searching mysql db for lat/long OR by name of item - php

I just wanted some advice really.
I am building a project where by I want to allow the users to search either by location or by a reference say restaurant name from the data that may exist in my db already.
Currently I have part implemented the location search where by the user can type in location say "nw5" and I then go get the approx lat/long and query my db with them coords. All good and works well.
I want to now add in a feature where the user can say "I know the restaurant name" - whacks it in and brings back the results accordingly.
I am sort of lost on how best to play this tbh.
Any insight would be appreciated.
Thanks
Raj

You're going to need some client-side magic for something like an autocomplete - jqueryui.com has a good one. Then you'll need a server-side ajax handler to run a query. Here's one I use, this is Doctrine but you could whip together a similar sql query:
function getLocByLabelChunk($chunkFromUser) {
$lower = strtolower($chunkFromUser);
$ls = str_split($lower);
$first = strtoupper($ls[0]);
$firstUp = $first;
for ($i=1; $i < count($ls); $i++) {
$firstUp .= $ls[$i];
}
$dql = "
SELECT l.locID as lID, l.label, l.label as value
FROM Entity\Location l
WHERE
l.label LIKE ?2
OR l.label LIKE ?3
OR l.label LIKE ?4
)
";
$q = $em->createQuery($dql);
$q->setParameter(2,"%" . $chunkFromUser. "%");
$q->setParameter(3,"%" . $lower . "%");
$q->setParameter(4,"%" . $firstUp . "%");
$locations = $q->getArrayResult();
return $locations;
}

Related

Efficient 2 dimensional array search in MySql

I am trying to design an application and part of it is to show users new articles in different categories after the last visit of the user to the webapp. To this I use MySql and have a table that keeps track of last visits and I can query the table to get a php array like below:
$array =[[user1,category1, datetime1],[user1,category2, datetime2],[user1,category3,datetime3]];
Where user is the user id and datetime is the visited datetime and category is the article category.
Having the setup above, I am trying to get new articles from the article table where the publish date is after user last visited to categories.
I can achieve this by multiple OR in a query like below, however it is not really a good and nice looking query, and probable not scalable. Is there any other way of doing this which is simpler and faster?
$multiwhere=[];
foreach($array as $a){
$multiwhere[]="select article_id from articles where category=".$a[1]." and publish_date>".$a[2];
}
And the final query would be like this:
"Select * from articles where article_id in (".implode(" or ".$multiwhere.")";
I deeply appreciate any suggestion to improve the query above.
Your query is almost correct, apart from the fact that you first retrieve all the article_id you want, and then use them to query for those articles. You can do that in one step, like so:
$multiwhere = [];
foreach ($array as $a) {
$multiwhere[] = "(category = " . $a[1] . " AND publish_date >= " . $a[2] .")";
}
$query = "SELECT * FROM articles";
if (count($multiwhere) > 0) {
$query = " WHERE " . implode(" OR ", $multiwhere);
}
One query will do.
I kept the way you use the $array, but it looks weird to me. Especially around publish_date. I cannot change that because I don't know the type of the field. And, of course, $array is quite a bad name. It tells you what the type of the variable is, not what it contains, as it should. A better name would be: $lastCategoryVisits, or something like that. Your loop should look something like this:
foreach ($lastCategoryVisits as $lastCategoryVisit) {
$category = $lastCategoryVisit["category"];
$lastVisit = $lastCategoryVisit["lastVisit"];
$QueryConditions[] = "(category = '$category' AND publish_date >= '$lastVisit')";
}
Don't be afraid to write out what your code actually does. It might be a bit longer, but now you can see what is going on. This will not slow down the execution of your code at all.
Finally, it would be better to always use prepared statements to prevent the possibility of SQL-injection. If you get into the habit of always doing this you don't have to use excuses like: "It is not important in this project.", "I'll to it later when the code works." or "The data for this query doesn't come from an user.".

Database search like google [duplicate]

This question already has answers here:
Google-like Search Engine in PHP/mySQL [closed]
(9 answers)
Closed 1 year ago.
I currently have a search option on my PHP+MYSQL website.
The MYSQL query is currently something like "SELECT pageurl WHERE name LIKE '%$query%'.
The reason I posted here is because I noticed that if the name of one of my products is "Blue Bike" and someone looks for "Bike Blue", no results are returned.
I am looking for a solution to this because I know that if I type on google same word, something appears.
I was thinking to create a PHP function to mix up all the words from the query if the query is having 4 or fewer words, generating around 24 queries.
Is there an easier solution to this?
Thanks for your time
As to not let this go without a working answer:
<?php
$search = 'this is my search';
$searchSplit = explode(' ', $search);
$searchQueryItems = array();
foreach ($searchSplit as $searchTerm) {
/*
* NOTE: Check out the DB connections escaping part
* below for the one you should use.
*/
$searchQueryItems[] = "name LIKE '%" . mysqli_real_escape_string($searchTerm) . "%'";
}
$query = 'SELECT pageurl FROM names' . (!empty($searchQueryItems) ? ' WHERE ' . implode(' AND ', $searchQueryItems) : '');
?>
DB connections escaping
mysqli_:
Keep using mysqli_real_escape_string or use $mysqli->real_escape_string($searchTerm).
mysql_:
if you use mysql_ you should use mysql_real_escape_string($searchTerm) (and think about changing as it's deprecated).
PDO:
If you use PDO, you should use trim($pdo->quote($searchTerm), "'").
use full text search instead of like
full text search based on indexed text and is very faster and beter than using like.
see this article for more information about full text search
What you are looking for is fulltext search.
Try Sphinx, it is very fast and integrates well with MySQL.
Sphinx website
I wrote a function that approaches Google's operation taking into account the double quotes for the elements to search as a whole block. It does NOT take into account the - or * instructions.
table: MySQL table to consider
cols: array of column to parse
searchParams: search to process. For example: red mustang "Florida 90210"
function naturalQueryConstructor($table, $cols, $searchParams) {
// Basic processing and controls
$searchParams = strip_tags($searchParams);
if( (!$table) or (!is_array($cols)) or (!$searchParams) ) {
return NULL;
}
// Start query
$query = "SELECT * FROM $table WHERE ";
// Explode search criteria taking into account the double quotes
$searchParams = str_getcsv($searchParams, ' ');
// Query writing
foreach($searchParams as $param) {
if(strpos($param, ' ') or (strlen($param)<4)) {
// Elements with space were between double quotes and must be processed with LIKE.
// Also for the elements with less than 4 characters. (red and "Florida 90210")
$query .= "(";
// Add each column
foreach($cols as $col) {
if($col) {
$query .= $col." LIKE '%".$param."%' OR ";
}
}
// Remove last ' OR ' sequence
$query = substr($query, 0, strlen($query)-4);
// Following criteria will added with an AND
$query .= ") AND ";
} else {
// Other criteria processed with MATCH AGAINST (mustang)
$query .= "(MATCH (";
foreach($cols as $col) {
if($col) {
$query .= $col.",";
}
}
// Remove the last ,
$query = substr($query, 0, strlen($query)-1);
// Following criteria will added with an AND
$query .= ") AGAINST ('".$param."' IN NATURAL LANGUAGE MODE)) AND ";
}
}
// Remove last ' AND ' sequence
$query = substr($query, 0, strlen($query)-5);
return $query;
}
Thanks to the stackoverflow community where I found parts of this function!
To have a google like search you'd need many database and index nodes, crazy algorithms.. now you come up with a SELECT LIKE ... lol :D
MySQL is slow in searching, you'd need fulltext and index set properly (MyISAM or Aria Engine). Combinations or different entities to search for are almost not implementable properly AND fast.
I'd suggest to setup an Elasticsearch server which is based on Apache's Lucene.
This searchs very fast and is easy to maintain. And you would not have to care about SQL injection and can still use the mysql server fast.
Elasticsearch (or other Lucene based search engines like SolR) can easily be installed on any server because they are written in Java.
Good documentation:
http://www.elasticsearch.org/guide/en/elasticsearch/client/php-api/current/
I would do an explode first:
$queryArray = explode(" ", $query);
and then generate the SQL query something like:
for ($i=0; $i< count($queryArray); $i++) {
$filter += " LIKE '%" + $queryArray[$i] + "%' AND" ;
}
$filter = rtrim ($filter, " AND");
$sql = "SELECT pageurl FROM ... WHERE name " + $filter
(note: haven't tested/run this code)

Splitting a string of values like 1030:0,1031:1,1032:2 and storing data in database

I have a bunch of photos on a page and using jQuery UI's Sortable plugin, to allow for them to be reordered.
When my sortable function fires, it writes a new order sequence:
1030:0,1031:1,1032:2,1040:3,1033:4
Each item of the comma delimited string, consists of the photo ID and the order position, separated by a colon. When the user has completely finished their reordering, I'm posting this order sequence to a PHP page via AJAX, to store the changes in the database. Here's where I get into trouble.
I have no problem getting my script to work, but I'm pretty sure it's the incorrect way to achieve what I want, and will suffer hugely in performance and resources - I'm hoping somebody could advise me as to what would be the best approach.
This is my PHP script that deals with the sequence:
if ($sorted_order) {
$exploded_order = explode(',',$sorted_order);
foreach ($exploded_order as $order_part) {
$exploded_part = explode(':',$order_part);
$part_count = 0;
foreach ($exploded_part as $part) {
$part_count++;
if ($part_count == 1) {
$photo_id = $part;
} elseif ($part_count == 2) {
$order = $part;
}
$SQL = "UPDATE article_photos ";
$SQL .= "SET order_pos = :order_pos ";
$SQL .= "WHERE photo_id = :photo_id;";
... rest of PDO stuff ...
}
}
}
My concerns arise from the nested foreach functions and also running so many database updates. If a given sequence contained 150 items, would this script cry for help? If it will, how could I improve it?
** This is for an admin page, so it won't be heavily abused **
you can use one update, with some cleaver code like so:
create the array $data['order'] in the loop then:
$q = "UPDATE article_photos SET order_pos = (CASE photo_id ";
foreach($data['order'] as $sort => $id){
$q .= " WHEN {$id} THEN {$sort}";
}
$q .= " END ) WHERE photo_id IN (".implode(",",$data['order']).")";
a little clearer perhaps
UPDATE article_photos SET order_pos = (CASE photo_id
WHEN id = 1 THEN 999
WHEN id = 2 THEN 1000
WHEN id = 3 THEN 1001
END)
WHERE photo_id IN (1,2,3)
i use this approach for exactly what your doing, updating sort orders
No need for the second foreach: you know it's going to be two parts if your data passes validation (I'm assuming you validated this. If not: you should =) so just do:
if (count($exploded_part) == 2) {
$id = $exploded_part[0];
$seq = $exploded_part[1];
/* rest of code */
} else {
/* error - data does not conform despite validation */
}
As for update hammering: do your DB updates in a transaction. Your db will queue the ops, but not commit them to the main DB until you commit the transaction, at which point it'll happily do the update "for real" at lightning speed.
I suggest making your script even simplier and changing names of the variables, so the code would be way more readable.
$parts = explode(',',$sorted_order);
foreach ($parts as $part) {
list($id, $position) = explode(':',$order_part);
//Now you can work with $id and $position ;
}
More info about list: http://php.net/manual/en/function.list.php
Also, about performance and your data structure:
The way you store your data is not perfect. But that way you will not suffer any performance issues, that way you need to send less data, less overhead overall.
However the drawback of your data structure is that most probably you will be unable to establish relationships between tables and make joins or alter table structure in a correct way.

Include within a while loop

I'm sure my inability to solve this problem steams from a lack of knowledge of some aspect of php but I've been trying to solve it for a month now with no luck. Here is a simplified version of the problem.
In my database I have a members table, a childrens table (the children of each member), and a friend requests table (this contains the friend requests children send to each other).
What I'm attempting to do is display the children of a particular parent using the following while loop....
$query = "SELECT * From children " . <br>
"WHERE parent_member_id = $member_id"; <br>
$result = mysql_query($query) <br>
or die(mysql_error());<br>
$num_children = mysql_num_rows($result);<br>
echo $num_children;<br>
while($row = mysql_fetch_array($result)){<br>
$first_name = $row['first_name'];<br>
$child_id = $row['child_id'];<br>
<div>echo $first_name<br>
}
This while loop works perfectly and displays something like this...
1) Kenneth
2) Larry
What I'm attempting to do though is also display the number of friend requests each child has next to their name...like this
Kenneth (2)
Larry (5)
To do this I attempted the following modification to my original while loop...
$query = "SELECT * From children " .<br>
"WHERE parent_member_id = $member_id";<br>
$result = mysql_query($query) <br>
or die(mysql_error());<br>
$num_movies = mysql_num_rows($result);<br>
echo $num_movies;<br>
while($row = mysql_fetch_array($result)){<br>
$first_name = $row['first_name'];<br>
$child_id = $row['child_id'];<br>
echo $first_name; include('counting_friend_requests.php') ;
}
In this version the included script looks like this...
$query = "SELECT <br>children.age,children.child_id,children.functioning_level,children.gender,children.parent_member_id,children.photo, children.first_name,friend_requests.request_id " .
"FROM children, friend_requests " .
"WHERE children.child_id = friend_requests.friend_two " .
"AND friend_requests.friend_one = $child_id"; <br>
$result = mysql_query($query)<br>
or die(mysql_error());<br>
$count = mysql_num_rows($result);<br>
if ($count==0)<br>
{<br>
$color = "";<br>
}<br>
else<br>
{<br>
$color = "red";<br>
}<br>
echo span style='color:$color' ;<br>
echo $count;<br>
echo /span;<br>
Again this while loop begins to work but the included file causes the loop to stop after the first record is returned and produces the following output...
Kenneth (2)
So my question is, is there a way to display my desired results without interrupting
the while loop? I'd appreciate it if anyone could even point me in the right direction!!
Avoid performing sub queries in code like the plague, because it will drag your database engine down as the number of records increase; think <members> + 1 queries.
You can create the query like so to directly get the result you need (untested):
SELECT child_id, first_name, COUNT(friend_two) AS nr_of_requests
From children
LEFT JOIN friend_requests ON friend_one = child_id OR friend_two = child_id
WHERE parent_member_id = $member_id
GROUP BY child_id, first_name;
It joins the children table records with friend_requests based on either friend column; it then groups based on the child_id to make the count() work.
You don't need to include the php file everytime you loop. Try creating a Person class that has a method getFriendRequestCount(). This method can all the database. This also means you can create methods like getGriendRequests() which could return an array of the friend requests, names etc. Then you could use count($myPerson->getFriendRequests()) to get the number. Thousands of options!
A great place to start, http://php.net/manual/en/language.oop5.php
Another example of a simple class, http://edrackham.com/php/php-class-tutorial/
Eg.
include ('class.Person.php');
while(loop through members)
$p = new Person(member_id)
echo $p->getName()
echo $p->getFriendRequestCount()
foreach($p->getFriendRequests as $fr)
echo $fr['Name']
In your Person class you want to have a constructor that grabs the member from the database and saves it into a private variable. That variable can then be accessed by your functions to proform SQL queries on that member.
Just to clarify whats happening here.
"include" processing is done when the script is parsed. Essentially its just copying the text from the include file into the current file. After this is done the logic is then parsed.
You should keep any include statements separate from you main logic. In most cases the "include"d code will contain definitions for one or more functions. You can then call these functions from the main body of your program at the appropriate place.

Specialized Search Query Refinement for Auto-Complete function

I am doing a query for an autocomplete function on a mysql table that has many instances of similar titles, generally things like different years, such as '2010 Chevrolet Lumina' or 'Chevrolet Lumina 2009', etc.
The query I am currently using is:
$result = mysql_query("SELECT * FROM products WHERE MATCH (name) AGAINST ('$mystring') LIMIT 10", $db);
The $mystring variable gets built as folows:
$queryString = addslashes($_REQUEST['queryString']);
if(strlen($queryString) > 0) {
$array = explode(' ', $queryString);
foreach($array as $var){
$ctr++;
if($ctr == '1'){
$mystring = '"' . $var . '"';
}
else {
$mystring .= ' "' . $var . '"';
}
}
}
What I need to be able to do is somehow group things so only one version of a very similar actually shows in the autosuggest dropdown, leaving room for other products with chevrolet in them as well. Currently it is showing all 10 spots filled with the same product with different years, options, etc.
This one should give some of you brainiacs a good workout :)
I think the best way to do this would be to create a new field on the products table, something like classification. All the models would be entered with the same classification (e.g. "Chevrolet"). You could then still MATCH AGAINST name, but GROUP BY classification. Assuming you are using MySQL you can cheat a little and get away with selecting values and matching against values that you are not grouping by. Technically in SQL this gives undefined results and many SQL engines will not even let you try to do this, but MySQL lets you do it -- and it returns a more-or-less random sample that matches. So, for example, if you did the above query, grouped by classification, only one model (picked pretty much at random) will show up in the auto-completer.

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