JavaScript数据库TaffyDB用法实例分析_javascript技巧

本文实例讲述了JavaScript数据库TaffyDB用法。分享给大家供大家参考。具体如下：

TaffyDB 是一个免费开源的 JavaScript 库，用于在 Web 上实现一个轻量级的数据访问层，也就是一个简单的数据库。

数据定义：

var friends = new TAFFY(
[
{name:"Bob",
 gender:"M",
 married:"No",
 age:25,
 state:"NY",
 favorite_foods:["pizza","tacos"]},
 {name:"Joyce",
 gender:"F",
 married:"No",
 age:29,
 state:"WA",
 favorite_foods:["salad","cheese sticks"]},
 {name:"Dan",
 gender:"M",
 married:"No",
 age:29,
 state:"MT",
 favorite_foods:["pizza","hamburgers","BLTs"]},
 {name:"Sarah",
 gender:"F",
 married:"No",
 age:21,
 state:"ID",
 favorite_foods:["pizza","sushi"]}
 ]
)

查询：

friends.find({age:{greaterthan:22}});
friends.find({state:["WA","MT","ID"]});
friends.find({state:["WA","MT","ID"],
       age:{greaterthan:22}});

更新操作：

friends.update(
  {
  state:"CA",
  married:"Yes"
  },
  {
  name:"Joyce"
  }
  );
friends.update({state:"CA",married:"Yes"},1);
friends.update(
  {
  state:"CA",
  married:"Yes"
  },
  friends.find(
    {name:"Joyce"}
    )
  );

插入数据：

//Inserting is simple and works as you would expect:
friends.insert(
  {name:"Brian",
  gender:"M",
  married:"No",
  age:52,
  state:"FL",
  favorite_foods:["fruit","steak"]
  });

删除：

复制代码 代码如下:

friends.remove({name:"Brian"});

排序：

friends.orderBy(["age",{"name":"desc"}]);
var keys = new TAFFY([
{name:"12abc"},
{name:"abc343"},
{name:"1abc"},
{name:"23abc"}
]);
keys.orderBy({name:"logical"});

forEach用法：

friends.forEach(function (f,n) {alert(f.name)});
friends.forEach(
  function (f,n) {alert(f.name);},
  {favorite_foods:{has:"pizza"}}
);

希望本文所述对大家的javascript程序设计有所帮助。