现在我们可以尝试一些简单的搜索操作。运行搜索有两种基本方式：一种是通过 REST request URI 发送搜索参数，另外一种是通过 REST request body 发送搜索参数。第二种方法可以更富有表现力，你可以通过更自由的 JSON 格式去定义你的搜索。我们会用一个例子去展示如何使用第一种方法，对于教程的其余部分，我们会专门使用第二种方法。
搜索的 REST API 从_search端点开始，这个例子将返回bank索引中的所有文档：
curl 'localhost:9200/bank/_search?q=*&pretty'让我们分析一下这个搜索调用：我们搜索bank索引，通过q=*参数告诉 Elasticsearch 去匹配索引中的所有文档，pretty参数只是告诉 Elasticsearch 用漂亮的格式返回 JSON 结果。
响应（只显示部分结果）：
curl 'localhost:9200/bank/_search?q=*&pretty'
{
"took" : 63,
"timed_out" : false,
"_shards" : {
"total" : 5,
"successful" : 5,
"failed" : 0
},
"hits" : {
"total" : 1000,
"max_score" : 1.0,
"hits" : [ {
"_index" : "bank",
"_type" : "account",
"_id" : "1",
"_score" : 1.0, "_source" : {"account_number":1,"balance":39225,"firstname":"Amber","lastname":"Duke","age":32,"gender":"M","address":"880 Holmes Lane","employer":"Pyrami","email":"[email protected]","city":"Brogan","state":"IL"}
}, {
"_index" : "bank",
"_type" : "account",
"_id" : "6",
"_score" : 1.0, "_source" : {"account_number":6,"balance":5686,"firstname":"Hattie","lastname":"Bond","age":36,"gender":"M","address":"671 Bristol Street","employer":"Netagy","email":"[email protected]","city":"Dante","state":"TN"}
}, {
"_index" : "bank",
"_type" : "account",根据响应，我们可以看到以下几个部分：
took- Elasticsearch 执行搜索的时间（以毫秒为单位）timed_out－ 告诉我们搜索是否超时_shards－ 告诉我们多少分片被搜索，包括成功／失败的搜索分片的计数hits－ 搜索结果hits.total－ 匹配搜索标准的文档数量hits.hits－ 实际的搜索结果数组（默认前10个文档）_score和max_score－ 现在忽略这些字段
现在使用请求体方法实现和上面一样的搜索：
curl -XPOST 'localhost:9200/bank/_search?pretty' -d '
{
"query": { "match_all": {} }
}'不同之处在于，我们POST一个 JSON 样式的查询请求体到_search API，而不是在URL中添加q=*参数，我们将在下一节讨论 JSON 查询。
响应（部分显示）：
curl -XPOST 'localhost:9200/bank/_search?pretty' -d '
{
"query": { "match_all": {} }
}'
{
"took" : 26,
"timed_out" : false,
"_shards" : {
"total" : 5,
"successful" : 5,
"failed" : 0
},
"hits" : {
"total" : 1000,
"max_score" : 1.0,
"hits" : [ {
"_index" : "bank",
"_type" : "account",
"_id" : "1",
"_score" : 1.0, "_source" : {"account_number":1,"balance":39225,"firstname":"Amber","lastname":"Duke","age":32,"gender":"M","address":"880 Holmes Lane","employer":"Pyrami","email":"[email protected]","city":"Brogan","state":"IL"}
}, {
"_index" : "bank",
"_type" : "account",
"_id" : "6",
"_score" : 1.0, "_source" : {"account_number":6,"balance":5686,"firstname":"Hattie","lastname":"Bond","age":36,"gender":"M","address":"671 Bristol Street","employer":"Netagy","email":"[email protected]","city":"Dante","state":"TN"}
}, {
"_index" : "bank",
"_type" : "account",
"_id" : "13",一旦你获得了搜索结果，Elasticsearch 已经完全的完成了请求，它不会维护任何类型的服务端资源和打开游标到你的结果，理解这一点是非常重要的。这与 SQL 这样的平台形成了鲜明的对比，一开始你也许只想获取部分的查询结果，然后你想持续不断的获取结果，你可以通过有状态的服务端游标去获取剩下的数据。（注：其实我还不太明白这句话的意思）。