THEN Rate ELSE 0 END)`), 'Employee'], 
    [Sequelize.literal(`MAX(CASE Type WHEN 'School' THEN Rate ELSE 0 END)`), 'School'], 
    [Sequelize.literal(`MAX(CASE Type WHEN 'Public' THEN Rate ELSE 0 END)`), 'Public'], 
    [Sequelize.literal(`MAX(CASE Type WHEN 'Other' THEN Rate ELSE 0 END)`), 'Other'], 
    ], 
    where: { 
    user: userId, 
    Type: ['Employee', 'School', 'Public', 'Other'], 
    }, 
    group: ['userId'], 
    raw: true 
}; 
models.invoice.findAll(query).then(result => { 
    console.log(result); 
}); 

を構築するために attributesで Sequelize.literalを使用することができます