Mysql search string - php

Question

I have a search box that will search for a keyword in the field : description
then return results. its done in mysql and php.
the description can go from 10 to 600 characters long. I would like to return only a part of result.
for example :
I am searching for the keyword= John
instead of displaying the whole field description as the result I want to see the sentence where the keyword is found only: ... Hello my name is john and I ...
not the whole paragraph.
I can use sql or php whichever one is better. I tried substring but failed implementing it any example would be great.
SELECT SUBSTR(description,2,100)
FROM screenplays
WHERE lower(description) like '% $search_word_fix %'

Answer 1

I thought by query, it will hamper performance. Because of string calculations. So I have done this by php substr function logic.
SELECT description
FROM screenplays
WHERE lower(description) like '% $search_word_fix %'
//$description will have longer string.
//$short_string will have shorter string.
$short_string=get_less_string($description,'john',20);
function get_less_string($string,$key,$num){
$desc=explode($key,$string);
$left='...'.substr($desc[0], strlen($desc[0])-$num,$num);
$right=substr($desc[1],0,$num).'...';
$final_string=$left.$key.$right;
return $final_string;
}

Answer 2

if you want to use php.. I had written a function few months back. It searches for keywords in a text and returns a string with 'bold' keywords. Hope this helps.
$str = 'I have a search box that will search for a keyword in the field : description then return results. its done in mysql and php. the description can go from 10 to 600 characters long. I would like to return only a part of result. for example : I am searching for the keyword= John instead of displaying the whole field description as the result I want to see the sentence where the keyword is found only: ... Hello my name is john and I ... not the whole paragraph.
I can use sql or php whichever one is better. I tried substring but failed implementing it any example would be great.';
$search = array();
$search[] = "example";
echo descriptionSearch($str,$search);
function descriptionSearch($desc,$words,$max_number_words = 30)
{
$descs = explode(" ",$desc);
$positions = array();
$i = 0;
foreach($words as $w)
{
$j = 0;
foreach($descs as $d)
{
$w = strtolower(trim($w));
$d = strtolower(trim($d));
if(strpos($d,$w) !== false)
{
$positions[] = $j;
$descs[$j] = str_replace($w,"<span style='font-weight: bold;'>".$d."</span>",$d);
}
$j++;
}
$i++;
}
$max = 0;
if(sizeof($positions) > 0)
{
foreach($positions as $j)
{
if($max < 4)
{
$i = $j -5;
if($i < 0)
{
$i = 0;
}
while($i < ($j+10))
{
$toreturn .= $descs[$i]." ";
$i++;
}
$toreturn .= " ...";
$max++;
}
}
}
else
{
for($i=0; $i < $max_number_words; $i++)
{
$toreturn .= $descs[$i]." ";
}
}
return $toreturn;
}

Answer 3

You CAN do it either way, and both will be about as efficient. PHP is probably a better more flexible solution, but just for kicks I tried to do it in MySQL, to see how it would work
SELECT SUBSTR(
description,
if(INSTR(description, '$search_word_fix') - 10 < 0,
0,
(INSTR(description, '$search_word_fix') - 10)),
if(
INSTR(description, '$search_word_fix') + 10 >
length(description),
length(description),
NSTR(description, '$search_word_fix') + 10))
FROM screenplays
WHERE lower(description) LIKE '% $search_word_fix %'

Answer 4

Modified answer, This can search better. In this example. I am searching for 'for example' or 'john'
$str = 'I have a search box that will search for a keyword in the field : description then return results. its done in mysql and php. the description can go from 10 to 600 characters long. I would like to return only a part of result. for example : I am searching for the keyword= John instead of displaying the whole field description as the result I want to see the sentence where the keyword is found only: ... Hello my name is john and I ... not the whole paragraph.
I can use sql or php whichever one is better. I tried substring but failed implementing it any example would be great.';
$search = array();
$search[] = "for example";
$search[] = "john";
echo descriptionSearch($str,$search);
function descriptionSearch($desc,$words,$max_number_words = 30)
{
$positions = array();
$i = 0;
foreach($words as $w)
{
$w = strtolower(trim($w));
$d = strtolower(trim($d));
if(strpos($desc,$w) !== false)
{
$positions[] = strpos($desc,$w);
$desc = str_replace($w,"<span style='font-weight: bold;'>".substr($desc,strpos($desc,$w),strlen($w))."</span>",$desc);
}
$i++;
}
$max = 0;
if(sizeof($positions) > 0)
{
foreach($positions as $j)
{
if($max < 4)
{
$i = $j -16;
if($i < 0)
{
$i = 0;
}
$toreturn .= substr($desc,$i,80);
$toreturn .= " ...";
$max++;
}
}
}
else
{
$descs = explode(" ",$desc);
for($i=0; $i < $max_number_words; $i++)
{
$toreturn .= $descs[$i]." ";
}
}
return $toreturn;
}