Redis JSON介绍和命令大全

Redis JSON介绍和命令大全

  • Redis JSON
    • 先说说`JSON`是什么
    • 再说说`JSON Path`
      • 先推荐两个网站
      • `JSONPath JAVA clents`
    • `Redis JSON` 安装
    • 内存
    • json命令语法
      • 命令url
      • 命令解释
          • `JSON.ARRAPPEND`
          • `JSON.ARRINDEX`
          • `JSON.ARRINSERT`
          • `JSON.ARRLEN`
          • `JSON.ARRPOP`
          • `JSON.ARRTRIM`
          • `JSON.CLEAR`
          • `JSON.DEBUG MEMORY`
          • `JSON.DEBUG`
          • `JSON.DEL`
          • `JSON.FORGET`
          • `JSON.GET`
          • `JSON.MERGE`
          • `JSON.MGET`
          • `JSON.MSET`
          • `JSON.NUMINCRBY`
          • `JSON.OBJKEYS`
          • `JSON.OBJLEN`
          • `JSON.SET`
          • `JSON.STRAPPEND`
          • `JSON.STRLEN`
          • `JSON.TOGGLE`
          • `JSON.TYPE`
      • 增
      • 删
      • 改
      • 查
    • `redis json`的`clients`
    • `redis json`的使用场景 https://redis.io/docs/latest/develop/data-types/json/use_cases/

Redis JSON

redis在6.x开始支持json
注意：json可以说是在http接口返回值的网红，之所以说是网红，是因为之前不是json，之后当然也就未可知也。
注意我上面只说了在http接口返回值的场景。实际上在内部的rpc调用，也有用json传输的，不过这比较小众。
更多使用在存储数据场景下，也是泛滥的场景，如mysql、es、mongodb、redis中，json似乎包罗万象了。
⚠️注意！这不是好事，灵活性的提升必定伴随着其他如规范性、稳定性等问题的到来，
如果还没有到来，那肯定是时间还不够长、业务还没有增长。

redis官网介绍 https://redis.io/docs/latest/develop/data-types/json/

先说说JSON是什么

JSON 指的是 JavaScript 对象表示法（JavaScript Object Notation）

再说说JSON Path

JSONPath是一种用于从JSON文档中提取信息的查询语言，类似于XML的XPath。

先推荐两个网站

JsonPath语法 https://goessner.net/articles/JsonPath/
JsonPath在线 https://jsonpath.com/
在这里插入图片描述
在这里插入图片描述

在这里插入图片描述

JSONPath JAVA clents

<dependency><groupId>com.jayway.jsonpath</groupId><artifactId>json-path</artifactId><version>2.7.0</version> <!-- 请检查是否有更新的版本 -->
</dependency>

Redis JSON 安装

  1. 使用redis-stack
    docker run -it --name redis-stack -p 6379:6379 redis/redis-stack:latest
  2. 使用redis 6.x及以上，配置loadMoudle
    本文使用redis-stack，如下图，可以看到启动的时候自动加载了json模块，
    除此之外还有timeseries、search等模块

在这里插入图片描述

内存

官网内存 https://redis.io/docs/latest/develop/data-types/json/ram/
在这里插入图片描述
可以看到json的内存还是挺恐怖的，哈哈哈，用不上还是用string吧…
key和value都占用内存

json命令语法

json命令大全 https://redis.io/docs/latest/commands/?group=json
在这里插入图片描述

命令url

indexcommandurl
0JSON.ARRAPPENDhttps://redis.io/docs/latest/commands/json.arrappend/
1JSON.ARRINDEXhttps://redis.io/docs/latest/commands/json.arrindex/
2JSON.ARRINSERThttps://redis.io/docs/latest/commands/json.arrinsert/
3JSON.ARRLENhttps://redis.io/docs/latest/commands/json.arrlen/
4JSON.ARRPOPhttps://redis.io/docs/latest/commands/json.arrpop/
5JSON.ARRTRIMhttps://redis.io/docs/latest/commands/json.arrtrim/
6JSON.CLEARhttps://redis.io/docs/latest/commands/json.clear/
7JSON.DEBUGhttps://redis.io/docs/latest/commands/json.debug/
8JSON.DEBUG MEMORYhttps://redis.io/docs/latest/commands/json.debug-memory/
9JSON.DELhttps://redis.io/docs/latest/commands/json.del/
10JSON.FORGEThttps://redis.io/docs/latest/commands/json.forget/
11JSON.GEThttps://redis.io/docs/latest/commands/json.get/
12JSON.MERGEhttps://redis.io/docs/latest/commands/json.merge/
13JSON.MGEThttps://redis.io/docs/latest/commands/json.mget/
14JSON.MSEThttps://redis.io/docs/latest/commands/json.mset/
15JSON.NUMINCRBYhttps://redis.io/docs/latest/commands/json.numincrby/
16JSON.NUMMULTBYhttps://redis.io/docs/latest/commands/json.nummultby/
17JSON.OBJKEYShttps://redis.io/docs/latest/commands/json.objkeys/
18JSON.OBJLENhttps://redis.io/docs/latest/commands/json.objlen/
19JSON.RESPhttps://redis.io/docs/latest/commands/json.resp/
20JSON.SEThttps://redis.io/docs/latest/commands/json.set/
21JSON.STRAPPENDhttps://redis.io/docs/latest/commands/json.strappend/
22JSON.STRLENhttps://redis.io/docs/latest/commands/json.strlen/
23JSON.TOGGLEhttps://redis.io/docs/latest/commands/json.toggle/
24JSON.TYPEhttps://redis.io/docs/latest/commands/json.type/

命令解释

JSON.ARRAPPEND
commandJSON.ARRAPPEND
syntaxJSON.ARRAPPEND key [path] value [value ...]
description

Append the json values into the array at path after the last element in it

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.arrappend/
JSON.ARRINDEX
commandJSON.ARRINDEX
syntaxJSON.ARRINDEX key path value [start [stop]]
description

Search for the first occurrence of a JSON value in an array

time complexityO(N) when path is evaluated to a single value where N is the size of the array, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.arrindex/
JSON.ARRINSERT
commandJSON.ARRINSERT
syntaxJSON.ARRINSERT key path index value [value ...]
description

Insert the json values into the array at path before the index (shifts to the right)

time complexityO(N) when path is evaluated to a single value where N is the size of the array, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.arrinsert/
JSON.ARRLEN
commandJSON.ARRLEN
syntaxJSON.ARRLEN key [path]
description

Report the length of the JSON array at path in key

time complexityO(1) where path is evaluated to a single value, O(N) where path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.arrlen/
JSON.ARRPOP
commandJSON.ARRPOP
syntaxJSON.ARRPOP key [path [index]]
description

Remove and return an element from the index in the array

time complexityO(N) when path is evaluated to a single value where N is the size of the array and the specified index is not the last element, O(1) when path is evaluated to a single value and the specified index is the last element, or O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.arrpop/
JSON.ARRTRIM
commandJSON.ARRTRIM
syntaxJSON.ARRTRIM key path start stop
description

Trim an array so that it contains only the specified inclusive range of elements

time complexityO(N) when path is evaluated to a single value where N is the size of the array, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.arrtrim/
JSON.CLEAR
commandJSON.CLEAR
syntaxJSON.CLEAR key [path]
description

Clear container values (arrays/objects) and set numeric values to 0

time complexityO(N) when path is evaluated to a single value where N is the size of the values, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 2.0.0
urlhttps://redis.io/docs/latest/commands/json.clear/
JSON.DEBUG MEMORY
commandJSON.DEBUG MEMORY
syntaxJSON.DEBUG MEMORY key [path]
description

Report a value’s memory usage in bytes

time complexityO(N) when path is evaluated to a single value, where N is the size of the value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.debug-memory/
JSON.DEBUG
commandJSON.DEBUG
syntaxJSON.DEBUG
description

This is a container command for debugging related tasks.

time complexityN/A
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.debug/
JSON.DEL
commandJSON.DEL
syntaxJSON.DEL key [path]
description

Delete a value

time complexityO(N) when path is evaluated to a single value where N is the size of the deleted value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.del/
JSON.FORGET
commandJSON.FORGET
syntaxJSON.FORGET key [path]
description

See JSON.DEL.

time complexityO(N) when path is evaluated to a single value where N is the size of the deleted value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.forget/
JSON.GET
commandJSON.GET
syntaxJSON.GET key [INDENTÂ indent] [NEWLINEÂ newline] [SPACEÂ space] [path [path ...]]
description

Return the value at path in JSON serialized form

time complexityO(N) when path is evaluated to a single value where N is the size of the value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.get/
JSON.MERGE
commandJSON.MERGE
syntaxJSON.MERGE key path value
description

Merge a given JSON value into matching paths. Consequently, JSON values at matching paths are updated, deleted, or expanded with new children.

time complexityO(M+N) when path is evaluated to a single value where M is the size of the original value (if it exists) and N is the size of the new value, O(M+N) when path is evaluated to multiple values where M is the size of the key and N is the size of the new value * the number of original values in the key
available inRedis Stack / JSON 2.6.0
urlhttps://redis.io/docs/latest/commands/json.merge/
JSON.MGET
commandJSON.MGET
syntaxJSON.MGET key [key ...] path
description

Return the values at path from multiple key arguments

time complexityO(M*N) when path is evaluated to a single value where M is the number of keys and N is the size of the value, O(N1+N2+…+Nm) when path is evaluated to multiple values where m is the number of keys and Ni is the size of the i-th key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.mget/
JSON.MSET
commandJSON.MSET
syntaxJSON.MSET key path value [key path value ...]
description

Set or update one or more JSON values according to the specified key-path-value triplets

time complexityO(K*(M+N)) where k is the number of keys in the command, when path is evaluated to a single value where M is the size of the original value (if it exists) and N is the size of the new value, or O(K*(M+N)) when path is evaluated to multiple values where M is the size of the key and N is the size of the new value * the number of original values in the key
available inRedis Stack / JSON 2.6.0
urlhttps://redis.io/docs/latest/commands/json.mset/
JSON.NUMINCRBY
commandJSON.NUMINCRBY
syntaxJSON.NUMINCRBY key path value
description

Increment the number value stored at path by number

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.numincrby/
JSON.OBJKEYS
commandJSON.OBJKEYS
syntaxJSON.OBJKEYS key [path]
description

Return the keys in the object that’s referenced by path

time complexityO(N) when path is evaluated to a single value, where N is the number of keys in the object, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.objkeys/
JSON.OBJLEN
commandJSON.OBJLEN
syntaxJSON.OBJLEN key [path]
description

Report the number of keys in the JSON object at path in key

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.objlen/
JSON.SET
commandJSON.SET
syntaxJSON.SET key path value [NX | XX]
description

Set the JSON value at path in key

time complexityO(M+N) when path is evaluated to a single value where M is the size of the original value (if it exists) and N is the size of the new value, O(M+N) when path is evaluated to multiple values where M is the size of the key and N is the size of the new value * the number of original values in the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.set/
JSON.STRAPPEND
commandJSON.STRAPPEND
syntaxJSON.STRAPPEND key [path] value
description

Append the json-string values to the string at path

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.strappend/
JSON.STRLEN
commandJSON.STRLEN
syntaxJSON.STRLEN key [path]
description

Report the length of the JSON String at path in key

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.strlen/
JSON.TOGGLE
commandJSON.TOGGLE
syntaxJSON.TOGGLE key path
description

Toggle a Boolean value stored at path

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 2.0.0
urlhttps://redis.io/docs/latest/commands/json.toggle/
JSON.TYPE
commandJSON.TYPE
syntaxJSON.TYPE key [path]
description

Report the type of JSON value at path

time complexityO(1) when path is evaluated to a single value, O(N) when path is evaluated to multiple values, where N is the size of the key
available inRedis Stack / JSON 1.0.0
urlhttps://redis.io/docs/latest/commands/json.type/

增

  • JSON.ARRAPPEND
127.0.0.1:6379> json.set blog $ '{"user":{"id":222078,"nick":"TOM"},"id":1000,"content":"一起学习redis json吧","delete":false,"like":300,"tags":["redis","json"]}'
127.0.0.1:6379> json.arrappend blog $.tags '"backend"' '"midware"'
4
127.0.0.1:6379> json.get blog INDENT "\t" NEWLINE "\n" SPACE " " $
[{"user": {"id": 222078,"nick": "TOM"},"id": 1000,"content": "一起学习redis json吧","delete": false,"like": 300,"tags": ["redis","json","backend","midware"]}
]
127.0.0.1:6379>
  • JSON.ARRINSERT
  • JSON.STRAPPEND

删

  • JSON.ARRPOP
  • JSON.ARRTRIM
  • JSON.CLEAR
  • JSON.DEL
  • JSON.FORGET

改

  • JSON.SET
  • JSON.MSET
  • JSON.NUMINCRBY
  • JSON.NUMMULTBY
  • JSON.MERGE
  • JSON.TOGGLE

查

  • JSON.ARRLEN
  • JSON.ARRINDEX
    127.0.0.1:6379> JSON.SET tom $ '["black","silver"]'
OK
127.0.0.1:6379>
127.0.0.1:6379>
127.0.0.1:6379>
127.0.0.1:6379> JSON.ARRINDEX tom $ '"black"'
1) (integer) 0127.0.0.1:6379> JSON.ARRINDEX tom $ '"silver"'
1) (integer) 1
  • JSON.DEBUG
  • JSON.DEBUG MEMORY
  • JSON.GET
  • JSON.MGET
  • JSON.OBJKEYS
  • JSON.OBJLEN
  • JSON.RESP (deprecated)
  • JSON.STRLEN
  • JSON.TYPE

redis json的clients

https://github.com/RedisJSON/RedisJSON?tab=readme-ov-file

redis json的使用场景 https://redis.io/docs/latest/develop/data-types/json/use_cases/

  • 从json中查询或搜索
  • 原子部分更新

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