below the list of your &quot;columns&quot; in the table structure you have a small table called &quot;Indexes&quot;. Every row is an index. Find there your unique index and drop it using &quot;drop&quot; symbol (red X). If you have it on more than one column then drop it and recreate without the column you don&#39;t want unique

Follow this steps:-

 1. Click **Structure** tab of table.
 2. Click **Index**(below the table).
 3. Click **Drop** for remove index(s).

![enter image description here][1]


  [1]: http://i.stack.imgur.com/tpRA6.png

In the tab structure below the table the indexes are listed. In some versions of PHPMyAdmin the index are listed only if you click on &quot;+Indexes&quot; which is easy to overlook.

ALTER TABLE `dbName`.`table` DROP INDEX `indexName`

I have a set of servers filled each with a bunch of files that can be gzipped.  The servers all have different numbers of cores.  How can I write a bash script to launch a gzip for each core and make sure the gzips are not zipping the same file?

Gzip with all cores

I&#39;m sure this has been asked a million times before but I can&#39;t find anything that works for me so I&#39;m asking again!

I just need a way of sending emails using ActionMailer in rails 3.  I have followed numerous tutorials including the Railscasts tutorial on the new ActionMailer and I can see the mails being generated but I don&#39;t receive them.

I have tried a bunch of different ways but they generally amount to configuring the following settings

    ActionMailer::Base.delivery_method = :smtp

    ActionMailer::Base.smtp_settings = {
      :address              =&gt; &quot;smtp.gmail.com&quot;,
      :port                 =&gt; &quot;587&quot;,
      :domain               =&gt; &quot;gmail.com&quot;,
      :user_name            =&gt; &quot;xxx@gmail.com&quot;,
      :password             =&gt; &quot;yyy&quot;,
      :authentication       =&gt; &quot;plain&quot;,
      :enable_starttls_auto =&gt; true
    }

I have tried the above code (with valid gmail details of course) in my config/environment.rb, config/environments/development.rb and currently have it in its own initialiser config/initialisers/setup_mail.rb

I have also tried with a few different smtp servers including Gmail and Sendgrid, adjusting the smtp settings accordingly but still nothing.  I can see the mail in the terminal and the development log and that&#39;s it.

Does anyone know of any other gotcha&#39;s that I may have missed that need to be setup for ActionMailer to work?  Failing that is there a way of getting more information about why the mails aren&#39;t being sent? I have 
    
    config.action_mailer.raise_delivery_errors = true

set in my config/development.rb but the development log still just shows the same as I see in the terminal.

For what it&#39;s worth, I am developing on a Ubuntu 10.04 laptop just in case there&#39;s any specific setup needed for that.

Many thanks

Sending mail with Rails 3 in development environment

I have a column in one of my tables which has been assigned an index. It is preventing me from having two of the same ID number. 

I am assuming the reason it is not letting me have two entries of the same ID is because it has been set to be Unique.

I am wondering how do I remove this rule so that I can insert the same ID number several times.

Cheers

phpMyAdmin Removing an index

I have a column in one of my tables which has been assigned an index. It is preventing me from having two of the same ID number.
I am assuming the reason it is not letting me have two entries of the same ID is because it has been set to be Unique.
I am wondering how do I remove this rule so that I can insert the same ID number several times.
Cheers

What happens if a clustered index is not unique? Can it lead to bad performance because inserted rows flow to an &quot;overflow&quot; page of some sorts?

Is it &quot;made&quot; unique and if so how? What is the best way to make it unique?

I am asking because I am currently using a clustered index to divide my table in logical parts, but the performance is so-so, and recently I got [the advice][1] to make my clustered indexes unique. I&#39;d like a second opinion on that.

  [1]: https://stackoverflow.com/questions/3733735/clustered-indexes-on-non-identity-columns-to-speed-up-bulk-inserts/4331661#4331661

Do clustered indexes have to be unique?

I&#39;ve got the following query but it doesn&#39;t seem to work.

    $q = $this-&gt;em-&gt;createQueryBuilder()
        -&gt;update(&#39;models\User&#39;, &#39;u&#39;)
        -&gt;set(&#39;u.username&#39;, $username)
        -&gt;set(&#39;u.email&#39;, $email)
        -&gt;where(&#39;u.id = ?1&#39;)
        -&gt;setParameter(1, $editId)
        -&gt;getQuery();
    $p = $q-&gt;execute();

This returns the following error message:

&gt; Fatal error: Uncaught exception
&gt; &#39;Doctrine\ORM\Query\QueryException&#39;
&gt; with message &#39;[Semantical Error] line
&gt; 0, col 38 near &#39;testusername WHERE&#39;:
&gt; Error: &#39;testusername&#39; is not defined.&#39;
&gt; in ...

I would be glad of any help

Doctrine 2: Update query with query builder

&gt; **Possible Duplicate:**  
&gt; [What is the etymology of &amp;#39;slug&amp;#39;?](https://stackoverflow.com/questions/4230846/what-is-the-etymology-of-slug)  

&lt;!-- End of automatically inserted text --&gt;

In CouchDB definitive guide the author used key &quot;slug&quot; in a document.

    {
       &quot;title&quot;: &quot;Hello World&quot;,
       &quot;slug&quot;: &quot;hello_world&quot;
    }

What does &quot;slug&quot; mean and why is it used?


What does &quot;slug&quot; mean

I am getting this error in wordpress phpMyadmin

    #145 - Table &#39;./DB_NAME/wp_posts&#39; is marked as crashed and should be repaired 

When I login to phpMyadmin, it says wp_posts is &quot;in use&quot;

My website is currently down because of this.

I googled this problem, but I don&#39;t see the &quot;repair&quot; button on phpMyadmin. Please let me know how to fix this. I am not sure where to issue PHP command. Please advise, my proficiency with PHP is very basic.

Table is marked as crashed and should be repaired

Let&#39;s say I insert the document.

    post = { some dictionary }
    mongo_id = mycollection.insert(post)

Now, let&#39;s say I want to add a field and update it. How do I do that? This doesn&#39;t seem to work.....

    post = mycollection.find_one({&quot;_id&quot;:mongo_id}) 
    post[&#39;newfield&#39;] = &quot;abc&quot;
    mycollection.save(post)

How do I update a Mongo document after inserting it?

I have a Dictionary below:

    colors = {
        &quot;blue&quot; : &quot;5&quot;,
        &quot;red&quot; : &quot;6&quot;,
        &quot;yellow&quot; : &quot;8&quot;,
    }

How do I index the first entry in the dictionary?

`colors[0]` will return a `KeyError` for obvious reasons.

How to index into a dictionary?

I am using 

    $(&#39;#list option&#39;).each(function(){
    //do stuff
    });

to loop over the options in a list.
I am wondering how I could get the index of the current loop?

as I dont want to have to have var i = 0; 
and inside the loop have i++;

jQuery .each() index?

I have a situation where I want to use the Meta options of `unique_together` to enforce a certain rule, here&#39;s the intermediary model:

&lt;!-- language: python --&gt;

    class UserProfileExtension(models.Model):
        extension = models.ForeignKey(Extension, unique=False)
        userprofile = models.ForeignKey(UserProfile, unique=False)
        user = models.ForeignKey(User, unique=False)  
        
        class Meta:
            unique_together = ((&quot;userprofile&quot;, &quot;extension&quot;),
                               (&quot;user&quot;, &quot;extension&quot;),
                               # How can I enforce UserProfile&#39;s Client 
                               # and Extension to be unique? This obviously
                               # doesn&#39;t work, but is this idea possible without
                               # creating another FK in my intermediary model 
                               (&quot;userprofile__client&quot;, &quot;extension&quot;))



and here&#39;s UserProfile:

&lt;!-- language: python --&gt;

    class UserProfile(models.Model):
        user = models.ForeignKey(User, unique=True)
        client = models.ForeignKey(Client)


Thanks.


Django Unique Together (with foreign keys)

Let me start by saying I have looked at many similar questions asked, but all of them relate to `Timestamp` and `DateTime` field type without indexing. At least that is my understanding. 

As we all know, there are certain advantages when it comes to DateTime. Putting them aside for a minute, and assuming table&#39;s engine is `InnoDB` with `10+ million records`, which query would perform faster when criteria is based on:

&gt;1. DateTime with index
&gt;2. int with index

In other words, it is better to store date and time as `DateTime` or UNIX timestamp in `int`? Keep in mind there is no need for any built-in MySQL functions to be used.

**Update**

Tested with MySQL 5.1.41 (64bit) and 10 million records, initial testing showed significant speed difference in favour of `int`. Two tables were used, `tbl_dt` with `DateTime` and `tbl_int` with `int` column. Few results:

    SELECT SQL_NO_CACHE COUNT(*) FROM `tbl_dt`;
    +----------+
    | COUNT(*) |
    +----------+
    | 10000000 |
    +----------+
    1 row in set (2 min 10.27 sec)

    SELECT SQL_NO_CACHE COUNT(*) FROM `tbl_int`;
    +----------+
    | count(*) |
    +----------+
    | 10000000 |
    +----------+
    1 row in set (25.02 sec)

    SELECT SQL_NO_CACHE COUNT(*) FROM `tbl_dt` WHERE `created` BETWEEN &#39;2009-01-30&#39; AND &#39;2009-12-30&#39;;
    +----------+
    | COUNT(*) |
    +----------+
    |   835663 |
    +----------+
    1 row in set (8.41 sec)

    SELECT SQL_NO_CACHE COUNT(*) FROM `tbl_int` WHERE `created` BETWEEN 1233270000 AND 1262127600;
    +----------+
    | COUNT(*) |
    +----------+
    |   835663 |
    +----------+
    1 row in set (1.56 sec)


I&#39;ll post another update with both fields in one table as suggested by [shantanuo][1].

**Update #2**

Final results after numerous server crashes :) Int type is significantly faster, no matter what query was run, the speed difference was more or less the same as results above.

&quot;Strange&quot; thing observed was execution time was more or less the same when two both field types are stored in the same table. It seems MySQL is smart enough to figure out when the values are the same when stored in both DateTime and int. Haven&#39;t found any documentation on the subject, therefore is just an observation.

 [1]: https://stackoverflow.com/users/139150/


MySQL Integer vs DateTime index

What is the easiest way to convert 

    [x1, x2, x3, ... , xN]

to

    [[x1, 2], [x2, 3], [x3, 4], ... , [xN, N+1]]


How to map/collect with index in Ruby?

Basically, I was taught on how to create a root password using the &quot;mysqladmin -u root -p password&quot; command, this was done all through the windows command editor. Now, the next process was to display the default databases (info. schema, mysql and test) which was achieved by using &quot;SHOW DATABASES;&quot;

But according to the book, we had to delete the redundant test file and the following error pops up: 

&gt;Error Dropping Database (Can&#39;t rmdir &#39;.test\&#39;, errno: 17)

The command put to use was `DROP DATABASE test;`

I am using MYSQL and PHPMYADMIN. Any help on how to drop the file with no errors? 
 

Error Dropping Database (Can&#39;t rmdir &#39;.test\&#39;, errno: 17)

I have my database properly set to UTF-8 and am dealing with a database containing Japanese characters.  If I do SELECT *... from the mysql command line, I properly see the Japanese characters.  When pulling data out of the database and displaying it on a webpage, I see it properly.

However, when viewing the table data in phpMyAdmin, I just see garbage text.  ie.

&#231;&#167;&#227;&#175;&#230;—&#165;&#230;œ&#172;&#230;–™&#231;†&#227;Œ&#229;&#165;&#189;&#227;&#227;&#167;&#227;™&#227;€‚&#230;—&#165;&#230;œ&#172;&#230;–™&#231;†&#227;‚...

How can I get phpMyAdmin to display the characters in Japanese?

The character encoding on the HTML page is set to UTF-8.

Edit:

I have tried an export of my database and opened up the .sql file in geany.  The characters are still garbled even though the encoding is set to UTF-8.  (However, doing a mysqldump of the database also shows garbled characters).

The character set is set correctly for the database and all tables (&#39;latin&#39; is not found anywhere in the file)

    CREATE DATABASE `japanese` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;

I have added the lines to my.cnf and restarted mysql but there is no change.  I am using Zend Framework to insert data into the database.

I am going to open a bounty for this question as I really want to figure this out.

How to display UTF-8 characters in phpMyAdmin?

I get the below error when pointing browser to phpMyAdmin

&gt; Cannot start session without errors, please check errors given in your PHP and/or webserver log file and configure your PHP installation properly.

I have checked everything and can&#39;t seem to figure out what the problem is. 

In my php.ini file I have:

    session.save_path = &quot;/var/lib/php/session&quot;

Permissions:  

    drwxr-xr-x  2 root apache 4096 Feb 16 04:47 session

Nothing seems to work. Even changing permission on session directory to 777.

Cannot start session without errors in phpMyAdmin

I want to start using table relations in a new project.

After some googling I got 2 tables set up as InnoDB:

The keys I want to link are

-&gt;users-&gt;userid (primary)
-&gt;sessions-&gt;userid (index)

The only thing that I don&#39;t understand in this process is what the different settings for &quot;On update&quot; and &quot;On delete&quot; do

The options here are:

- -- (nothing?)
- Cascade (???)
- Set Null (sets everything to null?)
- No action (well duh...)
- Restrict (???)

I basically want the data in sessions to be deleted when a user is completely deleted
This since the sessions will only be deleted when the expiration is detected by my session manager...

So if anyone can tell me what these options do it would be much appreciated.

Setting up table relations what do &quot;Cascade&quot;, &quot;Set Null&quot; and &quot;Restrict&quot; do?

I have an existing database using PHP, MySQL and phpMyAdmin.

When users become a member on my website, I need the system to create a unique membership number for them using a five digit number. for e.g 83773. I guess it is like generating a random password except I only want numbers for my members. This ID number has to be unique to each member. 

Would it be possible for me to set the primary key to auto_increment in my user table and set it to start at 10000 and then auto increment every time a member registers?

Also, is there a maximum number that the primary key ID number would go up to?

Is this a reliable and safe way to use the primary key ID number as a membership number?

Auto increment in phpmyadmin

Let&#39;s say I have a table of customer addresses:

&lt;!-- language: lang-none --&gt;

    +-----------------------+------------------------+
    |         CName         |      AddressLine       |
    +-----------------------+------------------------+
    |  John Smith           |  123 Nowheresville     |
    |  Jane Doe             |  456 Evergreen Terrace |
    |  John Smith           |  999 Somewhereelse     |
    |  Joe Bloggs           |  1 Second Ave          |
    +-----------------------+------------------------+

In the table, one customer like John Smith can have multiple addresses.
I need the `SELECT` query for this table to return only first row found where there are duplicates in &#39;CName&#39;. For this table it should return all rows except the 3rd (or 1st - any of those two addresses are okay but only one can be returned).

Is there a keyword I can add to the `SELECT` query to filter based on whether the server has already seen the column value before?

How to select only the first rows for each unique value of a column?

I have a JavaScript array like this:

    var myData=[&#39;237&#39;,&#39;124&#39;,&#39;255&#39;,&#39;124&#39;,&#39;366&#39;,&#39;255&#39;];

I need the array elements to be unique and sorted:

    myData[0]=&#39;124&#39;;
    myData[1]=&#39;237&#39;;
    myData[2]=&#39;255&#39;;
    myData[3]=&#39;366&#39;;

Even though the members of array **look like integers**, they&#39;re **not integers**, since I have already converted each to be string:

    var myData[0]=num.toString();
    //...and so on.

Is there any way to do all of these tasks in JavaScript?


Javascript array sort and unique

What is the best way (best as in the conventional way) of checking whether all elements in a list are unique?

My current approach using a `Counter` is:

    &gt;&gt;&gt; x = [1, 1, 1, 2, 3, 4, 5, 6, 2]
    &gt;&gt;&gt; counter = Counter(x)
    &gt;&gt;&gt; for values in counter.itervalues():
        	if values &gt; 1: 
                # do something

Can I do better? 

Checking if all elements in a list are unique

I remember reading in the spec once that both the `id` attribute and the `name` attribute share the same namespace and have to be unique. Henceforth I&#39;ve always tried to fulfill this requirement in my applications, dreading even to give the same `id` and `name` to the same element.

But lately I&#39;ve started working with ASP.NET MVC 3, and it (like PHP) can use the same `name` attribute on several input controls to form a collection of values at server-side. I tried to look up the relevant section in the spec - but failed to find it. Perhaps I have misunderstood something then, or read the wrong documentation?

How is it then? I want to produce as valid HTML as possible (both 4.01 and 5 in different apps). Can I use this trick without fear? Or would I be violating something and should better stick to unique values?

Does a name attribute have to be unique in a HTML document?

I&#39;m wondering what is the best way to display unique records from a has_many, through relationship in Rails3.

I have three models:

    class User &lt; ActiveRecord::Base
        has_many :orders
        has_many :products, :through =&gt; :orders
    end
    
    class Products &lt; ActiveRecord::Base
        has_many :orders
        has_many :users, :through =&gt; :orders
    end
    
    class Order &lt; ActiveRecord::Base
        belongs_to :user, :counter_cache =&gt; true 
        belongs_to :product, :counter_cache =&gt; true 
    end

Lets say I want to list all the products a customer has ordered on their show page. 

They may have ordered some products multiple times, so I&#39;m using counter_cache to display in descending rank order, based on the number of orders.

But, if they have ordered a product multiple times, I need to ensure that each product is only listed once.

    @products = @user.products.ranked(:limit =&gt; 10).uniq!
works when there are multiple order records for a product, but generates an error if a product has only been ordered once. (ranked is custom sort function defined elsewhere)

Another alternative is:

    @products = @user.products.ranked(:limit =&gt; 10, :select =&gt; &quot;DISTINCT(ID)&quot;)

I&#39;m not confident that I&#39;m on the right approach here. 

Has anyone else tackled this? What issues did you come up against? Where can I find out more about the difference between .unique! and DISTINCT()? 

What is the best way to generate a list of unique records through a has_many, through relationship?

Thanks




Content Type	Original Author	Original Content on Stackoverflow
Question	Samuel Meddows	View Question on Stackoverflow
Solution 1 - Database	Michael Tabolsky	View Answer on Stackoverflow
Solution 2 - Database	vineet	View Answer on Stackoverflow
Solution 3 - Database	Gunnar Bernstein	View Answer on Stackoverflow
Solution 4 - Database	saeid sayadi	View Answer on Stackoverflow

phpMyAdmin Removing an index

Database Problem Overview

Database Solutions

Solution 1 - Database

Solution 2 - Database

Solution 3 - Database

Solution 4 - Database

Sending mail with Rails 3 in development environment

Gzip with all cores

Attributions