SELECT failed: ERR invalid DB index BUG db is db0

[luoxun]

we are using laravel predis , but now we are having a problem as follow:
SELECT failed: ERR invalid DB index

I use command line to connect ,it works fine, I use db0, set and get work fine;
but in laravel predis ,when i use db 0, got a problem "SELECT failed: ERR invalid DB index
"; when I changed it into db1 ,db2,......,it's fine

here is my predis version
predis/predis v1.1.x-dev 0e17edb Flexible and feature-complete
and this is my redis version
redis-server redis_version:3.2.5

pls tell me how to fix this ,thx a lot

[nrk]

I don't use Laravel so I don't know what it does under the hood to configure Predis but setting database=0 (or "database" => 0 if using named arrays) in the connection parameters of Predis\Client works as expected. You should try using Predis alone and do the same to see if you get the same error response from Redis. If it works as expected, then this is not an issue related to Predis.

[JackSW]

@luoxun I just had a similar issue with laravel. When specifying the index, make sure to put the 0 in quotes, otherwise it just gets evaluated as false which ends up passing an empty string to the predis client.
REDIS_DATABASE = 0 gets turned into "database":"" and gives ERR invalid DB index
REDIS_DATABASE = "0" results in "database":"0" and works

[itsmylab]

I know I'm bumping a old thread, but for me setting REDIS_CACHE_DB to 0 sorted things out

[ybizeul]

Finally figured it out. not sure I understand though.

I'musing docker links, and naming my redis server : redis. That's an issue because of environment variable conflict, so I changed my redis server to redis-server.

But then I ried using just the url parameter as tcp://redis-server:6379 but kept getting the same error.

I finally commented out urland use hostand it works.

    'redis' => [

        'client' => env('REDIS_CLIENT', 'predis'),

        'options' => [
            'cluster' => env('REDIS_CLUSTER', 'predis'),
            'prefix' => env('REDIS_PREFIX', Str::slug(env('APP_NAME', 'laravel'), '_').'_database_'),
        ],

        'default' => [
            #'url' => 'tcp://redis-server:6379/',
            'host' => env('REDIS_HOST', 'redis-server'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', 6379),
            'database' => env('REDIS_DB', 0),
        ],
    ],

[gjae]

Finally figured it out. not sure I understand though.

I'musing docker links, and naming my redis server : redis. That's an issue because of environment variable conflict, so I changed my redis server to redis-server.

But then I ried using just the url parameter as tcp://redis-server:6379 but kept getting the same error.

I finally commented out urland use hostand it works.

    'redis' => [

        'client' => env('REDIS_CLIENT', 'predis'),

        'options' => [
            'cluster' => env('REDIS_CLUSTER', 'predis'),
            'prefix' => env('REDIS_PREFIX', Str::slug(env('APP_NAME', 'laravel'), '_').'_database_'),
        ],

        'default' => [
            #'url' => 'tcp://redis-server:6379/',
            'host' => env('REDIS_HOST', 'redis-server'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', 6379),
            'database' => env('REDIS_DB', 0),
        ],
    ],

THANKYOU!!! it work!

[osahady]

in .env file just add the following
REDIS_CACHE_DB=0

and it works

[PetengDedet]

Finally figured it out. not sure I understand though.
I'musing docker links, and naming my redis server : redis. That's an issue because of environment variable conflict, so I changed my redis server to redis-server.
But then I ried using just the url parameter as tcp://redis-server:6379 but kept getting the same error.
I finally commented out urland use hostand it works.

    'redis' => [

        'client' => env('REDIS_CLIENT', 'predis'),

        'options' => [
            'cluster' => env('REDIS_CLUSTER', 'predis'),
            'prefix' => env('REDIS_PREFIX', Str::slug(env('APP_NAME', 'laravel'), '_').'_database_'),
        ],

        'default' => [
            #'url' => 'tcp://redis-server:6379/',
            'host' => env('REDIS_HOST', 'redis-server'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', 6379),
            'database' => env('REDIS_DB', 0),
        ],
    ],

THANKYOU!!! it work!

You saved my day

[Mllexx]

in .env file just add the following
REDIS_CACHE_DB=0

and it works

This worked for me thanks.

[pratik-nickelfox]

I know I'm bumping a old thread, but for me setting REDIS_CACHE_DB to 0 sorted things out

Thank you so much.. :)

[MCKLtech]

+1 for adding REDIS_CACHE_DB equal to zero in the .env file (I'm using Heroku)

If anyone could explain why this would be the case, I'd be curous.

[rintoug]

in .env file just add the following REDIS_CACHE_DB=0

and it works

This worked for me in Laravel Version 7 and redislab free plan

[obipascal]

Setting the REDIS_CACHE_DB=1 or greater works fine!

[eskayamadeus]

Setting the REDIS_CACHE_DB=1 or greater works fine!

Brilliant. In my understanding, the value of REDIS_CACHE_DB just points to a name that should be used for the database. Therefore, any value at all should work, not just 0