如何在Mongo DB中合并数组和文档字段

时间:2020-01-06 07:38:12

标签: mongodb mongodb-query aggregation-framework

我在MongoDB中有此文档

[
    {
        "locations": [5, 5],
        "id": "fff"
    },
    {
        "locations": [7, 7],
        "id": "aaa"
    },
    {
        "locations": [9, 9],
        "id": "ccc"
    }
]

我想将数组字段和字符串字段合并到包含这样的组合的字段中

{
    "device": [
        ["fff", 5, 5],
        ["aaa", 7, 7],
        ["ccc", 9, 9]
    ]
}

是否可以通过聚合来做到这一点?谢谢。

1 个答案:

答案 0 :(得分:1)

您可以使用$concatArrays合并两个字段,然后使用$group使其成为二维数组

buildscript {
    repositories {
        maven { url = 'https://files.minecraftforge.net/maven' }
        jcenter()
        mavenCentral()
    }
    dependencies {
        classpath group: 'net.minecraftforge.gradle', name: 'ForgeGradle', version: '3.+', changing: true
    }
}
apply plugin: 'net.minecraftforge.gradle'
// Only edit below this line, the above code adds and enables the necessary things for Forge to be setup.
apply plugin: 'eclipse'
apply plugin: 'maven-publish'

version = '1.0'
group = 'com.yourname.modid' // http://maven.apache.org/guides/mini/guide-naming-conventions.html
archivesBaseName = 'modid'

sourceCompatibility = targetCompatibility = compileJava.sourceCompatibility = compileJava.targetCompatibility = '1.8' // Need this here so eclipse task generates correctly.

minecraft {
    // The mappings can be changed at any time, and must be in the following format.
    // snapshot_YYYYMMDD   Snapshot are built nightly.
    // stable_#            Stables are built at the discretion of the MCP team.
    // Use non-default mappings at your own risk. they may not always work.
    // Simply re-run your setup task after changing the mappings to update your workspace.
    mappings channel: 'snapshot', version: '20190719-1.14.3'
    // makeObfSourceJar = false // an Srg named sources jar is made by default. uncomment this to disable.

    // accessTransformer = file('src/main/resources/META-INF/accesstransformer.cfg')

    // Default run configurations.
    // These can be tweaked, removed, or duplicated as needed.
    runs {
        client {
            workingDirectory project.file('run')

            // Recommended logging data for a userdev environment
            property 'forge.logging.markers', 'SCAN,REGISTRIES,REGISTRYDUMP'

            // Recommended logging level for the console
            property 'forge.logging.console.level', 'debug'

            mods {
                examplemod {
                    source sourceSets.main
                }
            }
        }

        server {
            workingDirectory project.file('run')

            // Recommended logging data for a userdev environment
            property 'forge.logging.markers', 'SCAN,REGISTRIES,REGISTRYDUMP'

            // Recommended logging level for the console
            property 'forge.logging.console.level', 'debug'

            mods {
                examplemod {
                    source sourceSets.main
                }
            }
        }

        data {
            workingDirectory project.file('run')

            // Recommended logging data for a userdev environment
            property 'forge.logging.markers', 'SCAN,REGISTRIES,REGISTRYDUMP'

            // Recommended logging level for the console
            property 'forge.logging.console.level', 'debug'

            args '--mod', 'examplemod', '--all', '--output', file('src/generated/resources/')

            mods {
                examplemod {
                    source sourceSets.main
                }
            }
        }
    }
}

dependencies {
    // Specify the version of Minecraft to use, If this is any group other then 'net.minecraft' it is assumed
    // that the dep is a ForgeGradle 'patcher' dependency. And it's patches will be applied.
    // The userdev artifact is a special name and will get all sorts of transformations applied to it.
    minecraft 'net.minecraftforge:forge:1.15.1-30.0.26'

    // You may put jars on which you depend on in ./libs or you may define them like so..
    // compile "some.group:artifact:version:classifier"
    // compile "some.group:artifact:version"

    // Real examples
    // compile 'com.mod-buildcraft:buildcraft:6.0.8:dev'  // adds buildcraft to the dev env
    // compile 'com.googlecode.efficient-java-matrix-library:ejml:0.24' // adds ejml to the dev env

    // The 'provided' configuration is for optional dependencies that exist at compile-time but might not at runtime.
    // provided 'com.mod-buildcraft:buildcraft:6.0.8:dev'

    // These dependencies get remapped to your current MCP mappings
    // deobf 'com.mod-buildcraft:buildcraft:6.0.8:dev'

    // For more info...
    // http://www.gradle.org/docs/current/userguide/artifact_dependencies_tutorial.html
    // http://www.gradle.org/docs/current/userguide/dependency_management.html

}

// Example for how to get properties into the manifest for reading by the runtime..
jar {
    manifest {
        attributes([
            "Specification-Title": "examplemod",
            "Specification-Vendor": "examplemodsareus",
            "Specification-Version": "1", // We are version 1 of ourselves
            "Implementation-Title": project.name,
            "Implementation-Version": "${version}",
            "Implementation-Vendor" :"examplemodsareus",
            "Implementation-Timestamp": new Date().format("yyyy-MM-dd'T'HH:mm:ssZ")
        ])
    }
}

// Example configuration to allow publishing using the maven-publish task
// we define a custom artifact that is sourced from the reobfJar output task
// and then declare that to be published
// Note you'll need to add a repository here
def reobfFile = file("$buildDir/reobfJar/output.jar")
def reobfArtifact = artifacts.add('default', reobfFile) {
    type 'jar'
    builtBy 'reobfJar'
}
publishing {
    publications {
        mavenJava(MavenPublication) {
            artifact reobfArtifact
        }
    }
    repositories {
        maven {
            url "file:///${project.projectDir}/mcmodsrepo"
        }
    }
}

Output

db.collection.aggregate([
  { "$group": {
    "_id": null,
    "devices": { "$push": { "$concatArrays": [["$id"], "$locations"] } }
  }}
])