Should be a nice easy one today but I can't find the answer anywhere.
I have a multidimensional array. It stores partid and quantity.
$pCombined[] = array ( $newName[$b], $newQty[$b] );
I want to use PHP join as suggested here: Passing an array to a query using a WHERE clause
I need to get more data from mySQL about the parts so I need the list of ids joined up as I don't like the idea of running one SQL query for each row.
I tried to use:
$ids = join(',', $pCombined);
That just gives array, array, array....e.t.c.
I tried a few obvious combinations of square brackets. What I guess I want is...
$ids = join(',', $pCombined[*][0]); (where * is all)
I think I might also be overcomplicating the whole thing and I could use foreach or a for loop and join manually I guess. Its not quite a basic shopping cart but the principals are similar. Any ideas how I can do this or perhaps push me in a different direction. Thanks.
to combine array elements can use the following
$elemens = array("one","two","there","four")
$exit = implode(',',$elements);
print_r($exit);//one,two,...
I hope you serve
Related
I have array like this:
$array = array("AAA,http://aaa.com,bbb,http://bbb.com,ccc,http://ccc.com");
How can I take this array and insert into database like this:
No name url
1. AAA. Http://aaa.com
2. BBB. Http://bbb.com
3. CCC. Http://ccc.com
Using PHP and MySQL.
Thank you.
Assembling one INSERT statement with multiple rows is much faster in MySQL than one INSERT statement per row.
That said, it sounds like you might be running into string-handling problems in PHP, which is really an algorithm problem, not a language one. Basically, when working with large strings, you want to minimize unnecessary copying. Primarily, this means you want to avoid concatenation. The fastest and most memory efficient way to build a large string, such as for inserting hundreds of rows at one, is to take advantage of the implode() function and array assignment.
$sql = array();
foreach( $data as $row ) {
$sql[] = '("'.mysql_real_escape_string($row['text']).'", '.$row['category_id'].')';
}
mysql_query('INSERT INTO table (text, category) VALUES '.implode(',', $sql));
The advantage of this approach is that you don't copy and re-copy the SQL statement you've so far assembled with each concatenation; instead, PHP does this once in the implode() statement. This is a big win.
If you have lots of columns to put together, and one or more are very long, you could also build an inner loop to do the same thing and use implode() to assign the values clause to the outer array.
please try and good luck
I'm using PHP but that's not important. I have a variable that contains a standard array of positive int IDs. And I want to do a SELECT query with this array against a MySQL table to find out what IDs are not already existing in the data table. My first thought was to use IN() but then I realized that doing it that way I can only get a list of IDs that do exist not ones that don't. Of course with a list of IDs that do exist, I could compile it into a second array and then use array_diff() but I can't help wondering if there's another way to do it.
I decided to use unset()
SELECT QUERY
where (row) {
unset(id)
}
I'm not sure that I have the terminology correct but basically I have a website where members can subscribe to topics that they like and their details go into a 'favorites' table. Then when there is an update made to that topic I want each member to be sent a notification.
What I have so far is:
$update_topic_sql = "UPDATE topics SET ...My Code Here...";
$update_topic_res = mysqli_query($con, $update_topic_sql)or die(mysqli_error());
$get_favs_sql = "SELECT member FROM favourites WHERE topic = '$topic'";
$get_favs_res = mysqli_query($con, $get_favs_sql);
//Here I Need to update the Members selected above and enter them into a notes table
$insert_note_sql = "INSERT INTO notes ....";
Does anyone know how this can be achieved?
Ok, so we've got our result set of users. Now, I'm going to assume from the nature of the question that you may be a bit of a newcomer to either PHP, SQL(MySQL in this case), web development, or all of the above.
Your question part 1:
I have no idea how to create an array
This is easier than what you may think, and if you've already tried this then I apologize, I don't want to insult your intelligence. :)
Getting an array from a mysqli query is just a matter of a function call and a loop. When you ran your select query and saved the return value to a variable, you stored a mysqli result set. The mysqli library supports both procedural and object oriented styles, so since you're using the procedural method, so will I.
You've got your result set
$get_favs_res = mysqli_query($con, $get_favs_sql);
Now we need an array! At this point we need to think about exactly what our array should be of, and what we need to do with the contents of the request. You've stated that you want to make an array out of the results of the SELECT query
For the purposes of example, I'm going to assume that the "member" field you've returned is an ID of some sort, and therefore a numeric type, probably of type integer. I also don't know what your tables look like, so I'll be making some assumptions there too.
Method 1
//perform the operations needed on a per row basis
while($row = mysqli_fetch_assoc($get_favs_res)){
echo $row['member'];
}
Method 2
//instead of having to do all operations inside the loop, just make one big array out of the result set
$memberArr = array();
while($row = mysqli_fetch_assoc($get_favs_res)){
$memberArr[] = $row;
}
So what did we do there? Let's start from the beginning to give you an idea of how the array is actually being generated. First, the conditional in the while loop. We're setting a variable as the loop condition? Yup! And why is that? Because when PHP (and a lot of other languages) sets that variable, the conditional will check against the value of the variable for true or false.
Ok, so how does it get set to false? Remember, any non boolean false, non null, non 0 (assuming no type checking) resolves to true when it's assigned to something (again, no type checking).
The function returns one row at a time in the format of an associative array (hence the _assoc suffix). The keys to that associative array are simply the names of the columns from the row. So, in your case, there will be one value in the row array with the name "member". Each time mysqli_fetch_assoc() is called with your result set, a pointer is pointed to the next result in the set (it's an ordered set) and the process repeats itself. You essentially get a new array each time the loop iterates, and the pointer goes to the next result too. Eventually, the pointer will hit the end of the result set, in which case the function will return a NULL. Once the conditional picks up on that NULL, it'll exit.
In the second example, we're doing the exact same thing as the first. Grabbing an associative array for each row, but we're doing something a little differently. We're constructing a two dimensional array, or nested array, of rows. In this way, we can create a numerically indexed array of associative arrays. What have we done? Stored all the rows in one big array! So doing things like
$memberArr[0]['member'];//will return the id of the first member returned
$memberArr[1]['member'];//will return the id of the second member returned
$lastIndex = sizeof($memberArr-1);
$memberArr[$lastIndex]['member'];//will return the id of the last member returned.
Nifty!!!
That's all it takes to make your array. If you choose either method and do a print_r($row) (method 1) or print_r($memberArr) (method 2) you'll see what I'm talking about.
You question part 2:
Here I Need to update the Members selected above and enter them into a notes table
This is where things can get kind of murky and crazy. If you followed method 1 above, you'd pretty much have to call
mysqli_query("INSERT INTO notes VALUES($row['member']);
for each iteration of the loop. That'll work, but if you've got 10000 members, that's 10000 inserts into your table, kinda crap if you ask me!
If you follow method two above, you have an advantage. You have a useful data structure (that two dim array) that you can then further process to get better performance and make fewer queries. However, even from that point you've got some challenges, even with our new processing friendly array.
The first thing you can do, and this is fine for a small set of users, is use a multi-insert. This just involves some simple string building (which in and of itself can pose some issues, so don't rely on this all the time) We're gonna build a SQL query string to insert everything using our results. A multi insert query in MySQL is just like a normal INSERT except for one different: INSERT INTO notes VALUES (1),(2),(x)
Basically, for each row you are inserted, you separate the value set, that set delineated by (), with a comma.
$query = 'INSERT INTO notes VALUES ';
//now we need to iterate over our array. You have your choice of loops, but since it's numerically indexed, just go with a simple for loop
$numMembers = sizeof($memberArr);
for($i = 0; $i < $numMembers; $i++){
if($i > 0){
$query .= ",({$membersArr[$i]['member']})";//all but the first row need a comma
}
else {
$query .= "({$membersArr[$i]['member']})";//first row does not need a comma
}
}
mysqli_query($query);//add all the rows.
Doesn't matter how many rows you need to add, this will add them. However, this is still going to be a costly way to do things, and if you think your sets are going to be huge, don't use it. You're going to end up with a huge string, TONS of string concats, and an enormous query to run.
However, given the above, you can do what you're trying to do.
NOTE: These are grossly simplified ways of doing things, but I do it this way because I want you to get the fundamentals down before trying something that's going to be way more advanced. Someone is probably going to comment on this answer without reading this note telling me I don't know what I'm doing for going about this so dumbly. Remember, these are just the basics, and in no way reflect industrial strength techniques.
If you're curious about other ways of generating arrays from a mysqli result set:
The one I used above
An even easier way to make your big array but I wanted to show you the basic way of doing things before giving you the shortcuts. This is also one of those functions you shouldn't use much anyway.
Single row as associative(as bove), numeric, or both.
Some folks recommend using loadfiles for SQL as they are faster than inserts (meaning you would dump out your data to a file, and use a load query instead of running inserts)
Another method you can use with MySQL is as mentioned above by using INSERT ... SELECT
But that's a bit more of an advanced topic, since it's not the kind of query you'd see someone making a lot. Feel free to read the docs and give it a try!
I hope this at least begins to solve your problem. If I didn't cover something, something didn't make sense, or I didn't your question fully, please drop me a line and I'll do whatever I can to fix it for you.
Not sure if this is possible but im trying to run array_unique over a collection of items i have, to remove duplicates. Although i cannot get it working.
my controller logic:
// init models
$jobs = Job::search();
$countries = $jobs->get()->map(function( $job ) {
return $job->country;
});
$countries = array_unique( $countries->toArray() );
although this gets a "Array to string conversion" error
You could try the Unique method of the Collection class:
$countries = $countries->unique();
The Collection class has several wonderful methods. You could read about this in the Laravel API documentation.
I agree that sometimes it is more efficient to "query" on an existing Collection in memory (in stead of doing another query on the database using the Querybuilder class), like for example you first want to count and then filter. In .NET LINQ you can query almost equally on an IEnumerable (in-memory collection) as on a database, something I really enjoy.
I had similar issue and although time have passed since it may be useful to someone today.
The Problem I had was that when I called unique method on collection of items it didn't worked, that is probably the reason the first answer got accepted. So if you have models and you want to remove duplicates based on a specific field you can pass parameter to your unique method, in this case it would be:
$countries->unique('code');
that way you'll only have countries with unique codes. You may notice that only the first value stays, so if you develop a shopping cart application and want for some reason merge carts and only want to have recent items you can just reverse the collection and call unique and reverse it back:
$countries->reverse()->unique('code')->reverse(); // it doesn't really make sense in this example though
it is probably not the best option and it is better to do filtering on the database side but it is nice to have options.
You can have unique values in your DB results using distinct or group by in your select clause. But, if you really need to have unique values over an array of object you can do the following:
$uniques = array();
foreach ($countries as $c) {
$uniques[$c->code] = $c; // Get unique country by code.
}
dd($uniques);
You could try the filter method on eloquent collections if that's exactly what you want to do
http://laravel.com/docs/eloquent#collections
I'm storing a list of items in a serialized array within a field in my database (I'm using PHP/MySQL).
I want to have a query that will select all the records that contain a specific one of these items that is in the array.
Something like this:
select * from table WHERE (an item in my array) = '$n'
Hopefully that makes sense.
Any ideas would be greatly appreciated.
Thanks
As GWW says in the comments, if you need to query things this way, you really ought to be considering storing this data as something other than a big-ole-string (which is what your serialized array is).
If that's not possible (or you're just lazy), you can use the fact that the serialized array is just a big-ole-string, and figure out a LIKE clause to find matching records. The way PHP serializes data is pretty easy to figure out (hint: those numbers indicate lengths of things).
Now, if your serialized array is fairly complex, this will break down fast. But if it's a flat array, you should be able to do it.
Of course, you'll be using LIKE '%...%', so you'll get no help from any indicies, and performance will be very poor.
Which is why folks are suggesting you store that data in some normalized fashion, if you need to query "inside" it.
If you have control of the data model, stuffing serialized data in the database will bite you in the long run just about always. However, oftentimes one does not have control over the data model, for example when working with certain open source content management systems. Drupal sticks a lot of serialized data in dumpster columns in lieu of a proper model. For example, ubercart has a 'data' column for all of its orders. Contributed modules need to attach data to the main order entity, so out of convenience they tack it onto the serialized blob. As a third party to this, I still need a way to get at some of the data stuffed in there to answer some questions.
a:4:{s:7:"cc_data";s:112:"6"CrIPY2IsMS1?blpMkwRj[XwCosb]gl<Dw_L(,Tq[xE)~(!$C"9Wn]bKYlAnS{[Kv[&Cq$xN-Jkr1qq<z](td]ve+{Xi!G0x:.O-"=yy*2KP0#z";s:7:"cc_txns";a:1:{s:10:"references";a:1:{i:0;a:2:{s:4:"card";s:4:"3092";s:7:"created";i:1296325512;}}}s:13:"recurring_fee";b:1;s:12:"old_order_id";s:2:"25";}
see that 'old_order_id'? thats the key I need to find out where this recurring order came from, but since not everybody uses the recurring orders module, there isnt a proper place to store it in the database, so the module developer opted to stuff it in that dumpster table.
My solution is to use a few targeted SUBSTRING_INDEX's to chisel off insignificant data until I've sculpted the resultant string into the data gemstone of my desires.
Then I tack on a HAVING clause to find all that match, like so:
SELECT uo.*,
SUBSTRING_INDEX(
SUBSTRING_INDEX(
SUBSTRING_INDEX( uo.data, 'old_order_id' , -1 ),
'";}', 1),
'"',-1)
AS `old order id`
FROM `uc_orders AS `uo`
HAVING `old order id` = 25
The innermost SUBSTRING_INDEX gives me everything past the old_order_id, and the outer two clean up the remainder.
This complicated hackery is not something you want in code that runs more than once, more of a tool to get the data out of a table without having to resort to writing a php script.
Note that this could be simplified to merely
SELECT uo.*,
SUBSTRING_INDEX(
SUBSTRING_INDEX( uo.data, '";}' , 1 ),
'"',-1)
AS `old order id`
FROM `uc_orders` AS `uo`
HAVING `old order id` = 25
but that would only work in this specific case (the value I want is at the end of the data blob)
So you mean to use MySQL to search in a PHP array that has been serialized with the serialize command and stored in a database field? My first reaction would be: OMG. My second reaction would be: why? The sensible thing to do is either:
Retrieve the array into PHP, unserialize it and search in it
Forget about storing the data in MySQL as serialized and store it as a regular table and index it for fast search
I would choose the second option, but I don't know your context.
Of course, if you'd really want to, you could try something with SUBSTRING or another MySQL function and try to manipulate the field, but I don't see why you'd want to. It's cumbersome, and it would be an unnecessary ugly hack. On the other hand, it's a puzzle, and people here tend to like puzzles, so if you really want to then post the contents of your field and we can give it a shot.
You can do it like this:
SELECT * FROM table_name WHERE some_field REGEXP '.*"item_key";s:[0-9]+:"item_value".*'
But anyway you should consider storing that data in a separate table.
How about you serialize the value you're searching for?
$sql = sprintf("select * from tbl WHERE serialized_col like '%%%s%%'", serialize($n));
or
$sql = sprintf("select * from tbl WHERE serialized_col like '%s%s%s'", '%', serialize($n), '%');
Working with php serialized data is obviously quite ugly, but I've got this one liner mix of MySQL functions that help to sort that out:
select REPLACE(SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING_INDEX(searchColumn, 'fieldNameToExtract', -1), ';', 2), ':', -1), '"', '') AS extractedFieldName
from tableName as t
having extractedFieldName = 'expressionFilter';
Hope this can help!
Well, i had the same issue, and apparently it's a piece of cake, but maybe it needs more tests.
Simply use the IN statement, but put the field itself as array!
Example:
SELECT id, title, page FROM pages WHERE 2 IN (child_of)
~ where '2' is the value i'm looking for inside the field 'child_of' that is a serialized array.
This serialized array was necessary because I cannot duplicate the records just for storing what id they were children of.
Cheers
If I have attribute_dump field in log table and the value in one of its row has
a:69:{s:9:"status_id";s:1:"2";s:2:"id";s:5:"10215"}
If I want to fetch all rows having status_id is equal to 2, then the query would be
SELECT * FROM log WHERE attribute_dump REGEXP '.*"status_id";s:[0-9]+:"2".*'
There is a good REGEX answer above, but it assumes a key and value implementation. If you just have values in your serialized array, this worked for me:
value only
SELECT * FROM table WHERE your_field_here REGEXP '.*;s:[0-9]+:"your_value_here".*'
key and value
SELECT * FROM table WHERE your_field_here REGEXP '.*"array_key_here";s:[0-9]+:"your_value_here".*'
For easy method use :
column_field_name LIKE %VALUE_TO_BE_SEARCHED_FOR%
in MySQL query
You may be looking for an SQL IN statement.
http://www.w3schools.com/sql/sql_in.asp
You'll have to break your array out a bit first, though. You can't just hand an array off to MySQL and expect it will know what to do with it. For that, you may try serializing it out with PHP's explode.
http://php.net/manual/en/function.explode.php
Select * from table where table_field like '%"enter_your_value"%'
select * from postmeta where meta_key = 'your_key' and meta_value REGEXP ('6')
foreach( $result as $value ) {
$hour = unserialize( $value->meta_value );
if( $hour['date'] < $data['from'] ) {
$sum = $sum + $hour['hours'];
}
}