building a query of a custom post type and custom field.

You are right! The question is a little vague! ??

Maybe what you need is explained in the Codex under query_posts, section Custom Field Parameters.

vtxyzzy – Thanks for your response.

The following might(?) help:

Looking at the code I’m using that produces the list of all the posts in a particular custom post type I wonder if there is a simple way of adding the custom field so that the query became something like
<?php $loop = new WP_Query( array( 'post_type' => 'glossary', 'meta_key'='A', 'posts_per_page' => 10 ) ); ?>

OR should it be something like
<?php $loop = new WP_Query( array( 'post_type' => 'glossary'&'meta_key'='A', 'posts_per_page' => 10 ) ); ?>

Or is the whole thing going to be more complicated because I have a different post type?

thanks for the referral to the page on queries, that’s helpful although it doesn’t show any examples of combining the custom post with a custom field to form a query. However, I’ll use it as a starting place to do some more experiments.
Thanks

I am guessing that your meta_key is not ‘A’, but something like ‘first-letter’. The meta_value is probably ‘A’ or ‘B’ or … .

If that is the case, the query can be written like this:

<?php $loop = new WP_Query( array( 'post_type' => 'glossary', 'meta_key'=> 'first-letter', 'meta_value' => 'A', 'posts_per_page' => 10 ) ); ?>

vtxyzzy

Thanks, that works – your help is very much appreciated.

One more question if I could:

Is there a way to pass a parameter into the query? The use for this would be avoid having to create 26 pages, one for each letter. The goal would be to have one page that is used for whatever letter was chosen.

Stealing from a technique used in Expression Engine I was wondering if its possible to put the letter in the link url so that the page displaying any letter would be created from the URL.
To illustrate the question:
Assume that I have a page that lists all the letters of the alphabet.
If I click on A the anchor tag associated with that letter is written in the code as
https://www.example.com/glossary/A
When you click on ‘A” then ‘A’ is passed to the template via the url and the list of entries for the letter A is created.

Is this possible? If so where would I look to understand how to accomplish?

Thanks

You can pass a query argument, but not quite in the way you showed. It should be added like this:

https://www.example.com/glossary/?letter=A

Then, in the code for the page, get the letter like this:

<?php $letter = $_GET['letter'];
$loop = new WP_Query( array( 'post_type' => 'glossary', 'meta_key'=> 'first-letter', 'meta_value' => $letter, 'posts_per_page' => 10 ) ); ?>

Of course, you should check to make sure that a letter was passed and do something as a default if not. Otherwise, your query may behave badly. ??

vtxyzzy

Works perfectly – Thank You!

Regarding default behavior, is that handled by putting conditionals around the code you gave me, something like:

<?php $letter = $_GET['letter'];
if ($letter=="") echo "No Entries Found!";
else
$loop = new WP_Query( array( 'post_type' => 'glossary', 'meta_key'=> 'first-letter', 'meta_value' => $letter, 'posts_per_page' => 10 ) ); ?>

You got it!

You could also just default to the letter ‘A’ if you wanted to.

vtxyzzy

Thanks for your help.

vtxyzzy

I thought your solution was better

You could also just default to the letter ‘A’ if you wanted to.

But I don’t know how to test it.

First the code I used to direct to the A page if there is nothing passed in the URL was
if ($letter=="") $letter==A;

Then with regard to testing I clicked on a link to produce a page that lists all posts whose title starts with C.
Next I edited to URL to remove only the letter, so that the end of the URL is:
glossary-list-by-first-letter?letter=

However, that produces the following error message

Fatal error: Call to a member function have_posts() on a non-object in /home/XXXXXXXXX…../twentyten/glossaryListLetter2v0.php on line 14

Not sure if my code is wrong or/and I need a better test method.

Any suggestions would be much appreciated.

Thanks.

I have tried what was written in this thread and it works to a degree.

However when I use:

<?php $letter = $_GET['letter'];
if ($letter=="") echo "No Entries Found!";
else
$loop = new WP_Query( array( 'post_type' => 'glossary', 'meta_key'=> 'first-letter', 'meta_value' => $letter, 'posts_per_page' => 10 ) ); ?>

I cannot seem to have the “No Entries Found” message, it just does not display anything but a blank page.

I have the following code in my template

<?php $letter = $_GET['letter'];
if ($letter=="") echo "No Entries Found!";
else
$loop = new WP_Query( array( 'post_type' => 'glossary', 'meta_key'=> 'first-letter', 'meta_value' => $letter, 'posts_per_page' => 10 ) ); ?>

<?php while ( $loop->have_posts() ) : $loop->the_post(); ?>
<div id="post-<?php the_ID(); ?>" class="jglossary">

<li><a class="fancybox" href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
</li>

</div>

<?php endwhile; // end of the loop. ?>

Am I doing something wrong?

why set the custom field when u can just use substrings?

why set the custom field when u can just use substrings?

Would you elucidate for the sake of the neophytes.

Thanks.