Just use the `-n` argument to choose DB number. It available since Redis 2.4.2. 

    echo -n &quot;testing&quot; | redis-cli -n 4 -x set my_pass

or

    redis-cli -n 4 set my_pass testing


Launch the CLI by issuing command:

    redis-cli

Then use the following command:

    select &lt;db number&gt;

For example:

    select 4

The Effective Java has the following statement on unit testing singletons

&gt;Making a class a singleton can make it difficult to test its clients, as it’s impossible to substitute a mock implementation for a singleton unless it implements an interface that serves as its type.

Can anyone explain the why this is so ?

Singleton and unit testing

I search a way to access to the parent, parent function of a class without to call the parent... Hmmm, that sound a bit weird explanation so i will give an example: 

    class myclass
    {
      public function test() { return &#39;level 1&#39;; }
    }
    class myclass2 extends myclass
    {
      public function test() { return parent::test() . &#39;-level 2&#39;; }
    }
    class myclass3 extends myclass2
    {
      public function test() { return parent::test() . &#39;-level 3&#39;; }
    }
    $example = new myclass3();
    echo $example-&gt;test(); // should display &quot;level 1-level 2-level 3&quot;

I would like to display &quot;level 1-level 3&quot; then doing something like that:

    class myclass3 extends myclass2
    {
      public function test() { return parent::parent::test() . &#39;-level 3&#39;; }
    }


Do you have an idea how I can do this? (I am not allow to edit myclass and myclass2, they are part of a framework...)

parent::parent in PHP

dThe following works as expected. But how do I insert the data into forth database instead of default &quot;0&quot; from command prompt?

    # echo -n &quot;testing&quot; | /home/shantanu/redis-2.4.2/src/redis-cli -x set my_pass
    OK
    
    # echo -n &quot;testing&quot; | /home/shantanu/redis-2.4.2/src/redis-cli -x select 4; set my_pass
    (error) ERR wrong number of arguments for &#39;select&#39; command



using different database at redis command prompt

dThe following works as expected. But how do I insert the data into forth database instead of default "0" from command prompt?
<pre><code class="hljs language-shell"># echo -n "testing" | /home/shantanu/redis-2.4.2/src/redis-cli -x set my_pass
OK

# echo -n "testing" | /home/shantanu/redis-2.4.2/src/redis-cli -x select 4; set my_pass
(error) ERR wrong number of arguments for 'select' command
</code></pre>

I&#39;ve just install Redis succesfully using the instructions on the Quick Start guide on http://redis.io/topics/quickstart on my Ubuntu 10.10 server. I&#39;m running the service as  dameon (so it can be run by init.d)

The server is part of Rackspace Cluster with Internal and External IPs. The host is running on port 6379 (standard for Redis)

I&#39;ve added a row in the iptables to allow incoming connections from port 6379 as shown below:

     ACCEPT     tcp  --  anywhere             anywhere            tcp dpt:6379 

In my PHP code on another server, I&#39;m trying to connect to the new Redis server here:

    $this-&gt;load-&gt;helper(&quot;iredis&quot;);
		
    $hostname = &quot;IP ADDRESS HERE&quot;;
		
    $redis = new iRedis(array(&#39;hostname&#39; =&gt; $hostname, &#39;port&#39; =&gt; 6379));


Once I do this - I always get a connection refused. In my    redis.conf   file, I have the local bind command commented out, so it should be listening on more than the localhost IP. I can connect to the database on the local machine just not on another server. I&#39;ve tried the external and internal IPs with no luck.

Any suggestions on getting this to work?

Redis - Connect to Remote Server

Here is the thing - I want to store native JS (node.js) objects (flash sockets references) in redis under a certain key. When I do that with simple `client.set()` it&#39;s stored as a string. When I try to get value I get `[object Object]` - just a string.

Any chance to get this working? Here&#39;s my code:

      addSocket : function(sid, socket) {
        client.set(sid, socket);
      },
    
      getSocket : function(sid) {
        client.get(sid, function(err, reply) {
          // cant&#39;t get an object here. All I get is useless string
        });
      },

node.js store objects in redis

I working with node.js by expressjs &lt;br/&gt; I try to store an account to session. So, i try to test to use session with code in [expressjs](http://expressjs.com/guide.html)

    var RedisStore = require(&#39;connect-redis&#39;)(express);
    app.use(express.bodyParser());
    app.use(express.cookieParser());
    app.use(express.session({ secret: &quot;keyboard cat&quot;, store: new RedisStore }));

but I got error `Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED`. &lt;br/&gt; Please help me resolve this problem

Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED

I want to remove keys that match &quot;user*&quot;.

How do I do that in redis command line?

How do I remove keys?

Lets say I have a hash of a hash e.g.

    
    $data = {
        &#39;harry&#39; : {
    	     &#39;age&#39; : 25,
             &#39;weight&#39; : 75,
        },
        &#39;sally&#39; : {
            &#39;age&#39; : 25,
            &#39;weight&#39; : 75,
        }
    }

 1. What would the &#39;usual&#39; way to store such a data structure (or would you not?)
 2. Would you be able to directly get a value (e.g. get harry : age ?
 3.  Once stored could you directly change the value of a sub key (e.g. sally : weight = 100)

Content Type	Original Author	Original Content on Stackoverflow
Question	shantanuo	View Question on Stackoverflow
Solution 1 - Redis	miaout17	View Answer on Stackoverflow
Solution 2 - Redis	avichalp	View Answer on Stackoverflow

using different database at redis command prompt

Redis Problem Overview

Redis Solutions

Solution 1 - Redis

Solution 2 - Redis

parent::parent in PHP

Singleton and unit testing

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