Use [COALESCE][1]:

    SELECT COALESCE(field_a, field_b)

COALESCE is an ANSI standard function that returns the first non-null value from the list of columns specified, processing the columns from left to right.  So in the example, if `field_a` is null, `field_b` value will be displayed.  However, this function will return NULL if there is no non-null value from the columns specified.

It&#39;s supported on MySQL (I&#39;ve used it on 4.1), SQL Server (since v2000), Oracle 9i+...


  [1]: https://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html#function_coalesce

and another way to skin that cat (flexible for not just null comparisons)...

    select if(field_a is not null, field_a, field_b) from...



Yes, but it&#39;s just two parameters:

    IFNULL(field_a,field_b)

If `field_a` is not null, it will be returned. Otherwise `field_b` will be returned.

Reference: [IFNULL](http://dev.mysql.com/doc/refman/5.1/en/control-flow-functions.html#function_ifnull)

[For more examples][1]

MySQL IFNULL() With Syntax &amp; Examples

Syntax

The syntax of the IFNULL function is:

    IFNULL(expression_1,expression_2);

[examples][1]

       SELECT 
         name, IFNULL(businessphone, homephone) phone
     FROM
         users;

 

           #The above query return this result from users table
    
       +------------+-----------+----------+-----------
       | id        | name           | phone          |
       +------------+-----------+----------+-----------
       | 5         | Tommy Hill     | (541) 754-3009 |
       | 6         | John Smith     | (541) 754-3110 | 
       | 10        | Mark Greenspan | (541) 754-3111 | 
       | 11        | Kelvin Row     | (541) 754-3111 |
       +------------+-----------+----------+-----------


  [1]: https://www.tutsmake.com/mysql-ifnull-with-syntax-examples/

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Is there any risk, that in a newer version of Android, some of the default drawables are removed or resized? Or, affect in some negative way, the look of my app? Also, which of the drawables in the Android source code are considered &quot;stable&quot; and should be relied on?

I&#39;d rather not copy the drawables because I think that the look of the app should be consistent with the Android version used. So, for example, for version 1.6 it should use the default Android bitmaps for version 1.6.

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I have a select statement where I want to make the select conditional like this:

    IFNULL(field_a, field_a, field_b)

so that it checks field a. If a is null then the select would be field b.

Is that possible ?

MySQL IFNULL ELSE

I have a select statement where I want to make the select conditional like this:
<pre><code class="hljs language-scss">IFNULL(field_a, field_a, field_b)
</code></pre>
so that it checks field a. If a is null then the select would be field b.
Is that possible ?

Is there any nice command line MySQL client for windows? I mean a single exe that allows connecting and running a sample query. I&#39;ve googled and only could find big graphical environments like toad or mysql workbench. I need only a simple command line tool, where can  I download sth like this?

EDIT: I don&#39;t want to install the whole MySQL package on my PC. I know it&#39;s inside the mysql package but how do I download only this cmd line client. Because i don&#39;t need anything else.

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I&#39;m trying to track down a bug that&#39;s deleting rows in a `mysql` table. 

For the life of me I can&#39;t track it down in my `PHP` code, so I&#39;d like to work backwards by finding the actual mysql query that&#39;s removing the rows. 

I logged in to phpmyadmin, but can&#39;t find a way to view the history of past sql operations. 

Is there a way to view them in phpmyadmin?

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How do I know which configuration file is used by MySQL currently? Is there any command or something to find it out?


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How do I copy or clone or duplicate the data, structure,
and indices of a MySQL table to a new one?

This is what I&#39;ve found so far.

This will copy the data and the structure,
but not the indices:

    create table {new_table} select * from {old_table};

This will copy the structure and indices,
but not the data:

    create table {new_table} like {old_table};


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suppose I have this table

    id | cash 
    1    200
    2    301
    3    101
    4    700

and I want to return the first row in which the sum of all the previous cash is greater than a certain value: 

So for instance, if I want to return the first row in which the sum of all the previous cash is greater than 500, is should return to row 3

How do I do this using mysql statement?

using `WHERE SUM(cash) &gt; 500 `
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I have a form where a user can add multiple select boxes for multiple cities. The problem is that each newly generated select box needs to have a unique id. Can this be done is JavaScript?

UPDATE: here is the part of the form for selecting cities. Also note that i&#39;m using some php to fill in the cities when a specific state is selected.

    &lt;form id=&quot;form&quot; name=&quot;form&quot; method=&quot;post&quot; action=&quot;citySelect.php&quot;&gt;
	&lt;select id=&quot;state&quot; name=&quot;state&quot; onchange=&quot;getCity()&quot;&gt;
		&lt;option&gt;&lt;/option&gt;
		&lt;option value=&quot;1&quot;&gt;cali&lt;/option&gt;
		&lt;option value=&quot;2&quot;&gt;arizona&lt;/option&gt;
		&lt;option value=&quot;3&quot;&gt;texas&lt;/option&gt;
	&lt;/select&gt;
	&lt;select id=&quot;city&quot; name=&quot;city&quot; style=&quot;width:100px&quot;&gt;
		
	&lt;/select&gt;

		&lt;br/&gt;
	&lt;/form&gt;

Here is the javascript:


	$(&quot;#bt&quot;).click(function() {

    $(&quot;#form&quot;).append(
           &quot;&lt;select id=&#39;state&#39; name=&#39;state&#39; onchange=&#39;getCity()&#39;&gt;
               &lt;option&gt;&lt;/option&gt;
               &lt;option value=&#39;1&#39;&gt;cali&lt;/option&gt;
               &lt;option value=&#39;2&#39;&gt;arizona&lt;/option&gt;
               &lt;option value=&#39;3&#39;&gt;texas&lt;/option&gt;
            &lt;/select&gt;
            &lt;select id=&#39;city&#39; name=&#39;city&#39; style=&#39;width:100px&#39;&gt;&lt;/select&gt;&lt;br/&gt;&quot;
         );
    });

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How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.


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I have a list like this:

    Red
    Red
    Brown
    Yellow
    Green
    Green
    Brown
    Red
    Orange

I am trying to do a SELECT UNIQUE with LINQ, i.e. I want

    Red
    Brown
    Yellow
    Green
    Orange

    var uniqueColors = from dbo in database.MainTable
                       where dbo.Property == true
                       select dbo.Color.Name;

I then changed this to

    var uniqueColors = from dbo in database.MainTable
                       where dbo.Property == true
                       select dbo.Color.Name.Distinct();

with no success. The first `select` gets ALL the colors, so how do I modify it to only get the unique values?

If there is a better way of structuring this query, more than happy to go that route.

How do I go about editing it so I can have `.OrderBy( &quot;column name&quot; )` i.e. alphabetically by color name, so name property?

I keep getting a message:

&gt; The type arguments cannot be inferred from the usage. Try specifying the type arguments explicitly.


How can I do SELECT UNIQUE with LINQ?

I would like to add some style on a select box with the pseudo :after (to style my select box with 2 parts and without images). Here&#39;s the HTML:

    &lt;select name=&quot;&quot;&gt;
      &lt;option value=&quot;&quot;&gt;Test&lt;/option&gt;
    &lt;/select&gt;

And it doesn&#39;t work. I don&#39;t know why and I didn&#39;t find the answer in the W3C specs. Here&#39;s the CSS:

    select {
      -webkit-appearance: none;
      background: black;
      border: none;
      border-radius: 0;
      color: white;
    }

    select:after {
      content: &quot; &quot;;
      display: inline-block;
      width: 24px; height: 24px;
      background: blue;
    }

So is it normal or is there a trick?

problem with &lt;select&gt; and :after with CSS in WebKit

In SQLite, how can I select records where `some_column` is empty?  
Empty counts as both `NULL` and `&quot;&quot;`.

Content Type	Original Author	Original Content on Stackoverflow
Question	mcgrailm	View Question on Stackoverflow
Solution 1 - Mysql	OMG Ponies	View Answer on Stackoverflow
Solution 2 - Mysql	user3590489	View Answer on Stackoverflow
Solution 3 - Mysql	Matt	View Answer on Stackoverflow
Solution 4 - Mysql	Developer	View Answer on Stackoverflow

MySQL IFNULL ELSE

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