The HGET
command in Redis is used to retrieve the value associated with a specific field from a hash stored at a key. In Golang, you might use this while implementing caching, session management, or any feature where you need to fetch particular data related to an object.
In this example, we connect to a local Redis instance and retrieve a field's value from a hash.
package main import ( "fmt" "github.com/go-redis/redis/v8" "context" ) var ctx = context.Background() func main() { rdb := redis.NewClient(&redis.Options{ Addr: "localhost:6379", Password: "", // no password set DB: 0, // use default DB }) err := rdb.HSet(ctx, "user:1000", "name", "John Doe").Err() if err != nil { panic(err) } val, err := rdb.HGet(ctx, "user:1000", "name").Result() if err != nil { panic(err) } fmt.Println("name", val) }
Here, we first set the "name" field for the hash at "user:1000" to be "John Doe". We then use HGet
to retrieve the name field, which prints out "John Doe".
HGet
. This will prevent your application from panicking in case the Redis server is not accessible or some other error occurs.HGet
returns two values - the result and an error. Ignoring the error return value is a common mistake which can lead to unexpected results.HGet
will return a nil error which can be mistaken for a connection or server problem. Ensure to check if the key or field exists before attempting to use HGet
.Q: What happens when the key or field does not exist?
A: The HGET
command will return a nil response without an error. This could sometimes be misconstrued as an error in connection or server. Always validate that your keys and fields exist before running the command.
Dragonfly is fully compatible with the Redis ecosystem and requires no code changes to implement.