ArangoDB教程(二)-AQL语句使用,图使用，结合WEB界面端

迈不过友情╰ 2022-04-23 06:26 670阅读 0赞

**一.ArangoDB基本单元**  
1.Collections  
Collections相当于传统数据库的表，Collections有两种类型(不要和数据document混淆)  
(1)document collection图的节点  
(2)edge collection图的边  
和document类型相比，多出\_from和\_to属性，表示两个document之间的联系，换句话说就是:  
document collection的两个节点documents,通过edge collection边document来相连。  
**2.document文档**  
document 相当于传统数据库每一行数据，JSON格式，并自带3个属性，\_key，\_id，\_rev  
比如

{ 
        "_key": "2861650", //每个document的唯一标识，用于在collection集合中标识它，如果不设置的话会自动分配
        "_id": "Characters/2861650", //用于在database数据库中标识文档
        "_rev": "_V1bzsXa---", //对document的修订版本
        "name": "Ned",
        "surname": "Stark",
        "alive": true,
        "age": 41,
        "traits": ["A","H","C","N","P"]
    },

**二.AQL语句使用**  
**1.查询document**  
通过\_key获取

RETURN DOCUMENT("Characters", "2861650")

通过\_id获取

RETURN DOCUMENT("Characters/2861650")

获取所有表中所有数据

FOR c IN Characters
        RETURN c

条件查询

FOR c IN Characters
        FILTER c.name == "Ned"
        RETURN c
    FOR c IN Characters
        FILTER c.name == "Ned"
        RETURN c.age
    FOR c IN Characters
        FILTER c.age < 13 AND c.age != null
        RETURN { name: c.name, age: c.age }
    FOR c IN Characters
        FILTER c.age < 13 AND c.age != null
        RETURN { name: c.name, age: c.age }

限制查询的条数

FOR c IN Characters
        LIMIT 5
        RETURN c.name

排序  
此语句是先对name进行了排序，然后再进行Limit 10

FOR c IN Characters
        SORT c.name
        LIMIT 10	
        RETURN c.name

**2.插入ducument**  
单条document数据插入

INSERT {
        "name": "Robert",
        "surname": "Baratheon",
        "alive": false,
        "traits": ["A","H","C"]
    } INTO Characters

多条document数据插入

LET data = [
        { "name": "Robert", "surname": "Baratheon", "alive": false, "traits": ["A","H","C"] },
        { "name": "Jaime", "surname": "Lannister", "alive": true, "age": 36, "traits": ["A","F","B"] },
        { "name": "Catelyn", "surname": "Stark", "alive": false, "age": 40, "traits": ["D","H","C"] },
        { "name": "Cersei", "surname": "Lannister", "alive": true, "age": 36, "traits": ["H","E","F"] },
        { "name": "Daenerys", "surname": "Targaryen", "alive": true, "age": 16, "traits": ["D","H","C"] },
        { "name": "Jorah", "surname": "Mormont", "alive": false, "traits": ["A","B","C","F"] },
        { "name": "Petyr", "surname": "Baelish", "alive": false, "traits": ["E","G","F"] },
        { "name": "Viserys", "surname": "Targaryen", "alive": false, "traits": ["O","L","N"] },
        { "name": "Jon", "surname": "Snow", "alive": true, "age": 16, "traits": ["A","B","C","F"] },
        { "name": "Sansa", "surname": "Stark", "alive": true, "age": 13, "traits": ["D","I","J"] },
        { "name": "Arya", "surname": "Stark", "alive": true, "age": 11, "traits": ["C","K","L"] },
        { "name": "Robb", "surname": "Stark", "alive": false, "traits": ["A","B","C","K"] },
        { "name": "Theon", "surname": "Greyjoy", "alive": true, "age": 16, "traits": ["E","R","K"] },
        { "name": "Bran", "surname": "Stark", "alive": true, "age": 10, "traits": ["L","J"] },
        { "name": "Joffrey", "surname": "Baratheon", "alive": false, "age": 19, "traits": ["I","L","O"] },
        { "name": "Sandor", "surname": "Clegane", "alive": true, "traits": ["A","P","K","F"] },
        { "name": "Tyrion", "surname": "Lannister", "alive": true, "age": 32, "traits": ["F","K","M","N"] },
        { "name": "Khal", "surname": "Drogo", "alive": false, "traits": ["A","C","O","P"] },
        { "name": "Tywin", "surname": "Lannister", "alive": false, "traits": ["O","M","H","F"] },
        { "name": "Davos", "surname": "Seaworth", "alive": true, "age": 49, "traits": ["C","K","P","F"] },
        { "name": "Samwell", "surname": "Tarly", "alive": true, "age": 17, "traits": ["C","L","I"] },
        { "name": "Stannis", "surname": "Baratheon", "alive": false, "traits": ["H","O","P","M"] },
        { "name": "Melisandre", "alive": true, "traits": ["G","E","H"] },
        { "name": "Margaery", "surname": "Tyrell", "alive": false, "traits": ["M","D","B"] },
        { "name": "Jeor", "surname": "Mormont", "alive": false, "traits": ["C","H","M","P"] },
        { "name": "Bronn", "alive": true, "traits": ["K","E","C"] },
        { "name": "Varys", "alive": true, "traits": ["M","F","N","E"] },
        { "name": "Shae", "alive": false, "traits": ["M","D","G"] },
        { "name": "Talisa", "surname": "Maegyr", "alive": false, "traits": ["D","C","B"] },
        { "name": "Gendry", "alive": false, "traits": ["K","C","A"] },
        { "name": "Ygritte", "alive": false, "traits": ["A","P","K"] },
        { "name": "Tormund", "surname": "Giantsbane", "alive": true, "traits": ["C","P","A","I"] },
        { "name": "Gilly", "alive": true, "traits": ["L","J"] },
        { "name": "Brienne", "surname": "Tarth", "alive": true, "age": 32, "traits": ["P","C","A","K"] },
        { "name": "Ramsay", "surname": "Bolton", "alive": true, "traits": ["E","O","G","A"] },
        { "name": "Ellaria", "surname": "Sand", "alive": true, "traits": ["P","O","A","E"] },
        { "name": "Daario", "surname": "Naharis", "alive": true, "traits": ["K","P","A"] },
        { "name": "Missandei", "alive": true, "traits": ["D","L","C","M"] },
        { "name": "Tommen", "surname": "Baratheon", "alive": true, "traits": ["I","L","B"] },
        { "name": "Jaqen", "surname": "H'ghar", "alive": true, "traits": ["H","F","K"] },
        { "name": "Roose", "surname": "Bolton", "alive": true, "traits": ["H","E","F","A"] },
        { "name": "The High Sparrow", "alive": true, "traits": ["H","M","F","O"] }
    ]
    
    FOR d IN data
        INSERT d INTO Characters

**3.更新和替换document**  
更新，根据\_key

UPDATE "2861650" WITH { alive: false } IN Characters

替换

REPLACE "2861650" WITH {
        name: "Ned",
        surname: "Stark",
        alive: false,
        age: 41,
        traits: ["A","H","C","N","P"]
    } IN Characters

新增属性

FOR c IN Characters
        UPDATE c WITH { season: 1 } IN Characters

**4.删除document**  
单条删除

REMOVE "2861650" IN Characters

批量删除

FOR c IN Characters
        REMOVE c IN Characters

**5.MERGE()，collection之间的document关联**  
假如现在让Characters的traits字段和Traits中的数据相关联  
创建collection集合 Traits  
然后再导入数据

LET data =[
        { "_key": "A", "en": "strong", "de": "stark" },
        { "_key": "B", "en": "polite", "de": "freundlich" },
        { "_key": "C", "en": "loyal", "de": "loyal" },
        { "_key": "D", "en": "beautiful", "de": "schön" },
        { "_key": "E", "en": "sneaky", "de": "hinterlistig" },
        { "_key": "F", "en": "experienced", "de": "erfahren" },
        { "_key": "G", "en": "corrupt", "de": "korrupt" },
        { "_key": "H", "en": "powerful", "de": "einflussreich" },
        { "_key": "I", "en": "naive", "de": "naiv" },
        { "_key": "J", "en": "unmarried", "de": "unverheiratet" },
        { "_key": "K", "en": "skillful", "de": "geschickt" },
        { "_key": "L", "en": "young", "de": "jung" },
        { "_key": "M", "en": "smart", "de": "klug" },
        { "_key": "N", "en": "rational", "de": "rational" },
        { "_key": "O", "en": "ruthless", "de": "skrupellos" },
        { "_key": "P", "en": "brave", "de": "mutig" },
        { "_key": "Q", "en": "mighty", "de": "mächtig" },
        { "_key": "R", "en": "weak", "de": "schwach" }
    ]
    
    for d in data
        INSERT d INTO Traits

只关注traits字段和只拿en关联

FOR c IN Characters
        RETURN MERGE(c, { traits: DOCUMENT("Traits", c.traits)[*].en })

结果

{ 
        "_id": "Characters/7839",
        "_key": "7839",
        "_rev": "_YFmCBwS--_",
        "alive": false,
        "name": "Robert",
        "surname": "Baratheon",
        "traits": [
          "strong",
          "powerful",
          "loyal"
        ]
      }

traits字段和en，de关联

FOR c IN Characters
        RETURN MERGE(c, { traits: (for t in DOCUMENT("Traits", c.traits) RETURN {en:t.en,de:t.de})} )

结果

{ 
        "_id": "Characters/7839",
        "_key": "7839",
        "_rev": "_YFmCBwS--_",
        "alive": false,
        "name": "Robert",
        "surname": "Baratheon",
        "traits": [
          { 
            "en": "strong",
            "de": "stark"
          },
          { 
            "en": "powerful",
            "de": "einflussreich"
          },
          { 
            "en": "loyal",
            "de": "loyal"
          }
        ]
    }

**6.图的建立**  
比如父母和孩子之间有以下关系:  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEzMTEyOTE_size_16_color_FFFFFF_t_70]  
首先创建ChildOf的新集合，集合类型为Edge document  
Edge的\_from和\_to的内容必须为document的\_id,运行一下代码，生成图关系

LET data = [
        {
            "parent": { "name": "Ned", "surname": "Stark" },
            "child": { "name": "Robb", "surname": "Stark" }
        }, {
            "parent": { "name": "Ned", "surname": "Stark" },
            "child": { "name": "Sansa", "surname": "Stark" }
        }, {
            "parent": { "name": "Ned", "surname": "Stark" },
            "child": { "name": "Arya", "surname": "Stark" }
        }, {
            "parent": { "name": "Ned", "surname": "Stark" },
            "child": { "name": "Bran", "surname": "Stark" }
        }, {
            "parent": { "name": "Catelyn", "surname": "Stark" },
            "child": { "name": "Robb", "surname": "Stark" }
        }, {
            "parent": { "name": "Catelyn", "surname": "Stark" },
            "child": { "name": "Sansa", "surname": "Stark" }
        }, {
            "parent": { "name": "Catelyn", "surname": "Stark" },
            "child": { "name": "Arya", "surname": "Stark" }
        }, {
            "parent": { "name": "Catelyn", "surname": "Stark" },
            "child": { "name": "Bran", "surname": "Stark" }
        }, {
            "parent": { "name": "Ned", "surname": "Stark" },
            "child": { "name": "Jon", "surname": "Snow" }
        }, {
            "parent": { "name": "Tywin", "surname": "Lannister" },
            "child": { "name": "Jaime", "surname": "Lannister" }
        }, {
            "parent": { "name": "Tywin", "surname": "Lannister" },
            "child": { "name": "Cersei", "surname": "Lannister" }
        }, {
            "parent": { "name": "Tywin", "surname": "Lannister" },
            "child": { "name": "Tyrion", "surname": "Lannister" }
        }, {
            "parent": { "name": "Cersei", "surname": "Lannister" },
            "child": { "name": "Joffrey", "surname": "Baratheon" }
        }, {
            "parent": { "name": "Jaime", "surname": "Lannister" },
            "child": { "name": "Joffrey", "surname": "Baratheon" }
        }
    ]
    
    FOR rel in data
        LET parentId = FIRST(
            FOR c IN Characters
                FILTER c.name == rel.parent.name
                FILTER c.surname == rel.parent.surname
                LIMIT 1
                RETURN c._id
        )
        LET childId = FIRST(
            FOR c IN Characters
                FILTER c.name == rel.child.name
                FILTER c.surname == rel.child.surname
                LIMIT 1
                RETURN c._id
        )
        FILTER parentId != null AND childId != null
    	//顶点和边相连
        INSERT { _from: childId, _to: parentId } INTO ChildOf
        RETURN NEW

FIRST()从数据中取第一个元素  
NEW/OLD，NEW表示更改后的document,OLD表示更改之前的document

我们完成了关系的建立，尝试从关系中获取数据  
查看关系图

FOR c IN ChildOf
        RETURN c

但发现关系图的顶点都是用id表示，不易看清楚，可以使用以下语句查看

FOR c IN ChildOf
    	//CONCAT(c._from,DOCUMENT(c._from).name)
        RETURN {_key:c._key,_id:c._id,_from:DOCUMENT(c._from).name,_to:DOCUMENT(c._to).name,_rev:c._rev}

**对图的使用**  
从孩子找父母

FOR c IN Characters
        FILTER c.name == "Bran"
    	//1..1分别表示最小最大遍历深度，OUTBOUND表示沿着边的方向，INBOUND表示反方向
        FOR v IN 1..1 OUTBOUND c ChildOf
            RETURN v.name

从父母找孩子

FOR c IN Characters
        FILTER c.name == "Ned"
        FOR v IN 1..1 INBOUND c ChildOf
            RETURN v.name

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTEzMTEyOTE_size_16_color_FFFFFF_t_70]: /images/20220323/213aad27f24f4fe9a5d070c24f2787ce.png