How to use Redis special data type Geospatial
Redis special data type Geospatial geographic space
This was launched in redis version 3.2. It can be used to calculate geographical location information, the distance between two places, the people around it, etc. .
1. geoadd
Add the specified geospatial location (latitude, longitude, name) to the specified key.
Here you can use some online latitude and longitude query tools to obtain data.
geoadd china:city 121.472644 31.231706 shanghai geoadd china:city 120.619585 31.299379 suzhou geoadd china:city 116.405285 39.904989 beijing geoadd china:city 113.280637 23.125178 guangzhou 113.26197 23.10379 haizhuqu
Go to the key china:city
and add the longitude and latitude of 5 places: Shanghai, Suzhou, Beijing, Guangzhou, and Haizhu District of Guangzhou.
2. geopos
Return the positions (longitude and latitude) of all given position elements from the key.
geopos china:city suzhou shanghai
Returns the coordinates of the location.
3. geodist
Returns the distance between two given positions.
If one of the two positions does not exist, the command returns a null value.
The parameter unit that specifies the unit must be one of the following units:
m means the unit is meters (default).
km means the unit is kilometers.
mi means the unit is miles.
ft means feet.
geodist china:city suzhou shanghai km
4. Georadius
With the given longitude and latitude as the center, return the position element contained in the key, and the center All position elements whose distance does not exceed the given maximum distance.
georadius china:city 121.49295 31.22337 30 km
I am looking for cities within 30km with the coordinates 121.49295 31.22337 of Shanghai Huangpu District as the center.
Further away, within 100km, you can also find suzhou
, add withdist
to show the distance.
Added withcoord
can return the latitude and longitude.
plus count
returns only the amount I specify.
georadius china:city 121.49295 31.22337 100 km withdist withcoord count 1
5. georadiusbymember
This command is the same as the georadius command. It can find elements within the specified range.
But here we do not specify the center point coordinates, but specify which element is the center point.
georadiusbymember china:city suzhou 100 km withdist
Here, taking element suzhou
as the center point, find other elements within 100km on Friday.
6. geohash
One or more positional elements, represented by hash.
geohash china:city suzhou shanghai
Returns an 11-character Geohash string, a string representing the current longitude and latitude, which is a different form, converting the two-dimensional longitude and latitude into a one-dimensional String.
If the two strings in the structure above are closer, the distance between the two positions will be closer. This is all you need to know.
The underlying principle of geo is still zset. We can use the zset command to operate geo, such as removing cities from geo.
zrem china:city haizhuqu
The above is the detailed content of How to use Redis special data type Geospatial. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

Redis cluster mode deploys Redis instances to multiple servers through sharding, improving scalability and availability. The construction steps are as follows: Create odd Redis instances with different ports; Create 3 sentinel instances, monitor Redis instances and failover; configure sentinel configuration files, add monitoring Redis instance information and failover settings; configure Redis instance configuration files, enable cluster mode and specify the cluster information file path; create nodes.conf file, containing information of each Redis instance; start the cluster, execute the create command to create a cluster and specify the number of replicas; log in to the cluster to execute the CLUSTER INFO command to verify the cluster status; make

To read a queue from Redis, you need to get the queue name, read the elements using the LPOP command, and process the empty queue. The specific steps are as follows: Get the queue name: name it with the prefix of "queue:" such as "queue:my-queue". Use the LPOP command: Eject the element from the head of the queue and return its value, such as LPOP queue:my-queue. Processing empty queues: If the queue is empty, LPOP returns nil, and you can check whether the queue exists before reading the element.

How to clear Redis data: Use the FLUSHALL command to clear all key values. Use the FLUSHDB command to clear the key value of the currently selected database. Use SELECT to switch databases, and then use FLUSHDB to clear multiple databases. Use the DEL command to delete a specific key. Use the redis-cli tool to clear the data.

On CentOS systems, you can limit the execution time of Lua scripts by modifying Redis configuration files or using Redis commands to prevent malicious scripts from consuming too much resources. Method 1: Modify the Redis configuration file and locate the Redis configuration file: The Redis configuration file is usually located in /etc/redis/redis.conf. Edit configuration file: Open the configuration file using a text editor (such as vi or nano): sudovi/etc/redis/redis.conf Set the Lua script execution time limit: Add or modify the following lines in the configuration file to set the maximum execution time of the Lua script (unit: milliseconds)

There are two types of Redis data expiration strategies: periodic deletion: periodic scan to delete the expired key, which can be set through expired-time-cap-remove-count and expired-time-cap-remove-delay parameters. Lazy Deletion: Check for deletion expired keys only when keys are read or written. They can be set through lazyfree-lazy-eviction, lazyfree-lazy-expire, lazyfree-lazy-user-del parameters.

Use the Redis command line tool (redis-cli) to manage and operate Redis through the following steps: Connect to the server, specify the address and port. Send commands to the server using the command name and parameters. Use the HELP command to view help information for a specific command. Use the QUIT command to exit the command line tool.

Redis counter is a mechanism that uses Redis key-value pair storage to implement counting operations, including the following steps: creating counter keys, increasing counts, decreasing counts, resetting counts, and obtaining counts. The advantages of Redis counters include fast speed, high concurrency, durability and simplicity and ease of use. It can be used in scenarios such as user access counting, real-time metric tracking, game scores and rankings, and order processing counting.

In Debian systems, readdir system calls are used to read directory contents. If its performance is not good, try the following optimization strategy: Simplify the number of directory files: Split large directories into multiple small directories as much as possible, reducing the number of items processed per readdir call. Enable directory content caching: build a cache mechanism, update the cache regularly or when directory content changes, and reduce frequent calls to readdir. Memory caches (such as Memcached or Redis) or local caches (such as files or databases) can be considered. Adopt efficient data structure: If you implement directory traversal by yourself, select more efficient data structures (such as hash tables instead of linear search) to store and access directory information
