Why doesn't my query work for retrieving substrings? - php

Question

Below is my query to show user comments. It works well:
enter
$query='SELECT
customers.cust_id,
customers.f_name,
customers.l_name,
user_comments.comment_txt,
clubs.name_club
from
customers
inner join
user_comments
on customers.cust_id = user_comments.cust_id
inner join
clubs
on user_comments.cust_id = clubs.cust_id
ORDER BY RAND() LIMIT 1,1
';
$result = mysql_query($query);
while($row = mysql_fetch_array($result)){
$nameclub =$row['name_club'];
$comment =$row['comment_txt'];
echo '<div><img src="images/arrow.gif"> Name : '.$nameclub.'</div>';
echo '<div>'.$comment.'</div><br>';
echo '<div>'.$row['f_name'].' '.$row['l_name'].'</div>';
}
echo '<p style="text-align: left"> Show all comments</ ></p> '; ?>
I now want to show just about 100 characters of a user comment. So I changed my query accordingly, but it does not work:
enter $query='SELECT
customers.cust_id,
customers.f_name,
customers.l_name,
user_comments.comment_txt.substr(comment_txt,1,100) as comment_txt,
clubs.name_club
from
customers
inner join
user_comments
on customers.cust_id = user_comments.cust_id
inner join
clubs
on user_comments.cust_id = clubs.cust_id
ORDER BY RAND() LIMIT 1,1
';
$result = mysql_query($query);
while($row = mysql_fetch_array($result)){
$nameclub =$row['name_club'];
$comment =$row['comment_txt'];
echo '<div><img src="images/arrow.gif"> Name : '.$nameclub.'</div>';
echo '<div>'.$comment.'</div><br>';
echo '<div>'.$row['f_name'].' '.$row['l_name'].'</div>';
}
echo '<p style="text-align: left"> Show all comments</ ></p> '; ?>
How can I fix my query to just get 100 characters of a comment?

Answer 1

You're using SUBSTR() incorrectly. Replace this:
user_comments.comment_txt.substr(comment_txt,1,100) as comment_txt,
With this:
SUBSTR(user_comments.comment_txt,1,100) as comment_txt,
Edit per comment: to add ... if the text continues past 100 characters, use
CONCAT(SUBSTR(user_comments.comment_txt,1,100), IF(LEN(user_comments.comment_txt) > 100, '...', '')) as comment_txt,

Answer 2

Try this
Replace this
user_comments.comment_txt.substr(comment_txt,1,100) as comment_txt,
To
SUBSTRING(user_comments.comment_txt,1,100) as comment_txt,
Mysql function_substring

Answer 3

Another solution is to use a php function that cuts a string into a number of words:
<?php
function cut_string($string_to_cut, $number_words, $append = "...") {
$string = array();
$string_return = "";
$return_string = "";
$string = explode(" ", $string_to_cut);
if(count($string) < $number_words) {
for($x=0; $x < count($string); $x++) {
$string_return .= $string[$x] . " ";
}
$return_string = substr($string_return, 0, -1);
}
else {
for($x=0; $x < $number_words; $x++) {
$string_return .= $string[$x] . " ";
}
$string = substr($string_return, 0, -1);
$return_string = $string . $append;
}
return($return_string);
}
?>
Note: This is word count based, not character count based.