如何在ArangoDb中的下面的json文档中进行全文索引和搜索？

Question

{
"batters":
    {
    "batter":[
            { "id": "1001", "type": "Regular" },
            { "id": "1002", "type": "Chocolate" },
            { "id": "1003", "type": "Blueberry" },
            { "id": "1004", "type": "Devil's Food" }
    ]
    },
    "topping":[
            { "id": "5001", "type": "None" },
            { "id": "5002", "type": "Glazed" },
            { "id": "5005", "type": "Sugar" },
            { "id": "5007", "type": "Powdered Sugar" },
            { "id": "5006", "type": "Chocolate with Sprinkles" },
            { "id": "5003", "type": "Chocolate" },
            { "id": "5004", "type": "Maple" }
     ]
}

基本上要在这里进行全文搜索,我需要对"batters.batter"以及"batters.topping"进行索引,即两个属性.如何处理这种全文搜索.请解释一下该方法,我将通过REST API实现我的搜索.提前感谢你.

Answer 1

解决此问题的最佳方法是稍微更改数据布局,因为全文索引只能在一个属性上工作,而请求索引两次不会很快.因此,我们使用匿名图将字符串连接到它们的对象.

因此,我们创建两个(顶点)集合,一个边集合,一个带有fultext索引的顶点集合:

db._create("dishStrings")
db._createEdgeCollection("dishEdges")
db._create("dish")

db.dishStrings.ensureIndex({type: "fulltext", fields: [ "name" ]});

并将文件保存到他们关系中.我们使用_key用于引用_from和_to边缘关系中的顶点的属性:

db.dishStrings.save({"_key": "1001", "name": "Regular" , type: "Batter"});
db.dishStrings.save({"_key": "1002", "name": "Chocolate", type: "Batter" });
db.dishStrings.save({"_key": "1003", "name": "Blueberry", type: "Batter"});
db.dishStrings.save({"_key": "1004", "name": "Devil's Food", type: "Batter"});
db.dishStrings.save({"_key": "5001", "name": "None", type: "Topping"});
db.dishStrings.save({"_key": "5002", "name": "Glazed", type: "Topping"});
db.dishStrings.save({"_key": "5005", "name": "Sugar", type: "Topping"});
db.dishStrings.save({"_key": "5007", "name": "Powdered Sugar", type: "Topping"});
db.dishStrings.save({"_key": "5006", "name": "Chocolate with Sprinkles", type: "Topping"});
db.dishStrings.save({"_key": "5003", "name": "Chocolate", type: "Topping"});
db.dishStrings.save({"_key": "5004", "name": "Maple", type: "Topping"});

db.dishEdges.save("dishStrings/1001", "dish/batter", {tasty: true, type: "Batter"})
db.dishEdges.save("dishStrings/1002", "dish/batter", {tasty: true, type: "Batter"})
db.dishEdges.save("dishStrings/1003", "dish/batter", {tasty: true, type: "Batter"})
db.dishEdges.save("dishStrings/1004", "dish/batter", {tasty: true, type: "Batter"})
db.dishEdges.save("dishStrings/5001", "dish/batter", {tasty: true, type: "Topping"})
db.dishEdges.save("dishStrings/5002", "dish/batter", {tasty: true, type: "Topping"})
db.dishEdges.save("dishStrings/5003", "dish/batter", {tasty: true, type: "Topping"})
db.dishEdges.save("dishStrings/5004", "dish/batter", {tasty: true, type: "Topping"})
db.dishEdges.save("dishStrings/5005", "dish/batter", {tasty: true, type: "Topping"})
db.dishEdges.save("dishStrings/5006", "dish/batter", {tasty: true, type: "Topping"})
db.dishEdges.save("dishStrings/5007", "dish/batter", {tasty: true, type: "Topping"})

db.dish.save({_key: "batter", tasty: true})

我们重新验证全文索引将起作用:

db._query("FOR oneDishStr IN FULLTEXT(dishStrings, 'name', 'Chocolate')" +
          " RETURN oneDishStr").toArray()

(.toArray()将在控制台上打印出结果) 我们得到3次点击,一次击球,两次浇头.由于搜索字符串可能包含未经验证的字符串,因此我们宁愿使用绑定变量来规避注入:

db._query("FOR oneDishStr IN FULLTEXT(dishStrings, 'name', @searchString) " + 
          " RETURN oneDishStr", 
          {searchString: "Chocolate"});

现在让我们使用边缘关系来找到连接的菜:

db._query("FOR oneDishStr IN FULLTEXT(dishStrings, 'name', @searchString) "+ 
          "RETURN {str: oneDishStr, " + 
                  "dishes: NEIGHBORS(dishStrings, dishEdges, oneDishStr," + 
                                     " 'outbound')}",
           {searchString: "Chocolate"})

这是使用图表的旧(最多2.7)方式,因为我们想要使用快速过滤器,让我们将其转换为新的2.8语法:

db._query("FOR oneDishStr IN FULLTEXT(dishStrings, 'name', @searchString) " + 
          "  FOR v IN 1..1 OUTBOUND oneDishStr dishEdges RETURN " + 
          "    {str: oneDishStr, dish: v}",
         {searchString: "Chocolate"})

我们可以在两种情况下看到,我们为3个全文搜索命中中的每一个都获得了一次遍历Chocolate.现在我们只对这些命中感兴趣Toppings,所以我们将过滤所有非类型的边Topping:

db._query("FOR oneDishStr IN FULLTEXT(dishStrings, 'name', @searchString) "+
          "   FOR v, e IN 1..1 OUTBOUND oneDishStr dishEdges " + 
          "      FILTER e.type == 'Topping' " +
          "         RETURN {str: oneDishStr, dish: v}", 
          {searchString: "Chocolate"})