Redis Command: HGET - BigBoxCode

Summary

Command Name	HGET
Usage	Get single hash field value
Group	hash
ACL Category	@read @hash @fast
Time Complexity	O(1)
Flag	READONLY FAST
Arity	3

Signature

HGET <key> <field>

Usage

Get the value of a single field of a hash. This is the simplest command for getting the value from a hash, but only one field can be fetched from the hash.

Notes

HMGET supports multiple fields, and HGETALL returns all data of a hash. So you can use these if these commands serve your purpose.

Arguments

Parameter	Description	Name	Type
<key>	Name of the key of the hash	key	key
<field>	Name of the field	field	string

Return Value

Return value	Case for the return value	Type
Field value	On successful we get the value saved for the field	string
(nil)	If the key(for the hash) does not exist, or the field is not present in the hash	null
error	If applied to wrong data type	error

Notes

If the command is applied to a key that is not a hash, then the following error is returned-
(error) WRONGTYPE Operation against a key holding the wrong kind of value

Examples

Here are a few examples of the usage examples of the Redis HGET command-

# Redis HGET command examples

# Set some has fields usign HSET
127.0.0.1:6379> hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
(integer) 5

# Check zip field of the hash
127.0.0.1:6379> hget customer:99:address zip
"65616"

# Check state field of the hash
127.0.0.1:6379> hget customer:99:address state
"Mississippi"

# Try to get value of a field that does not exist
# We get (nil)
127.0.0.1:6379> hget customer:99:address nonexistingfield
(nil)

# Try to get field value from a non existing hash
# We get (nil)
127.0.0.1:6379> hget nonexistinghash somefield
(nil)

# Set a string value
127.0.0.1:6379> set bigboxstr "some string in the box"
OK

# Try to use the HGET on a string type of key
# We get an error
127.0.0.1:6379> hget bigboxstr somefield
(error) WRONGTYPE Operation against a key holding the wrong kind of value

Notes

If the key does not exist or the field does not exist then the command returns Null (nil)

Code Implementations

Redis HGET command example implementation in Golang, NodeJS, Java, C#, PHP, Python, Ruby-

Go
NodeJS

Python
Ruby

// Redis HGET command example in Golang

package main

import (
	"context"
	"fmt"

	"github.com/redis/go-redis/v9"
)

var rdb *redis.Client
var ctx context.Context

func init() {
	rdb = redis.NewClient(&redis.Options{
		Addr:     "localhost:6379",
		Username: "default",
		Password: "",
		DB:       0,
	})

	ctx = context.Background()
}

func main() {

	/**
	* Set some has fields usign HSET
	*
	* Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
	* Result: (integer) 5
	 */
	hsetResult, err := rdb.HSet(ctx, "customer:99:address",
		"street", "2855 W 76 Country Blvd",
		"city", "Branson",
		"state", "Mississippi",
		"zip", "65616",
		"country", "United States",
	).Result()

	if err != nil {
		fmt.Println("Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Error: " + err.Error())
	}

	fmt.Println("Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: ", hsetResult)

	/**
	* Check zip field of the hash
	*
	* Command: hget customer:99:address zip
	* Result: "65616"
	 */
	hgetResult, err := rdb.HGet(ctx, "customer:99:address", "zip").Result()

	if err != nil {
		fmt.Println("Command: hget customer:99:address zip | Error: " + err.Error())
	}

	fmt.Println("Command: hget customer:99:address zip | Result: " + hgetResult)

	/**
	* Check state field of the hash
	*
	* Command: hget customer:99:address state
	* Result: "Mississippi"
	 */
	hgetResult, err = rdb.HGet(ctx, "customer:99:address", "state").Result()

	if err != nil {
		fmt.Println("Command: hget customer:99:address state | Error: " + err.Error())
	}

	fmt.Println("Command: hget customer:99:address state | Result: " + hgetResult)

	/**
	* Try to get value of a field that does not exist
	* We get (nil)
	*
	* Command: hget customer:99:address nonexistingfield
	* Result: (nil)
	 */
	hgetResult, err = rdb.HGet(ctx, "customer:99:address", "nonexistingfield").Result()

	if err != nil {
		fmt.Println("Command: hget customer:99:address nonexistingfield | Error: " + err.Error())
	}

	fmt.Println("Command: hget customer:99:address nonexistingfield | Result: " + hgetResult)

	/**
	* Try to get field value from a non existing hash
	* We get (nil)
	*
	* Command: hget nonexistinghash somefield
	* Result: (nil)
	 */
	hgetResult, err = rdb.HGet(ctx, "nonexistinghash", "somefield").Result()

	if err != nil {
		fmt.Println("Command: hget nonexistinghash somefield | Error: " + err.Error())
	}

	fmt.Println("Command: hget nonexistinghash somefield | Result: " + hgetResult)

	/**
	* Set a string value
	*
	* Command: set bigboxstr "some string in the box"
	* Result: OK
	 */
	setResult, err := rdb.Set(ctx, "bigboxstr", "some string in the box", 0).Result()

	if err != nil {
		fmt.Println("Command: set bigboxstr "some string in the box" | Error: " + err.Error())
	}

	fmt.Println("Command: set bigboxstr "some string in the box" | Result: " + setResult)

	/**
	* Try to use the HGET on a string type of key
	* We get an error
	*
	* Command: hget bigboxstr somefield
	* Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
	 */
	hgetResult, err = rdb.HGet(ctx, "bigboxstr", "somefield").Result()

	if err != nil {
		fmt.Println("Command: hget bigboxstr somefield | Error: " + err.Error())
	}

	fmt.Println("Command: hget bigboxstr somefield | Result: " + hgetResult)

}

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result:  5

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Error: redis: nil
Command: hget customer:99:address nonexistingfield | Result:

Command: hget nonexistinghash somefield | Error: redis: nil
Command: hget nonexistinghash somefield | Result:

Command: set bigboxstr "some string in the box" | Result: OK

Command: hget bigboxstr somefield | Error: WRONGTYPE Operation against a key holding the wrong kind of value
Command: hget bigboxstr somefield | Result:

Notes

Use “HGet” method from redis-go module.
Signature of the method is-
HSet(ctx context.Context, key string, values ...interface{}) *IntCmd

// Redis HGET command example in JavaScript(NodeJS)

import { createClient } from "redis";

// Create redis client
const redisClient = createClient({
  url: "redis://default:@localhost:6379",
});

redisClient.on("error", (err) =>
  console.log("Error while connecting to Redis", err)
);

// Connect Redis client
await redisClient.connect();

/**
 * Set some has fields usign HSET
 *
 * Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
 * Result: (integer) 5
 */
let commandResult = await redisClient.hSet("customer:99:address", {
  street: "2855 W 76 Country Blvd",
  city: "Branson",
  state: "Mississippi",
  zip: "65616",
  country: "United States",
});

console.log(
  'Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: ' +
    commandResult
);

/**
 * Check zip field of the hash
 *
 * Command: hget customer:99:address zip
 * Result: "65616"
 */
commandResult = await redisClient.hGet("customer:99:address", "zip");

console.log("Command: hget customer:99:address zip | Result: " + commandResult);

/**
 * Check state field of the hash
 *
 * Command: hget customer:99:address state
 * Result: "Mississippi"
 */
commandResult = await redisClient.hGet("customer:99:address", "state");

console.log(
  "Command: hget customer:99:address state | Result: " + commandResult
);

/**
 * Try to get value of a field that does not exist
 * We get (nil)
 *
 * Command: hget customer:99:address nonexistingfield
 * Result: (nil)
 */
commandResult = await redisClient.hGet(
  "customer:99:address",
  "nonexistingfield"
);

console.log(
  "Command: hget customer:99:address nonexistingfield | Result: " +
    commandResult
);

/**
 * Try to get field value from a non existing hash
 * We get (nil)
 *
 * Command: hget nonexistinghash somefield
 * Result: (nil)
 */
commandResult = await redisClient.hGet("nonexistinghash", "somefield");

console.log(
  "Command: hget nonexistinghash somefield | Result: " + commandResult
);

/**
 * Set a string value
 *
 * Command: set bigboxstr "some string in the box"
 * Result: OK
 */
commandResult = await redisClient.set("bigboxstr", "some string in the box");

console.log(
  'Command: set bigboxstr "some string in the box" | Result: ' + commandResult
);

/**
 * Try to use the HGET on a string type of key
 * We get an error
 *
 * Command: hget bigboxstr somefield
 * Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
 */
try {
  commandResult = await redisClient.hGet("bigboxstr", "somefield");

  console.log("Command: hget bigboxstr somefield | Result: " + commandResult);
} catch (err) {
  console.log("Command: hget bigboxstr somefield | Error: ", err);
}

process.exit(0);

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: 5

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Result: null

Command: hget nonexistinghash somefield | Result: null

Command: set bigboxstr "some string in the box" | Result: OK
Command: hget bigboxstr somefield | Error:  [ErrorReply: WRONGTYPE Operation against a key holding the wrong kind of value]

Notes

Use the function “hGet” of node-redis.

Signature of the method-
function hGet(key: RedisCommandArgument, field: RedisCommandArgument)

// Redis HGET Command example in Java

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

import java.util.HashMap;
import java.util.Map;

public class Hget {
    public static void main(String[] args) {
        JedisPool jedisPool = new JedisPool("localhost", 6379);

        try (Jedis jedis = jedisPool.getResource()) {

            /**
             * Set some has fields usign HSET
             *
             * Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
             * Result: (integer) 5
             */
            Map<String, String> hashData = new HashMap<>() {{
                put("street", "2855 W 76 Country Blvd");
                put("city", "Branson");
                put("state", "Mississippi");
                put("zip", "65616");
                put("country", "United States");
            }};
            long hsetResult = jedis.hset("customer:99:address", hashData);

            System.out.println("Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: " + hsetResult);

            /**
             * Check zip field of the hash
             *
             * Command: hget customer:99:address zip
             * Result: "65616"
             */
            String hgetResult = jedis.hget("customer:99:address", "zip");

            System.out.println("Command: hget customer:99:address zip | Result: " + hgetResult);

            /**
             * Check state field of the hash
             *
             * Command: hget customer:99:address state
             * Result: "Mississippi"
             */
            hgetResult = jedis.hget("customer:99:address", "state");

            System.out.println("Command: hget customer:99:address state | Result: " + hgetResult);

            /**
             * Try to get value of a field that does not exist
             * We get (nil)
             *
             * Command: hget customer:99:address nonexistingfield
             * Result: (nil)
             */
            hgetResult = jedis.hget("customer:99:address", "nonexistingfield");

            System.out.println("Command: hget customer:99:address nonexistingfield | Result: " + hgetResult);

            /**
             * Try to get field value from a non existing hash
             * We get (nil)
             *
             * Command: hget nonexistinghash somefield
             * Result: (nil)
             */
            hgetResult = jedis.hget("nonexistinghash", "somefield");

            System.out.println("Command: hget nonexistinghash somefield | Result: " + hgetResult);

            /**
             * Set a string value
             *
             * Command: set bigboxstr "some string in the box"
             * Result: OK
             */
            String setResult = jedis.set("bigboxstr", "some string in the box");

            System.out.println("Command: set bigboxstr "some string in the box" | Result: " + setResult);

            /**
             * Try to use the HGET on a string type of key
             * We get an error
             *
             * Command: hget bigboxstr somefield
             * Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
             */
            try {
                hgetResult = jedis.hget("bigboxstr", "somefield");

                System.out.println("Command: hget bigboxstr somefield | Result: " + hgetResult);
            } catch (Exception e) {
                System.out.println("Command: hget bigboxstr somefield | Error: " + e.getMessage());
            }

        }

        jedisPool.close();
    }
}

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: 5

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Result: null

Command: hget nonexistinghash somefield | Result: null

Command: set bigboxstr "some string in the box" | Result: OK
Command: hget bigboxstr somefield | Error: WRONGTYPE Operation against a key holding the wrong kind of value

Notes

Use method “hget” from Jedis package.
The signature of the method is-
public String hget(final String key, final String field)

// Redis HGET command examples in C#

using StackExchange.Redis;

namespace Hget
{
    internal class Program
    {
        static void Main(string[] args)
        {
            ConnectionMultiplexer redis = ConnectionMultiplexer.Connect("localhost");
            IDatabase rdb = redis.GetDatabase();

            /**
             * Set some has fields usign HSET
             *
             * Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
             * Result: (integer) 5
             */
            HashEntry[] hashData = new HashEntry[] {
                new HashEntry("street", "2855 W 76 Country Blvd"),
                new HashEntry("city", "Branson"),
                new HashEntry("state", "Mississippi"),
                new HashEntry("zip", "65616"),
                new HashEntry("country", "United States")
            };
            rdb.HashSet("customer:99:address", hashData);

            Console.WriteLine("Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"");

            /**
             * Check zip field of the hash
             *
             * Command: hget customer:99:address zip
             * Result: "65616"
             */
            RedisValue hgetResult = rdb.HashGet("customer:99:address", "zip");
            Console.WriteLine("Command: hget customer:99:address zip | Result: " + hgetResult);

            /**
             * Check state field of the hash
             *
             * Command: hget customer:99:address state
             * Result: "Mississippi"
             */
            hgetResult = rdb.HashGet("customer:99:address", "state");

            Console.WriteLine("Command: hget customer:99:address state | Result: " + hgetResult);

            /**
             * Try to get value of a field that does not exist
             * We get (nil)
             *
             * Command: hget customer:99:address nonexistingfield
             * Result: (nil)
             */
            hgetResult = rdb.HashGet("customer:99:address", "nonexistingfield");

            Console.WriteLine("Command: hget customer:99:address nonexistingfield | Result: " + hgetResult);

            /**
             * Try to get field value from a non existing hash
             * We get (nil)
             *
             * Command: hget nonexistinghash somefield
             * Result: (nil)
             */
            hgetResult = rdb.HashGet("nonexistinghash", "somefield");

            Console.WriteLine("Command: hget nonexistinghash somefield | Result: " + hgetResult);


            /**
             * Set a string value
             *
             * Command: set bigboxstr "some string in the box"
             * Result: OK
             */
            bool setResult = rdb.StringSet("bigboxstr", "some string in the box");

            Console.WriteLine("Command: set bigboxstr "some string in the box" | Result: " + setResult);

            /**
             * Try to use the HGET on a string type of key
             * We get an error
             *
             * Command: hget bigboxstr somefield
             * Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
             */
            try
            {
                hgetResult = rdb.HashGet("bigboxstr", "somefield");

                Console.WriteLine("Command: hget bigboxstr somefield | Result: " + hgetResult);
            }
            catch (Exception e)
            {
                Console.WriteLine("Command: hget bigboxstr somefield | Error: " + e.Message);
            }
        }
    }
}

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Result:

Command: hget nonexistinghash somefield | Result:

Command: set bigboxstr "some string in the box" | Result: True
Command: hget bigboxstr somefield | Error: WRONGTYPE Operation against a key holding the wrong kind of value

Notes

Use the method “HashGet” from StackExchange.Redis.
Signatures of the method are-
RedisValue HashGet(RedisKey key, RedisValue hashField, CommandFlags flags = CommandFlags.None)

<?php
// Redis HGET command example in PHP

require 'vendor/autoload.php';

// Connect to Redis
$redisClient = new PredisClient([
    'scheme' => 'tcp',
    'host' => 'localhost',
    'port' => 6379,
]);


/**
 * Set some has fields usign HSET
 *
 * Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
 * Result: (integer) 5
 */

$commandResult = $redisClient->hset("customer:99:address",
    "street", "2855 W 76 Country Blvd",
    "city", "Branson",
    "state", "Mississippi",
    "zip", "65616",
    "country", "United States",
);

echo "Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: " . $commandResult . "n";

/**
 * Check zip field of the hash
 *
 * Command: hget customer:99:address zip
 * Result: "65616"
 */
$commandResult = $redisClient->hget("customer:99:address", "zip");

echo "Command: hget customer:99:address zip | Result: " . $commandResult . "n";

/**
 * Check state field of the hash
 *
 * Command: hget customer:99:address state
 * Result: "Mississippi"
 */
$commandResult = $redisClient->hget("customer:99:address", "state");

echo "Command: hget customer:99:address state | Result: " . $commandResult . "n";

/**
 * Try to get value of a field that does not exist
 * We get (nil)
 *
 * Command: hget customer:99:address nonexistingfield
 * Result: (nil)
 */
$commandResult = $redisClient->hget("customer:99:address", "nonexistingfield");

echo "Command: hget customer:99:address nonexistingfield | Result: " . $commandResult . "n";

/**
 * Try to get field value from a non existing hash
 * We get (nil)
 *
 * Command: hget nonexistinghash somefield
 * Result: (nil)
 */
$commandResult = $redisClient->hget("nonexistinghash", "somefield");

echo "Command: hget nonexistinghash somefield | Result: " . $commandResult . "n";

/**
 * Set a string value
 *
 * Command: set bigboxstr "some string in the box"
 * Result: OK
 */
$commandResult = $redisClient->set("bigboxstr", "some string in the box");

echo "Command: set bigboxstr "some string in the box" | Result: " . $commandResult . "n";

/**
 * Try to use the HGET on a string type of key
 * We get an error
 *
 * Command: hget bigboxstr somefield
 * Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
 */
try {
    $commandResult = $redisClient->hget("bigboxstr", "somefield");

    echo "Command: hget bigboxstr somefield | Result: " . $commandResult . "n";
} catch (Exception $e) {
    echo "Command: hget bigboxstr somefield | Error: " . $e->getMessage() . "n";
}

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: 5

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Result:

Command: hget nonexistinghash somefield | Result:

Command: set bigboxstr "some string in the box" | Result: OK
Command: hget bigboxstr somefield | Error: WRONGTYPE Operation against a key holding the wrong kind of value

Notes

Use the method “hget” of predis.

Signature of the method is-
hget(string $key, string $field): string|null

# Redis HGET command example in Python

import redis
import time

# Create Redis client
redisClient = redis.Redis(host='localhost', port=6379,
                          username='default', password='',
                          decode_responses=True)


# Set some has fields usign HSET
# Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
# Result: (integer) 5
commandResult = redisClient.hset("customer:99:address", mapping= {
    "street": "2855 W 76 Country Blvd",
    "city": "Branson",
    "state": "Mississippi",
    "zip": "65616",
    "country": "United States",
})

print("Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: {}".format(commandResult))

# Check zip field of the hash
# Command: hget customer:99:address zip
# Result: "65616"
commandResult = redisClient.hget("customer:99:address", "zip")

print("Command: hget customer:99:address zip | Result: {}".format(commandResult))

# Check state field of the hash
# Command: hget customer:99:address state
# Result: "Mississippi"
commandResult = redisClient.hget("customer:99:address", "state")

print("Command: hget customer:99:address state | Result: {}".format(commandResult))

# Try to get value of a field that does not exist
# We get (nil)
# Command: hget customer:99:address nonexistingfield
# Result: (nil)
commandResult = redisClient.hget("customer:99:address", "nonexistingfield")

print("Command: hget customer:99:address nonexistingfield | Result: {}".format(commandResult))

# Try to get field value from a non existing hash
# We get (nil)
# Command: hget nonexistinghash somefield
# Result: (nil)
commandResult = redisClient.hget("nonexistinghash", "somefield")

print("Command: hget nonexistinghash somefield | Result: {}".format(commandResult))

# Set a string value
# Command: set bigboxstr "some string in the box"
# Result: OK
commandResult = redisClient.set("bigboxstr", "some string in the box")

print("Command: set bigboxstr "some string in the box" | Result: {}".format(commandResult))

# Try to use the HGET on a string type of key
# We get an error
# Command: hget bigboxstr somefield
# Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
try:
    commandResult = redisClient.hget("bigboxstr", "somefield")

    print("Command: hget bigboxstr somefield | Result: {}".format(commandResult))
except Exception as error:
    print("Command: hget bigboxstr somefield | Error: ", error , "n")

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: 5

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Result: None

Command: hget nonexistinghash somefield | Result: None

Command: set bigboxstr "some string in the box" | Result: True
Command: hget bigboxstr somefield | Error:  WRONGTYPE Operation against a key holding the wrong kind of value

Notes

Use method “hget” from redis-py.
Signature of the method is –
def hget(self, name: str, key: str)

# Redis HGET command example in Ruby

require 'redis'

redis = Redis.new(host: "localhost", port: 6379)


# Set some has fields usign HSET
# Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States"
# Result: (integer) 5
commandResult = redis.hset("customer:99:address", {
    "street" => "2855 W 76 Country Blvd",
    "city" => "Branson",
    "state" => "Mississippi",
    "zip" => "65616",
    "country" => "United States",
})

print("Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: ", commandResult, "n")

# Check zip field of the hash
# Command: hget customer:99:address zip
# Result: "65616"
commandResult = redis.hget("customer:99:address", "zip")

print("Command: hget customer:99:address zip | Result: ", commandResult, "n")

# Check state field of the hash
# Command: hget customer:99:address state
# Result: "Mississippi"
commandResult = redis.hget("customer:99:address", "state")

print("Command: hget customer:99:address state | Result: ", commandResult, "n")

# Try to get value of a field that does not exist
# We get (nil)
# Command: hget customer:99:address nonexistingfield
# Result: (nil)
commandResult = redis.hget("customer:99:address", "nonexistingfield")

print("Command: hget customer:99:address nonexistingfield | Result: ", commandResult, "n")

# Try to get field value from a non existing hash
# We get (nil)
# Command: hget nonexistinghash somefield
# Result: (nil)
commandResult = redis.hget("nonexistinghash", "somefield")

print("Command: hget nonexistinghash somefield | Result: ", commandResult, "n")

# Set a string value
# Command: set bigboxstr "some string in the box"
# Result: OK
commandResult = redis.set("bigboxstr", "some string in the box")

print("Command: set bigboxstr "some string in the box" | Result: ", commandResult, "n")

# Try to use the HGET on a string type of key
# We get an error
# Command: hget bigboxstr somefield
# Result: (error) WRONGTYPE Operation against a key holding the wrong kind of value
begin
    commandResult = redis.hget("bigboxstr", "somefield")

    print("Command: hget bigboxstr somefield | Result: ", commandResult, "n")
rescue => e
    print("Command: hget bigboxstr somefield | Error: ", e, "n")
end

Output:

Command: hset customer:99:address street "2855 W 76 Country Blvd" city Branson state Mississippi zip 65616 country "United States" | Result: 5

Command: hget customer:99:address zip | Result: 65616

Command: hget customer:99:address state | Result: Mississippi

Command: hget customer:99:address nonexistingfield | Result: 

Command: hget nonexistinghash somefield | Result: 

Command: set bigboxstr "some string in the box" | Result: OK
Command: hget bigboxstr somefield | Error: WRONGTYPE Operation against a key holding the wrong kind of value

Notes

Use method “hget” from the redis-rb.
Signature of the method is-
# @param [String] key # @param [String] field # @return [String] def hget(key, field)

Source Code

Use the following links to get the source code used in this article-

Source Code of	Source Code Link
Command Examples	GitHub
Golang Implementation	GitHub
NodeJS Implementation	GitHub
Java Implementation	GitHub
C# Implementation	GitHub
PHP Implementation	GitHub
Python Implementation	GitHub
Ruby Implementation	GitHub

Related Commands

Command	Details
HSETNX	Command Details
HMGET	Command Details
HGETALL	Command Details
HSET	Command Details

Summary

Signature

Usage

Arguments

Return Value

Examples

Code Implementations

Source Code

Related Commands

Leave a Comment Cancel reply