这里需要一些php / mysql手持：在导入之前是否存在wordpress帖子

Question

I have a wordpress install and am trying to see if a post already exists before I import it from a CSV

If I use phpmyadmin, the following search is 100% true and yields 2 accurate results:

SELECT * FROM `wp_posts` WHERE `post_title` LIKE 'the quick brown fox'

Then when I Select the "create php" link, I get this:

$sql = "SELECT * FROM `wp_posts` WHERE `post_title` LIKE \'the quick brown fox\'";

I then create import.php and save it with this:

<?php
include '/path/to/wp-blog-header.php';
$sql = "SELECT * FROM `wp_posts` WHERE `post_title` LIKE \'the quick brown fox\'";
$existingPost = mysql_query($sql);
if (!$existingPost) {
    echo "post does not exist. Running insertFromCSV.php";
    include "insertFromCSV.php"; //defined elsewhere and 100% working
    }
else {
    echo "you already have this in your database";
    }
?>

The issue is that when I run import.php, the result is "post does not exist. Running insertFromCSV.php" which is NOT true. The post title DOES in fact exist.

Where am I going wrong here? Where is my human error? :)

I appreciate any thoughts on this and thanks in advance...

Answer 1

From the PHP site:

For SELECT, SHOW, DESCRIBE, EXPLAIN and other statements returning resultset, mysql_query() returns a resource on success, or FALSE on error.

So the first problem is that mysql_query doesn't do what you want. It returns a resource, which you can use to fetch the result. In your case it doesn't return a resource, thus there is some error.

To see if the amount of posts returned from your query, you need to use mysql_num_rows:

 $res = mysql_query(..);
 $rowcount = mysql_num_rows($res);

Further more:

$sql = "SELECT * FROM `wp_posts` WHERE `post_title` LIKE \'the quick brown fox\'";

Should be:

$sql = "SELECT * FROM `wp_posts` WHERE `post_title` LIKE 'the quick brown fox'";

And if you want the actual posts:

 $res = mysql_query(...);
 $posts = mysql_fetch_array($res);

And better use PDO or some other abstraction layer instead of the mysql_* functions. They have a lot of handy features.