firimar

This simple plugin allows you to import any type of data from large CSV files into your wordpress installation.
Plugin reads CSV file and performs import of its records one by one through AJAX requests, so there are no server timeout issues.
You only need to provide PHP function to perform import of CSV field values into post or taxonomy term or whatever you need.
Usage example:
For example, assume we want to import posts from such CSV file: 
 title,text,brand,image 
 “Check this”,”Samsung content”,Samsung,”https://upload.wikimedia.org/wikipedia/commons/thumb/2/24/Samsung_Logo.svg/2000px-Samsung_Logo.svg.png” 
 “Some news”,”News Here are some news”,Philips,”http://www.underconsideration.com/brandnew/archives/philips_2013_logo_detail.png”
Here we have post title, post content, custom field Brand and thumbnail image.
We can use this code in theme’s functions.php file to implement import function:
<pre><code>add_action('lcih_import_csv_row', 'lcih_import_csv_row');
function lcih_import_csv_row($row)
{
 $post_data = array(
 'post_type' => 'post',
 'post_status' => 'publish',
 'post_title' => $row['title'],
 'post_content' => $row['text']
 );
 $post_id = wp_insert_post($post_data);
 if (!$post_id)
 {
 echo "Error inserting post.";
 return;
 }

 update_post_meta($post_id, 'brand', $row['brand']);

 if ($row['image'])
 LargeCSVImportHandlerPlugin::download_post_thumbnail($post_id, $row['image']);

 echo "Created post ".$post_id;
}
</code></pre>
After that we can go to plugin admin page, select CSV file to upload and click “Start import” button. Import process will begin.

Large CSV Import Handler

After trying almost all major CSV plugins, this is the one that works perfectly for large files. I have a file of 35MB with 83000 posts and was unable to import them but this plugin did it with ease. No server time issues, simple to use. Recommended!

Awesome Work, Great Plugin

Provides ability to import any type of data from large CSV files into Wordpress

SATYA PRAKASH

Allows exporting post data into CSV format with filter options on the post dashboard screen.
<h3>Features</h3>
<ul>
<li>Export posts data.</li>
<li>Export posts data based on status.</li>
<li>Export posts data based on category.</li>
<li>Export posts data based on date.</li>
</ul>
<h3>Usage</h3>
After activating the plugin, you can export post data via the post dashboard screen.

Export Posts to CSV

Allows exporting post data into CSV format with filter options on the post dashboard screen.

Large CSV Import Handler vs Export Posts to CSV