目录一、 将查询结果输出JSON格式1、FOR jsON AUTO:SELECT语句的结果以JSON输出。2、FOR JSON AUTO,Root(’&rsquo
SQL Server 2005开始支持XML数据类型,提供原生的XML数据类型、XML索引及各种管理或输出XML格式的函数。
随着JSON的流行,sql Server 2016开始支持JSON数据类型,不仅可以直接输出JSON格式的结果集,还能读取JSON格式的数据。
官方文档:https://docs.microsoft.com/zh-cn/sql/relational-databases/json/json-data-sql-server?view=sql-server-2017
下面是我们熟悉的SELECT及输出格式,后面对JSON的演示基于此SQL:
要将SELECT语句的结果以JSON输出,最简单的方法是在后面加上FOR JSON AUTO:
若要为FOR JSON加上Root Key,可以用ROOT选项来自定义ROOT 节点的名称:
若要自定义输出JSON格式的结构时,必须使用JSONPATH。
为NULL的数据在输出JSON时,会被忽略,若想要让NULL的字段也显示出来,可以加上选项INCLUDE_NULL_VALUES,该选项也适用于AUTO。
比如下面的SQL,增加了一个“SN”节点,把栏位SERNUM和CLIMAT放在里面:
演示实例:
select TOP (2) id, Plies, Createtime from [dbo].[B3PliesData] ORDER BY ID ;
--1178 3 2020-07-21 14:33:18.480
--1179 3 2020-07-21 14:36:27.457
select TOP (2) id, Plies as [myObject.Plies], Createtime as [myObject.Createtime] from [dbo].[B3PliesData] ORDER BY ID for json auto;
--[{"id":1178,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:33:18.480"},{"id":1179,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:36:27.457"}]
select TOP (2) id, Plies, Createtime from [dbo].[B3PliesData] ORDER BY ID for json auto ,root('myRoot') ;
--{"myRoot":[{"id":1178,"Plies":3,"Createtime":"2020-07-21T14:33:18.480"},{"id":1179,"Plies":3,"Createtime":"2020-07-21T14:36:27.457"}]}
select TOP (2) id, Plies as [myObject.Plies], Createtime as [myObject.Createtime] from [dbo].[B3PliesData] ORDER BY ID for json path;
--[{"id":1178,"myObject":{"Plies":3,"Createtime":"2020-07-21T14:33:18.480"}},{"id":1179,"myObject":{"Plies":3,"Createtime":"2020-07-21T14:36:27.457"}}]
select TOP (2) id, Plies, Createtime,null as mynull from [dbo].[B3PliesData] ORDER BY ID for json path,root('myRoot');
--{"myRoot":[{"id":1178,"Plies":3,"Createtime":"2020-07-21T14:33:18.480"},{"id":1179,"Plies":3,"Createtime":"2020-07-21T14:36:27.457"}]}
select TOP (2) id, Plies, Createtime,null as mynull from [dbo].[B3PliesData] ORDER BY ID for json path,root('myRoot'),include_null_values;
--{"myRoot":[{"id":1178,"Plies":3,"Createtime":"2020-07-21T14:33:18.480","mynull":null},{"id":1179,"Plies":3,"Createtime":"2020-07-21T14:36:27.457","mynull":null}]}
实例演示:
-------------1、-------------
declare @json as varchar(8000)
set @json='[
{"id":1178,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:33:18.480"},
{"id":1179,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:36:27.457"}]'
select * from openjson(@json);
--key value type
--0 {"id":1178,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:33:18.480"} 5
--1 {"id":1179,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:36:27.457"} 5
-------------2、-------------
declare @json1 as varchar(8000)
set @json1='[
{"id":1178,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:33:18.480"},
{"id":1179,"myObject.Plies":3,"myObject.Createtime":"2020-07-21T14:36:27.457"}]
'
select * from openjson(@json1)
with(
id varchar(10) '$.id',
Plies int '$."myObject.Plies"',
Createtime datetime '$."myObject.Createtime"'
);
--id Plies Createtime
--1178 3 2020-07-21 14:33:18.480
--1179 3 2020-07-21 14:36:27.457
-------------3、-------------
declare @json2 as varchar(8000)
set @json2='{"myRoot":[
{"id":1178,"myObject":{"Plies":3,"Createtime":"2020-07-21T14:33:18.480"}},
{"id":1179,"myObject":{"Plies":3,"Createtime":"2020-07-21T14:36:27.457"}}
]}'
select * from openjson(@json2,'$.myRoot')
with(
id varchar(10) ,
Plies int '$.myObject.Plies',
Createtime datetime '$.myObject.Createtime'
);
--id Plies Createtime
--1178 3 2020-07-21 14:33:18.480
--1179 3 2020-07-21 14:36:27.457
declare @param nvarchar(max);
set @param = N'{
"info":{
"type":1,
"address":{
"town":"Bristol",
"county":"Avon",
"country":"England"
},
"tags":["Sport", "Water polo"]
},
"type":"Basic"
}';
print iif(isjson(@param) > 0, 'OK', 'NO');
返回:OK
print json_value(@param, '$.info.address.town');
print json_value(@param, '$.info.tags[1]');
返回:Bristol,Water polo
print json_query(@param, '$.info');
{
"type":1,
"address":{
"town":"Bristol",
"county":"Avon",
"country":"England"
},
"tags":["Sport", "Water polo"]
}
print json_modify(@param, '$.info.address.town', 'London');
返回:
{
"info":{
"type":1,
"address":{
"town":"London",
"county":"Avon",
"country":"England"
},
"tags":["Sport", "Water polo"]
},
"type":"Basic"
}
实例演示:
declare @param nvarchar(max);
set @param=N'{
"info":{
"type":1,
"address":{
"town":"Bristol",
"county":"Avon",
"country":"England"
},
"tags":["Sport", "Water polo"]
},
"type":"Basic"
}';
print iif(isjson(@param)>0, 'OK', 'NO');
print json_query(@param);
print json_value(@param, '$.info.address.town');
print json_value(@param, '$.info.tags[1]');
print json_query(@param, '$.info');
print json_query('["2020-1-8","2020-1-9"]');
print json_modify(@param, '$.info.address.town', 'London');
SQL2016 中的新增的内置JSON进行了简单介绍,主要有如下要点:
到此这篇关于SQL Server使用JSON函数的文章就介绍到这了。希望对大家的学习有所帮助,也希望大家多多支持编程网。
--结束END--
本文标题: SQL Server中JSON函数的用法详解
本文链接: https://www.lsjlt.com/news/149386.html(转载时请注明来源链接)
有问题或投稿请发送至: 邮箱/279061341@qq.com QQ/279061341
下载Word文档到电脑,方便收藏和打印~
2024-03-01
2024-03-01
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
2024-02-29
回答
回答
回答
回答
回答
回答
回答
回答
回答
回答
0