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  • Syntax Error in MySql StoredProc

    - by karthik
    I am using the below stored proc in mysql to generate the insert statements. I am getting the following error : Script line: 4 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '\’”\’,',’ifnull(‘,column_name,’,””)’,',\’”\’)')) INTO @S' at line 12 What would be the syntax problem in that ? DELIMITER $$ DROP PROCEDURE IF EXISTS `InsGen` $$ CREATE DEFINER=`root`@`localhost` PROCEDURE `InsGen`(in_db varchar(20),in_table varchar(20),in_file varchar(100)) BEGIN declare Whrs varchar(500); declare Sels varchar(500); declare Inserts varchar(2000); declare tablename varchar(20); set tablename=in_table; select tablename; # Comma separated column names – used for Select select group_concat(concat(‘concat(\’”\’,',’ifnull(‘,column_name,’,””)’,',\’”\’)')) INTO @Sels from information_schema.columns where table_schema=’test’ and table_name=tablename; # Comma separated column names – used for Group By select group_concat(‘`’,column_name,’`') INTO @Whrs from information_schema.columns where table_schema=’test’ and table_name=tablename; #Main Select Statement for fetching comma separated table values set @Inserts=concat(“select concat(‘insert into “, in_db,”.”,tablename,” values(‘,concat_ws(‘,’,”,@Sels,”),’);’) from “, in_db,”.”,tablename,” group by “,@Whrs, ” INTO OUTFILE ‘”, in_file ,”‘”); PREPARE Inserts FROM @Inserts; EXECUTE Inserts; END $$ DELIMITER ;

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  • [MYSQL] Select users who own both a dog and a cat

    - by matte
    Hi, I have this sample table: CREATE TABLE `dummy` ( `id` int(11) NOT NULL AUTO_INCREMENT, `userId` int(11) NOT NULL, `pet` varchar(50) NOT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=7 ; INSERT INTO `dummy` (`id`, `userId`, `pet`) VALUES(1, 1, 'dog'); INSERT INTO `dummy` (`id`, `userId`, `pet`) VALUES(2, 1, 'cat'); INSERT INTO `dummy` (`id`, `userId`, `pet`) VALUES(3, 2, 'dog'); INSERT INTO `dummy` (`id`, `userId`, `pet`) VALUES(4, 2, 'cat'); INSERT INTO `dummy` (`id`, `userId`, `pet`) VALUES(5, 3, 'cat'); INSERT INTO `dummy` (`id`, `userId`, `pet`) VALUES(6, 4, 'dog'); How can I write the statements below in mysql: Retrieve all users who own both a dog and a cat Retrieve all users who own a dog or a cat Retrieve all users who own only a cat Retrieve all users who doesn't own a cat Thanks!

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  • mysql real escape string error

    - by user547995
    Code mysql_query("INSERT INTO Account(User, Pw, email) VALUES('mysql_real_escape_string($_POST[user])', '$pw','mysql_real_escape_string($_POST[email]) ) ") or die(mysql_error()); Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''mysql_real_escape_string(123) )' at line 1 Please help

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  • Python Sets vs Lists

    - by mvid
    In Python, which data structure is more efficient/speedy? Assuming that order is not important to me and I would be checking for duplicates anyway, is a Python set slower than a Python list?

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  • atomic operation cost

    - by osgx
    Hello What is the cost of the atomic operation? How much cycles does it consume? Will it pause other processors on SMP or NUMA, or will it block memory accesses? Will it flush reorder buffer in out-of-order CPU? What effects will be on the cache? Thanks.

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  • mySQL - Separate Lastname,Firstname and CompanyName entries from a single column

    - by Decalmo
    I've got a column in a database which contains company names, and customer names all in one field... what I'd like to do is keep the CompanyName column completely intact, but wherever there is a comma in the CompanyName I'd like to take that information and populate it into a FirstName and LastName field. So that basically... Before: CompanyName: Big Company Inc Smith, John Sue, Maggie After: CompanyName: Big Company Inc Smith, John Sue, Maggie LastName: Smith Sue FirstName: John Maggie This one is pretty dang tricky for me... Any help is greatly appreciated!

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  • Speeding Up Slow, CPU-Intensive Scrolling in WinForms

    - by S B
    How can I speed up the scrolling of UserControls in a WinForms app.? My main form has trouble scrolling quickly on slow machines--painting for each of the small scroll increments is CPU intensive. My form has roughly fifty UserControls (with multiple fields) positioned one below the other. I’ve tried intercepting OnScroll and UserPaint in order to eliminate some of the unnecessary re-paints for very small scroll events, but the underlying Paint gets called anyway. How can I streamline scrolling on slower machines?

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  • One large file or multiple small files?

    - by Dan
    I have an application (currently written in Python as we iron out the specifics but eventually it will be written in C) that makes use of individual records stored in plain text files. We can't use a database and new records will need to be manually added regularly. My question is this: would it be faster to have a single file (500k-1Mb) and have my application open, loop through, find and close a file OR would it be faster to have the records separated and named using some appropriate convention so that the application could simply loop over filenames to find the data it needs? I know my question is quite general so direction to any good articles on the topic are as appreciated as much as suggestions. Thanks very much in advance for your time, Dan

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  • Scalable Ticketing / Festival Website

    - by Luke Lowrey
    I've noticed major music festivals (at least in Australia) and other events that experience a peak in traffic when tickets go on sale have huge problems keeping their websites running well. I've seen a few different techniques used to try combat this such as short sessions and virtual queues but they dont seem to have much effect. If you were to design a website to sell a lot of tickets in a short amount of time how would you handle scalability? What technologies and programming techniques would you use?

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  • Shouldn't prepared statements be much faster?

    - by silversky
    $s = explode (" ", microtime()); $s = $s[0]+$s[1]; $con = mysqli_connect ('localhost', 'test', 'pass', 'db') or die('Err'); for ($i=0; $i<1000; $i++) { $stmt = $con -> prepare( " SELECT MAX(id) AS max_id , MIN(id) AS min_id FROM tb "); $stmt -> execute(); $stmt->bind_result($M,$m); $stmt->free_result(); $rand = mt_rand( $m , $M ).'<br/>'; $res = $con -> prepare( " SELECT * FROM tb WHERE id >= ? LIMIT 0,1 "); $res -> bind_param("s", $rand); $res -> execute(); $res->free_result(); } $e = explode (" ", microtime()); $e = $e[0]+$e[1]; echo number_format($e-$s, 4, '.', ''); // and: $link = mysql_connect ("localhost", "test", "pass") or die (); mysql_select_db ("db") or die ("Unable to select database".mysql_error()); for ($i=0; $i<1000; $i++) { $range_result = mysql_query( " SELECT MAX(`id`) AS max_id , MIN(`id`) AS min_id FROM tb "); $range_row = mysql_fetch_object( $range_result ); $random = mt_rand( $range_row->min_id , $range_row->max_id ); $result = mysql_query( " SELECT * FROM tb WHERE id >= $random LIMIT 0,1 "); } defenitly prepared statements are much more safer but also every where it says that they are much faster BUT in my test on the above code I have: - 2.45 sec for prepared statements - 5.05 sec for the secon example What do you think I'm doing wrong? Should I use the second solution or I should try to optimize the prep stmt?

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  • C++: how to truncate the double in efficient way?

    - by Arman
    Hello, I would like to truncate the float to 4 digits. Are there some efficient way to do that? My current solution is: double roundDBL(double d,unsigned int p=4) { unsigned int fac=pow(10,p); double facinv=1.0/static_cast<double>(fac); double x=static_cast<unsigned int>(x*fac)/facinv; return x; } but using pow and delete seems to me not so efficient. kind regards Arman.

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  • MySQL table data transformation -- how can I dis-aggregate MySQL time data?

    - by lighthouse65
    We are coding for a MySQL data warehousing application that stores descriptive data (User ID, Work ID, Machine ID, Start and End Time columns in the first table below) associated with time and production quantity data (Output and Time columns in the first table below) upon which aggregate (SUM, COUNT, AVG) functions are applied. We now wish to dis-aggregate time data for another type of analysis. Our current data table design: +---------+---------+------------+---------------------+---------------------+--------+------+ | User ID | Work ID | Machine ID | Event Start Time | Event End Time | Output | Time | +---------+---------+------------+---------------------+---------------------+--------+------+ | 080025 | ABC123 | M01 | 2008-01-24 16:19:15 | 2008-01-24 16:34:45 | 2120 | 930 | +---------+---------+------------+---------------------+---------------------+--------+------+ Reprocessing dis-aggregation that we would like to do would be to transform table content based on a granularity of minutes, rather than the current production event ("Event Start Time" and "Event End Time") granularity. The resulting reprocessing of existing table rows would look like: +---------+---------+------------+---------------------+--------+ | User ID | Work ID | Machine ID | Production Minute | Output | +---------+---------+------------+---------------------+--------+ | 080025 | ABC123 | M01 | 2010-01-24 16:19 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:20 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:21 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:22 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:23 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:24 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:25 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:26 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:27 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:28 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:29 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:30 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:31 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:22 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:33 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:34 | 133 | +---------+---------+------------+---------------------+--------+ So the reprocessing would take an existing row of data created at the granularity of production event and modify the granularity to minutes, eliminating redundant (Event End Time, Time) columns while doing so. It assumes a constant rate of production and divides output by the difference in minutes plus one to populate the new table's Output column. I know this can be done in code...but can it be done entirely in a MySQL insert statement (or otherwise entirely in MySQL)? I am thinking of a INSERT ... INTO construction but keep getting stuck. An additional complexity is that there are hundreds of machines to include in the operation so there will be multiple rows (one for each machine) for each minute of the day. Any ideas would be much appreciated. Thanks.

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  • taking values from fields

    - by jagadeesh
    there is two table first table is pg_vendor_signup pg_vendor_signup id vendor_id name country_id secound table is pg_vendor_friends vid fid status pg_vendor_signup contain data is 1 3 ramu 381 2 4 raj 381 2 4 usha 381 3 4 krian 381 4 4 manu 381 4 9 aswin 381 pg_vendor_friends countain 1 9 4 0 1 9 3 0 i Want get all name where country id=381 and in pg_vendor_friends get status of table

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  • A question about complex SQL statement

    - by william
    Table A has columns ID and AName, Table B has columns BName and ID. B.ID is foreign key of A.ID. Write a SQL statement to show data like: print column AName and C which describe whether Table B has ID in Table A, if exists 1 or else 0. So if A is: 1 aaa 2 bbb B is: something,2 output is: aaa,0 bbb,1

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  • Of these 3 methods for reading linked lists from shared memory, why is the 3rd fastest?

    - by Joseph Garvin
    I have a 'server' program that updates many linked lists in shared memory in response to external events. I want client programs to notice an update on any of the lists as quickly as possible (lowest latency). The server marks a linked list's node's state_ as FILLED once its data is filled in and its next pointer has been set to a valid location. Until then, its state_ is NOT_FILLED_YET. I am using memory barriers to make sure that clients don't see the state_ as FILLED before the data within is actually ready (and it seems to work, I never see corrupt data). Also, state_ is volatile to be sure the compiler doesn't lift the client's checking of it out of loops. Keeping the server code exactly the same, I've come up with 3 different methods for the client to scan the linked lists for changes. The question is: Why is the 3rd method fastest? Method 1: Round robin over all the linked lists (called 'channels') continuously, looking to see if any nodes have changed to 'FILLED': void method_one() { std::vector<Data*> channel_cursors; for(ChannelList::iterator i = channel_list.begin(); i != channel_list.end(); ++i) { Data* current_item = static_cast<Data*>(i->get(segment)->tail_.get(segment)); channel_cursors.push_back(current_item); } while(true) { for(std::size_t i = 0; i < channel_list.size(); ++i) { Data* current_item = channel_cursors[i]; ACQUIRE_MEMORY_BARRIER; if(current_item->state_ == NOT_FILLED_YET) { continue; } log_latency(current_item->tv_sec_, current_item->tv_usec_); channel_cursors[i] = static_cast<Data*>(current_item->next_.get(segment)); } } } Method 1 gave very low latency when then number of channels was small. But when the number of channels grew (250K+) it became very slow because of looping over all the channels. So I tried... Method 2: Give each linked list an ID. Keep a separate 'update list' to the side. Every time one of the linked lists is updated, push its ID on to the update list. Now we just need to monitor the single update list, and check the IDs we get from it. void method_two() { std::vector<Data*> channel_cursors; for(ChannelList::iterator i = channel_list.begin(); i != channel_list.end(); ++i) { Data* current_item = static_cast<Data*>(i->get(segment)->tail_.get(segment)); channel_cursors.push_back(current_item); } UpdateID* update_cursor = static_cast<UpdateID*>(update_channel.tail_.get(segment)); while(true) { if(update_cursor->state_ == NOT_FILLED_YET) { continue; } ::uint32_t update_id = update_cursor->list_id_; Data* current_item = channel_cursors[update_id]; if(current_item->state_ == NOT_FILLED_YET) { std::cerr << "This should never print." << std::endl; // it doesn't continue; } log_latency(current_item->tv_sec_, current_item->tv_usec_); channel_cursors[update_id] = static_cast<Data*>(current_item->next_.get(segment)); update_cursor = static_cast<UpdateID*>(update_cursor->next_.get(segment)); } } Method 2 gave TERRIBLE latency. Whereas Method 1 might give under 10us latency, Method 2 would inexplicably often given 8ms latency! Using gettimeofday it appears that the change in update_cursor-state_ was very slow to propogate from the server's view to the client's (I'm on a multicore box, so I assume the delay is due to cache). So I tried a hybrid approach... Method 3: Keep the update list. But loop over all the channels continuously, and within each iteration check if the update list has updated. If it has, go with the number pushed onto it. If it hasn't, check the channel we've currently iterated to. void method_three() { std::vector<Data*> channel_cursors; for(ChannelList::iterator i = channel_list.begin(); i != channel_list.end(); ++i) { Data* current_item = static_cast<Data*>(i->get(segment)->tail_.get(segment)); channel_cursors.push_back(current_item); } UpdateID* update_cursor = static_cast<UpdateID*>(update_channel.tail_.get(segment)); while(true) { for(std::size_t i = 0; i < channel_list.size(); ++i) { std::size_t idx = i; ACQUIRE_MEMORY_BARRIER; if(update_cursor->state_ != NOT_FILLED_YET) { //std::cerr << "Found via update" << std::endl; i--; idx = update_cursor->list_id_; update_cursor = static_cast<UpdateID*>(update_cursor->next_.get(segment)); } Data* current_item = channel_cursors[idx]; ACQUIRE_MEMORY_BARRIER; if(current_item->state_ == NOT_FILLED_YET) { continue; } found_an_update = true; log_latency(current_item->tv_sec_, current_item->tv_usec_); channel_cursors[idx] = static_cast<Data*>(current_item->next_.get(segment)); } } } The latency of this method was as good as Method 1, but scaled to large numbers of channels. The problem is, I have no clue why. Just to throw a wrench in things: if I uncomment the 'found via update' part, it prints between EVERY LATENCY LOG MESSAGE. Which means things are only ever found on the update list! So I don't understand how this method can be faster than method 2. The full, compilable code (requires GCC and boost-1.41) that generates random strings as test data is at: http://pastebin.com/e3HuL0nr

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  • Are these tables too big for SQL Server or Oracle

    - by Jeffrey Cameron
    Hey all, I'm not much of a database guru so I would like some advice. Background We have 4 tables that are currently stored in Sybase IQ. We don't currently have any choice over this, we're basically stuck with what someone else decided for us. Sybase IQ is a column-oriented database that is perfect for a data warehouse. Unfortunately, my project needs to do a lot of transactional updating (we're more of an operational database) so I'm looking for more mainstream alternatives. Question Given these tables' dimensions, would anyone consider SQL Server or Oracle to be a viable alternative? Table 1 : 172 columns * 32 million rows Table 2 : 453 columns * 7 million rows Table 3 : 112 columns * 13 million rows Table 4 : 147 columns * 2.5 million rows Given the size of data what are the things I should be concerned about in terms of database choice, server configuration, memory, platform, etc.?

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  • Postcode and radius lookup recommendations

    - by WestDiscGolf
    I look after a number of divisional websites for a uk based membership organisation and what we want to do is provide, as well as other address functions, is a closest member lookup to a web user from the websites themselves. A few use cases that I want to fill: Case 1: The user puts in their post code and wants to see all the members in a 5/10/15/20/30/40 mile radius from them Case 2: The member puts in an area (city, county, etc.) and gets a list of members in that area. Essentially what I'm looking for is a programmable API which I can code against to do: post code lookup and returns addresses (after picking house number for example). search post code + radius (5miles, 10miles etc) and get a set of applicable post codes to then join onto the membership records in the database Any recommendations? It can be a quarterly update install on the server, it can be a queryable web service. I'm open to suggestions. Thanks in advance

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  • PHP behaves weird, mixing up HTML markup.

    - by adardesign
    Thanks for looking on this problem. I have a page that is totally valid page, and there is a PHP loop that brings in a <li> for each entry of the table. When i check this page locally it looks 100% OK, but when veiwing the page online the left side bar (which creates this markup is broken randomly mixing <div>'s and <li>'s and i have no clue what the problem is. See page (problem is on the left side) php code <?php do { ?> <li class="clear-block" id="<?php echo $row_Recordset1['penSKU']; ?>"> <a title="Click to view the <?php echo $row_Recordset1['penName']; ?> collection" rel="<?php echo $row_Recordset1['penSKU']; ?>"> <img src="prodImages/small/<?php echo $row_Recordset1['penSKU']; ?>.png" alt="" /> <div class="prodInfoCntnr"> <div class="basicInfo"> <span class="prodName"><?php echo $row_Recordset1['penName']; ?></span> <span class="prodSku"><?php echo $row_Recordset1['penSKU']; ?></span> </div> <div class="secondaryInfo"> <span>As low as .<?php echo $row_Recordset1['price25000']; ?>¢ <!--<em>(R)</em>--></span> <div class="colorPlacholder" rel="<?php echo $row_Recordset1['penColors']; ?>"></div> </div> </div> <div class="additPenInfo"> <div class="imprintInfo"><span>Imprint area: </span><?php echo $row_Recordset1['imprintArea']; ?></div> <div class="colorInfo"><span>Available in: </span><?php echo $row_Recordset1['penColors']; ?></div> <table border="0" cellspacing="0" cellpadding="0"> <tr> <th>Amount</th> <th>500</th> <th>1,000</th> <th>2,500</th> <th>5,000</th> <th>10,000</th> <th>20,000</th> </tr> <tr> <td>Price <span>(R)</span></td> <td><?php echo $row_Recordset1['price500'];?>¢</td> <td><?php echo $row_Recordset1['price1000'];?>¢</td> <td><?php echo $row_Recordset1['price2500'];?>¢</td> <td><?php echo $row_Recordset1['price5000'];?>¢</td> <td>Please Contact</td> <td>Please Contact</td> </tr> </table> </div> </a> </li> <?php } while ($row_Recordset1 = mysql_fetch_assoc($Recordset1)); ?>

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  • displaying a group once in php mysql

    - by JPro
    I have some data like this : 1 TC1 PASS 2 TC2 FAIL 3 TC3 INCONC 4 TC1 FAIL 5 TC21 FAIL 6 TC4 PASS 7 TC3 PASS 8 TC2 FAIL 9 TC1 TIMEOUT 10 TC21 FAIL If I try the below code : <?php mysql_connect("localhost", "root", "pop") or die(mysql_error()); mysql_select_db("jpd") or die(mysql_error()); $oustanding_fails = mysql_query("select * from SELECT_PASS ") or die(mysql_error()); $resultSetArray = array(); $platform; while($row1 = mysql_fetch_array( $oustanding_fails )) { if(trim($row1['TESTCASE']) <> trim($platform)) { echo $row1['TESTCASE']."-"; $platform = $row1['TESTCASE']; } echo $row1['RESULT'] ."<br>"; } ?> to get a result like this : TC1 PASS FAIL TIMEOUT TC2 FAIL FAIL TC3 INCONC PASS TC4 PASS AND SO ON. I am unable to get the result I want. Any ideas where exactly I am making mistake? Thanks.

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  • Drupal db_query_range sql query

    - by hfidgen
    Hiya, I'm trying to get this working and the query executes but nothing comes back.. I've tried everything I can think of, can you spot what I'm doing wrong? Thanks in advance! $nido = $node->nid; $result = db_query_range(' SELECT i.nid, i.iid, a.fid, p.filename, p.filepath FROM {drup_image_attach} i LEFT JOIN {drup_image} a ON i.iid = a.nid LEFT JOIN {drup_files} p ON a.fid = p.fid WHERE i.nid = %d AND p.filename = "recipe_thumb"', $nido, 0, 10); echo "Filepath = " . $result ->filepath. "<br>"; echo "Filepath = " . $result ->filename . "<br>"; echo "IID = " . $result ->iid. "<br>"; echo "NID = " . $result ->nid . "<br>"; } EDIT - sorted out a couple of bits, but the output is still empty!

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  • [Apache Camel] Generating multiple files based on DB query in a nice way

    - by chantingwolf
    Dear all, I have a following question. I have to generate many files based on sql query. Let's say for example, I have get from database a list of orders made today and genarate file for each order and later store each file on ftp. Ideally I would like to get follewing. Not quite sure how to get it. from(MyBean).to(Ftp) The problem and main question is how to generate multiple messages by custom bean (for example). I am not sure if splitter EIP is ok in this case because in my case I have not just one message to split, but I just have to generate and send many messages. http://camel.apache.org/splitter.html I hope, someone meet this problem before. If the task will be to generate just one file - everything is quite simple - you need just fill Exchange.OutMessage (or something like this). But what about multiple files - I really can't get, how to manage this situation. P.S. Sorry if this question is stupid. I am novice in Camel (working with it just for coupe weeks). It's a great tool. Actually, that's why I want to use in in the best way. Thanks a lot.

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  • clarification on yslow rules

    - by ooo
    i ran yslow and i got a bad score on expires header: Here was the message: Grade F on Add Expires headers There are 45 static components without a far-future expiration date. i am using IIS on a hosted environment. what do i need to do on my css or js files to fix this issue ?

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  • Lazy/deferred loading of a CollectionViewSource?

    - by Shimmy
    When you create a CollectionViewSource in the Resources section, is the set Source loaded when the resources are initalized (i.e. when the Resources holder is inited) or when data is bound? Is there a xamly way to make a CollectionViewSource lazy-load? deferred-load? explicit-load?

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