Filter 在Dataweave 2.0中使用两个或更多列值比较两个JSON数组

我有一项任务，需要使用每个数组的一列，根据相同的值比较和过滤两个

JSON

数组。所以我用了这个问题的答案

但是，现在我需要比较两个

JSON

数组，它们匹配两个甚至三个列的值

我已经试着在另一个中使用一个

map

，但是，它不起作用

这些例子可能就是我所用答案中的例子。比较

db.code=file.code

，

db.name=file.nm

和

db.id=file.identity

var db = [
    {
        "CODE": "A11",
        "NAME": "Alpha",
        "ID": "C10000"
    },
    {
        "CODE": "B12",
        "NAME": "Bravo",
        "ID": "B20000"
    },
    {
        "CODE": "C11",
        "NAME": "Charlie",
        "ID": "C30000"
    },
    {
        "CODE": "D12",
        "NAME": "Delta",
        "ID": "D40000"
    },
    {
        "CODE": "E12",
        "NAME": "Echo",
        "ID": "E50000"
    }
]  



var file = [
    {
        "IDENTITY": "D40000",
        "NM": "Delta",
        "CODE": "D12"
    },
    {
        "IDENTITY": "C30000",
        "NM": "Charlie",
        "CODE": "C11"
    }
]

---

看看这对你有用吗

%dw 2.0
output application/json
var file = [
    {
        "IDENTITY": "D40000",
        "NM": "Delta",
        "CODE": "D12"
    },
    {
        "IDENTITY": "C30000",
        "NM": "Charlie",
        "CODE": "C11"
    }
]
var db = [
    {
        "CODE": "A11",
        "NAME": "Alpha",
        "ID": "C10000"
    },
    {
        "CODE": "B12",
        "NAME": "Bravo",
        "ID": "B20000"
    },
    {
        "CODE": "C11",
        "NAME": "Charlie",
        "ID": "C30000"
    },
    {
        "CODE": "D12",
        "NAME": "Delta",
        "ID": "D40000"
    },
    {
        "CODE": "E12",
        "NAME": "Echo",
        "ID": "E50000"
    }
]
---
file flatMap(v) -> ( 
    db filter (v.IDENTITY == $.ID and v.NM == $.NAME and v.CODE == $.CODE)
)

---

使用

flatMap

而不是

map

进行展平，否则将在输出中获得更干净的数组数组，除非您希望每个

文件

条目可能有多个匹配项，在这种情况下，我将坚持使用

map
查看这是否适合您

%dw 2.0
output application/json
var file = [
    {
        "IDENTITY": "D40000",
        "NM": "Delta",
        "CODE": "D12"
    },
    {
        "IDENTITY": "C30000",
        "NM": "Charlie",
        "CODE": "C11"
    }
]
var db = [
    {
        "CODE": "A11",
        "NAME": "Alpha",
        "ID": "C10000"
    },
    {
        "CODE": "B12",
        "NAME": "Bravo",
        "ID": "B20000"
    },
    {
        "CODE": "C11",
        "NAME": "Charlie",
        "ID": "C30000"
    },
    {
        "CODE": "D12",
        "NAME": "Delta",
        "ID": "D40000"
    },
    {
        "CODE": "E12",
        "NAME": "Echo",
        "ID": "E50000"
    }
]
---
file flatMap(v) -> ( 
    db filter (v.IDENTITY == $.ID and v.NM == $.NAME and v.CODE == $.CODE)
)

使用
flatMap
而不是
map
进行展平，否则将在输出中获得更干净的数组数组，除非您希望每个
文件
条目可能有多个匹配项，在这种情况下，我坚持使用
map
可以直接比较DW中的对象，因此，可以将链接的解决方案修改为以下内容：

%dw 2.0
import * from dw::core::Arrays
output application/json
var db = [
    {
        "CODE": "A11",
        "NAME": "Alpha",
        "ID": "C10000"
    },
    {
        "CODE": "B12",
        "NAME": "Bravo",
        "ID": "B20000"
    },
    {
        "CODE": "C11",
        "NAME": "Charlie",
        "ID": "C30000"
    },
    {
        "CODE": "D12",
        "NAME": "Delta",
        "ID": "D40000"
    },
    {
        "CODE": "E12",
        "NAME": "Echo",
        "ID": "E50000"
    }
]  

var file = [
    {
        "IDENTITY": "D40000",
        "NM": "Delta",
        "CODE": "D12"
    },
    {
        "IDENTITY": "C30000",
        "NM": "Charlie",
        "CODE": "C11"
    }
]
---
db partition (e) -> file contains {IDENTITY:e.ID,NM:e.NAME,CODE:e.CODE}

可以直接比较DW中的对象，因此可以将链接的解决方案修改为以下内容：

%dw 2.0
import * from dw::core::Arrays
output application/json
var db = [
    {
        "CODE": "A11",
        "NAME": "Alpha",
        "ID": "C10000"
    },
    {
        "CODE": "B12",
        "NAME": "Bravo",
        "ID": "B20000"
    },
    {
        "CODE": "C11",
        "NAME": "Charlie",
        "ID": "C30000"
    },
    {
        "CODE": "D12",
        "NAME": "Delta",
        "ID": "D40000"
    },
    {
        "CODE": "E12",
        "NAME": "Echo",
        "ID": "E50000"
    }
]  

var file = [
    {
        "IDENTITY": "D40000",
        "NM": "Delta",
        "CODE": "D12"
    },
    {
        "IDENTITY": "C30000",
        "NM": "Charlie",
        "CODE": "C11"
    }
]
---
db partition (e) -> file contains {IDENTITY:e.ID,NM:e.NAME,CODE:e.CODE}

您可以直接使用
过滤器
，也可以使用
包含

db filter(value) -> file contains {IDENTITY: value.ID, NM: value.NAME, CODE: value.CODE}

这告诉您根据文件是否包含对象
{IDENTITY:value.ID，NM:value.NAME，code:value.code}
来过滤db数组。但是，如果文件数组中的对象具有其他不用于比较的字段，则此操作将不起作用。使用上述方法，您可以更新筛选条件，以检查文件数组中是否存在条件适用的对象（使用数据选择器）。您可以使用下面的选项来检查

db filter(value) -> file[?($.IDENTITY==value.ID and $.NM == value.NAME and $.CODE == value.CODE)] != null

您可以直接使用
过滤器
，也可以使用
包含

db filter(value) -> file contains {IDENTITY: value.ID, NM: value.NAME, CODE: value.CODE}

这告诉您根据文件是否包含对象
{IDENTITY:value.ID，NM:value.NAME，code:value.code}
来过滤db数组。但是，如果文件数组中的对象具有其他不用于比较的字段，则此操作将不起作用。使用上述方法，您可以更新筛选条件，以检查文件数组中是否存在条件适用的对象（使用数据选择器）。您可以使用下面的选项来检查

db filter(value) -> file[?($.IDENTITY==value.ID and $.NM == value.NAME and $.CODE == value.CODE)] != null