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：
varfriends=newTAFFY(
[
{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","cheesesticks"]},
{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：
//Insertingissimpleandworksasyouwouldexpect:
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"}]);
varkeys=newTAFFY([
{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。