I have multiple sources, like this (say)
source src1{
...
}
source src2{
...
}
AND
index src1{
...
}
index src2{
...
}
src1 has sql query from one individual table and src2 has sql query based on another individual table.
Now, in the PHP script, how do I specify, which indexer to use?
Normally, in the PHP script, we write it this way
$ss = new SphinxClient;
$ss->setServer("localhost", 9312);
$ss->setMatchMode(SPH_MATCH_ANY);
Since, there is no mention about the indexer being used. It's useless to search both indexes (i.e., both tables). I want to search the index src2(say) i.e., data from the second table. So, how do I specify this in my php script, that sphinx should search only that particular indexer.
The Query call includes the index(s) to search
$res = $cl->Query($query,"src1");
For one index (per Barry Hunter)
$res = $cl->Query($query,"src1");
or
For multiple indexes for one query.
$res = $cl->Query($query,"src1 src2 src3 src4");
Related
Function render makes website 500% slow! Can anyone fix that please ?
Someone told me :
because it sends a database request on each iteration of the loop (it's not the only problem with this chunk of code but it's the most taxing one)
Yes I understand what that means. His way is:
you need to get all of the data before you start building the menu,
then you just insert the data instead of requesting more data on each
iteration
But i don't know how i must do it!
<?php
$menu_html='';
function render_menu($parent_id,$actmenuid)
{
$obj = new Database();
$con = $obj->dbconnectt();
global $menu_html;
$result=mysqli_query($con, "select * from tbl_menu where parent_id='$parent_id'");
if(mysqli_num_rows($result)==0) return;
if($parent_id==0){
$menu_html.='<ul class="topnav">';
}else{
$menu_html.='<ul>';
}
while($row=mysqli_fetch_array($result)) {
$childnum = $obj->recordcount("SELECT * FROM tbl_menu WHERE parent_id='".$row['id']."'");
if($childnum == 0){
$linkvalue='/category/'.$row['id'].'.html';
} else{
$linkvalue='#';
}
if($row['id']==$actmenuid && $actmenuid !=NULL){
$actv='class="active"';
}else{
$actv='';
}
$menu_html.='<li '.$actv.'>'.$row['title'].'';
render_menu($row['id'],$actmenuid);
$menu_html.='</li>';
}
$menu_html.='</ul>';return $menu_html;
}
if($isDsh==false){
echo render_menu(0,$actmenuid);
}
?>
Depending on how many records you have, try removing this query from inside the loop since it's running for every record on the first query.
$childnum = $obj->recordcount("SELECT * FROM tbl_menu WHERE parent_id='".$row['id']."'");
Change it a single query like this where it returns counts for each parent idea, and place it outside of the loop:
$parentcount = mysqli_query($con, ("SELECT parent_id, count(*) FROM tbl_menu GROUP BY parent_id");
There may be other issues, so please post the database structure and number of records that you're working with too.
Don't make recursive queries.
Having "more than 1000" rows is not too big. You can simply call everything from the table into php, then perform the recursive html build in php this will have a memory overhead, but far less processing overhead because you only ever make one trip to the db.
Alternatively (when your db table is prohibitively large), you should avoid gathering rows unnecessarily by adding a new column. The new column will store all "descendants" for the respective row when the row is INSERTed or update it when it is UPDATEd. Then you only need to reference this column when needing to call specific rows. In other words, do the recursive processing only once (when writing to the db) AND not when needing to display the data. This will, again, produce a finite result set in one query which can then be recursively traversed to build the desired output.
basically you need to do what #spudly has suggested.
But there is a small catch in his solution which depending on the number of the rows in yous tbl_menu table you may use a big chunk of memory to fetch all the records.
you can optimise it more with using his solution but changing the query to:
select
parent_tbl_menu.id,
count(child_tbl_menu.id) as cnt
from
tbl_menu as parent_tbl_menu
left join
tbl_menu as child_tbl_menu
on parent_tbl_menu.id = child_tbl_menu.parent_id
where
parent_tbl_menu.parent_id = ?
group by
parent_tbl_menu.id
This way you will only fetch the child records of a specific parent.
And please consider using prepared statements as your code has sql injection vulnerability.
Connect (from PHP to MySQL) only once for the entire web page.
Don't put a SELECT inside a loop if you can do all the work in a single SELECT, such as with a JOIN. (Exception: A "hierarchical" table needs the nested SELECT. Exception to the exception: MySQL 8.0 and MariaDB 10.2 can do it with a "recursive CTE".)
Don't fetch all the columns (SELECT *) when all you want it is a recordcount. Instead, SELECT COUNT(*) ... and use the number returned.
1000 of anything is probably excessive for a web page. Re-think the UI.
I have a strange situation.
Suppose I have a very simple function in php (I used Yii but the problem is general) which is called inside a transaction statement:
public function checkAndInsert($someKey)
{
$data = MyModel::model()->find(array('someKey'=>$someKey)); // search a record in the DB.If it does not exist, insert
if ( $data == null)
{
$data->someCol = 'newOne';
$data->save();
}
else
{
$data->someCol = 'test';
$data->save();
}
}
...
// $db is the instance variable used for operation on the DB
$db->transaction();
$this->checkAdnInsert();
$db->commit();
That said, if I run the script containing this function by staring many processes, I will have duplicate values in the DB. For example, if I have $someKey='pippo', and I run the script by starting 2 processes, I will have two (or more) records with column "someCol" = "newOne". This happens randomly, not always.
Is the code wrong? Should I put some constraint in DB in form of KEYs?
I also read this post about adding UNIQUE indexes to TokuDB which says that UNIQUE KEY "kills" write performance...
The approach you have is wrong. It's wrong because you delegate the authority for integrity/uniqueness check to PHP, but it's the database that's responsible for that.
In other words, you don't have to check whether something exists and then insert. That's bad because there's always some slight ping involved between PHP and MySQL and as you already saw - you can get false results for your checks.
If you need unique values for certain column or combination of columns, you add a UNIQUE constraint. After that you simply insert. If the record exists, insert fails and you can deal with it via Exception. Not only is it faster, it's also easier for you because your code can become a one-liner which is much easier to maintain or understand.
I have the following PHP script and am using the sphinx search API. I want to search for a custom keyword but only in the title column of the MySQL database.
$s = new SphinxClient;
$s->setServer("localhost", 9312);
$s->setMatchMode(SPH_MATCH_EXTENDED);
$s->SetLimits(0, 10000);
$result = $s->Query("#(title) apple");
Unfortunately this returns nothing but when i use the following script:
$s = new SphinxClient;
$s->setServer("localhost", 9312);
$s->setMatchMode(SPH_MATCH_EXTENDED);
$s->SetLimits(0, 10000);
$result = $s->Query("apple");
I obtain the results, the problem is that the script searches in all columns.
What am I doing wrong?
I should also mention that on localhost (using XAMPP) it is working fine like in the first example.
One thing I do notice, you dont explicitly note which index going to search - so the Query() searches ALL indexes.
Persumably then on one server you have an index that doesnt contain #title.
... for maximum compatiblity (so it doesnt matter waht other indexes add to the server, should probably search a specific index...
$s->Query("#(title) apple",'my_index');
I'm using sphinx to search our database. In this example, I'm querying two indexes; index1 and index2.
$res = $cl->Query( $query, "index1 index2" );
The results are good, but I can't distinguish the resulting IDs from index1 and index2 from within the code. Is there a way I can make all IDs coming from index1 look like: in1_1, in1_600, in1_x... So I can distinguish between them?
Just setup a attribute that identifies which index it came from, see
http://sphinxsearch.com/forum/view.html?id=5653
I'm trying to create a small search for my site. I've tried using full-text index search, but I could never get it to work. Here is what I've come up with:
if(isset($_GET['search'])) {
$search = str_replace('-', ' ', $_GET['search']);
$result = array();
$titles = mysql_query("SELECT title FROM Entries WHERE title LIKE '%$search%'");
while($row = mysql_fetch_assoc($titles)) {
$result[] = $row['title'];
}
$tags = mysql_query("SELECT title FROM Entries WHERE tags LIKE '%$search%'");
while($row = mysql_fetch_assoc($tags)) {
$result[] = $row['title'];
}
$text = mysql_query("SELECT title FROM Entries WHERE entry LIKE '%$search%'");
while($row = mysql_fetch_assoc($text)) {
$result[] = $row['title'];
}
$result = array_unique($result);
}
So basically, it searches through all the titles, body-text, and tags of all the entries in the DB. This works decently well, but I'm just wondering how efficient would it be? This would only be for a small blog, too. Either way I'm just wondering if this could be made any more efficient.
There's no way to make LIKE '%pattern%' queries efficient. Once you get a nontrivial amount of data, using those wildcard queries performs hundreds or thousands of times slower than using a fulltext indexing solution.
You should look at the presentation I did for MySQL University:
http://www.slideshare.net/billkarwin/practical-full-text-search-with-my-sql
Here's how to get it to work:
First make sure your table uses the MyISAM storage engine. MySQL FULLTEXT indexes support only MyISAM tables. (edit 11/1/2012: MySQL 5.6 is introducing a FULLTEXT index type for InnoDB tables.)
ALTER TABLE Entries ENGINE=MyISAM;
Create a fulltext index.
CREATE FULLTEXT INDEX searchindex ON Entries(title, tags, entry);
Search it!
$search = mysql_real_escape_string($search);
$titles = mysql_query("SELECT title FROM Entries
WHERE MATCH(title, tags, entry) AGAINST('$search')");
while($row = mysql_fetch_assoc($titles)) {
$result[] = $row['title'];
}
Note that the columns you name in the MATCH clause must be the same columns in the same order as those you declared in the fulltext index definition. Otherwise it won't work.
I've tried using full-text index search, but I could never get it to work... I'm just wondering if this could be made any more efficient.
This is exactly like saying, "I couldn't figure out how to use this chainsaw, so I decided to cut down this redwood tree with a pocketknife. How can I make that work as well as the chainsaw?"
Regarding your comment about searching for words that match more than 50% of the rows.
The MySQL manual says this:
Users who need to bypass the 50% limitation can use the boolean search mode; see Section 11.8.2, “Boolean Full-Text Searches”.
And this:
The 50% threshold for natural language
searches is determined by the
particular weighting scheme chosen. To
disable it, look for the following
line in storage/myisam/ftdefs.h:
#define GWS_IN_USE GWS_PROB
Change that line to this:
#define GWS_IN_USE GWS_FREQ
Then recompile MySQL. There is no need
to rebuild the indexes in this case.
Also, you might be searching for stopwords. These are words that are ignored by the fulltext search because they're too common. Words like "the" and so on. See http://dev.mysql.com/doc/refman/5.1/en/fulltext-stopwords.html
Using LIKE is NOT fulltext.
You need to use ... WHERE MATCH(column) AGAINST('the query') in order to access a fulltext search.
MySQL Full-text search works -- I would look into it and debug it rather than trying to do this. Doing 3 separate MySQL queries will not be anywhere near as efficient.
If you want to try to make that much efficient you could separate the LIKE statements in one query with OR between them.