JavaScript数据库TaffyDB用法实例分析

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：

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。