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  • What Libs should i use to write a packet sniffer in perl

    - by Mouseroot
    I basicly want to write a small packet sniffer in perl im using ubuntu 9 im basically looking to sniff all packets on my nic and return data such as source and destination address as well as the data i looked into Net::Write::Layer2 but i could never get it to run as it says it cannot find the required libs and i cannot find the dependents adn that lib is for writeing data and not accepting it ive read that i should use libpcap but no good examples are available i basicly just need to know what lib i should use and ill find a example/tutorial on using said lib Thanks in Advance

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  • Text piped to PowerShell.exe isn't recieved when using [Console]::ReadLine()

    - by crtracy
    I'm getting itermittent data loss when calling .NET [Console]::ReadLine() to read piped input to PowerShell.exe: >ping localhost | powershell -NonInteractive -NoProfile -C "do {$line = [Console]::ReadLine(); ('' + (Get-Date -f 'HH:mm :ss') + $line) | Write-Host; } while ($line -ne $null)" 23:56:45time<1ms 23:56:45 23:56:46time<1ms 23:56:46 23:56:47time<1ms 23:56:47 23:56:47 Normally 'ping localhost' from Vista64 looks like this, so there is a lot of data missing from the output above: Pinging WORLNTEC02.bnysecurities.corp.local [::1] from ::1 with 32 bytes of data: Reply from ::1: time<1ms Reply from ::1: time<1ms Reply from ::1: time<1ms Reply from ::1: time<1ms Ping statistics for ::1: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 0ms, Maximum = 0ms, Average = 0ms But using the same API from C# recieves all the data sent to the process (excluding some newline differences). Code: namespace ConOutTime { class Program { static void Main (string[] args) { string s; while ((s = Console.ReadLine ()) != null) { if (s.Length > 0) // don't write time for empty lines Console.WriteLine("{0:HH:mm:ss} {1}", DateTime.Now, s); } } } } Output: 00:44:30 Pinging WORLNTEC02.bnysecurities.corp.local [::1] from ::1 with 32 bytes of data: 00:44:30 Reply from ::1: time<1ms 00:44:31 Reply from ::1: time<1ms 00:44:32 Reply from ::1: time<1ms 00:44:33 Reply from ::1: time<1ms 00:44:33 Ping statistics for ::1: 00:44:33 Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), 00:44:33 Approximate round trip times in milli-seconds: 00:44:33 Minimum = 0ms, Maximum = 0ms, Average = 0ms So, if calling the same API from PowerShell instead of C# many parts of StdIn get 'eaten'. Is the PowerShell host reading string from StdIn even though I didn't use 'PowerShell.exe -Command -'?

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  • in django admin, can we have a multiple select based on choices

    - by Rasiel
    http://docs.djangoproject.com/en/dev/ref/models/fields/#choices i've read through the documentation and this implies using a database table for dynamic data, however it states choices is meant for static data that doesn't change much, if ever. so what if i want to use choices, but have it select multiple because the data i'm using is quite static, e.g days of the week. is there anyway to achieve this without a database table?

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  • .NET SerialPort.Read skipps bytes

    - by Lukas Rieger
    Solution Reading the data byte wise via "port.ReadByte" is too slow, the problem is inside the SerialPort class. i changed it to reading bigger chunks via "port.Read" and there are now no buffer overruns. although i found the solution myself, writing it down helped me and maybe someone else has the same problem and finds this via google... (how can i mark it as answered?) EDIT 2 by setting port.ReadBufferSize = 2000000; i can delay the problem for ~30 seconds. so it seems, .Net really is too slow... since my application is not that critical, i just set the buffer to 20MB, but i am still interested in the cause. EDIT i just tested something i had not thought of before (shame on me): port.ErrorReceived += (object self, SerialErrorReceivedEventArgs se_arg) => { Console.Write("| Error: {0} | ", System.Enum.GetName(se_arg.EventType.GetType(), se_arg.EventType)); }; and it seems that i have an overrun. Is the .Net implementation too slow for 500k or is there an error on my side? Original Question i built a very primitive oszilloscope (avr, which sends adc data over uart to an ftdi chip). On the pc side i have a WPF Programm that displays this data. The Protokoll is: two sync bytes (0xaffe) - 14 data bytes - two sync bytes - 14 data bytes - ... i use 16bit values, so inside the 14 data bytes are 7 channels (lsb first). I verified the uC Firmware with hTerm, and it does send and receive everything correct. But, if i try to read the data with C#, sometimes some bytes are lost. The oszilloscop programm is a mess, but i created a small sample application, which has the same symptoms. I added two extension methods to a) read one byte from the COM Port and ignore -1 (EOF) and b) wait for the sync pattern. The sample programm first syncs onto the data stream by waiting for (0xaffe) and then compares the received bytes with the expected values. the loop runs a few times until an assert failed message pops up. I could not find anything about lost bytes via google, any help would be appreciated. Code using System; using System.Collections.Generic; using System.Diagnostics; using System.IO.Ports; using System.Linq; using System.Text; using System.Threading.Tasks; namespace SerialTest { public static class SerialPortExtensions { public static byte ReadByteSerial(this SerialPort port) { int i = 0; do { i = port.ReadByte(); } while (i < 0 || i > 0xff); return (byte)i; } public static void WaitForPattern_Ushort(this SerialPort port, ushort pattern) { byte hi = 0; byte lo = 0; do { lo = hi; hi = port.ReadByteSerial(); } while (!(hi == (pattern >> 8) && lo == (pattern & 0x00ff))); } } class Program { static void Main(string[] args) { //500000 8n1 SerialPort port = new SerialPort("COM3", 500000, Parity.None, 8, StopBits.One); port.Open(); port.DiscardInBuffer(); port.DiscardOutBuffer(); //Sync port.WaitForPattern_Ushort(0xaffe); byte hi = 0; byte lo = 0; int val; int n = 0; // Start Loop, the stream is already synced while (true) { //Read 7 16-bit values (=14 Bytes) for (int i = 0; i < 7; i++) { lo = port.ReadByteSerial(); hi = port.ReadByteSerial(); val = ((hi << 8) | lo); Debug.Assert(val != 0xaffe); } //Read two sync bytes lo = port.ReadByteSerial(); hi = port.ReadByteSerial(); val = ((hi << 8) | lo); Debug.Assert(val == 0xaffe); n++; } } } }

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  • Custom field type:problem in page layout

    - by AB
    I have created a custom field type and its working properly but when I am adding it on page layout ,its not displaying any data in there.I am getting data from one of the list.I have added that field in list and its displaying all the data I want to select but on page layout its blank..... Any idea where i m getting wrong...?

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  • Entity Framework 4 and SQL Compact 4: How to generate database?

    - by David Veeneman
    I am developing an app with Entity Framework 4 and SQL Compact 4, using a Model First approach. I have created my EDM, and now I want to generate a SQL Compact 4.0 database to act as a data store for the model. I bring up the Generate Database Wizard and click the New Connection button to create a connection for the generated file. The Choose Data Source dialog appears, but SQL Compact 4.0 is not listed in the list of available data sources: I am running VS 2010 SP1 (beta) and I have installed the VS 2010 Tools for SQL Compact 4.0. I can create a SQL Compact 4.0 data connection from the Server Explorer. It is only in the Generate Database Wizard that the 4.0 option doesn't appear. BTW, my SQL Compact 4.0 installation does include System.Data.SqlServerCe.Entity.dll. So I should have the SQL Compact components I need. Am I doing something incorrectly, or is this a bug? Does anyone have a fix or a workaround? Thanks for your help.

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  • How to use JQuery to focus on a specific DIV tag?

    - by kwokwai
    Hi all, Say I got a few DIV tags in a HTML page like: <DIV ID="div1"> <Input type="radio" name="data['site1']['user']" VALUE="1">user1<br/> </DIV> <DIV ID="div2"> <Input type="radio" name="data['site1']['user']" VALUE="2">user2<br/> </DIV> <DIV ID="div3"> <Input type="radio" name="data['site1']['user']" VALUE="3">user3<br/> </DIV> <DIV ID="div4"> <Input type="radio" name="data['site1']['user']" VALUE="4">user4<br/> </DIV> Is it possible to do the same effect in JQuery like this: Document.getElementByID('div2').focus();

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  • Why to store username and password in Keychain in iPhone app

    - by Suriya
    I have worked with NSUserDefault but this keychain concept is totally new for me. I have tried looking for similar Questions but couldn't find the exact reason to do so. What I have done: I already know how to store data in NSUserDefault. and also the reason why do we need to store it. Regarding Keychain I just know that storing in keychain stores the data with some extra security by encoding the original text while NSUserDefault stores the data as plain text. Is this the only reason for storing the data in keychain?

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  • protect_from_forgery & Unobtrusive Javascript

    - by Matt Grande
    Hi all, I have some javascript making an ajax call in my Rails site: $.ajax({type: "PUT", url: url, data: { dummy: data }, complete: function(data) {}}); When Rails gets it, it throws back an ActionController::InvalidAuthenticityToken Error. I'd like to keep the protect_from_forgery stuff in there, if possible... But I'm at a loss for how can I pass the auth token from a javascript file? Can anyone help me out?

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  • use pin.title in other class

    - by Marco
    Hello i have implemented the following code: - (void) mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)annView calloutAccessoryControlTapped:(UIControl *)control { name = annView.annotation.title; NSLog(name, [annView description]); } and how can I use the variable name in another class? can you please help me, i am new in iphone developing!

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  • Client-side or server-side processing?

    - by Nick
    So, I'm new to dynamic web design (my sites have been mostly static with some PHP), and I'm trying to learn the latest technologies in web development (which seems to be AJAX), and I was wondering, if you're transferring a lot of data, is it better to construct the page on the server and "push" it to the user, or is it better to "pull" the data needed and create the HTML around it on the clientside using JavaScript? More specifically, I'm using CodeIgniter as my PHP framework, and jQuery for JavaScript, and if I wanted to display a table of data to the user (dynamically), would it be better to format the HTML using CodeIgniter (create the tables, add CSS classes to elements, etc..), or would it be better to just serve the raw data using JSON and then build it into a table with jQuery? My intuition says to do it clientside, as it would save bandwidth and the page would probably load quicker with the new JavaScript optimizations all these browsers have now, however, then the site would break for someone not using JavaScript... Thanks for the help

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  • Matrix in python

    - by Werner
    Hi, I am very new to Python, I need to read numbers from a file and store them in a matrix like I would do it in fortran or C; for i for j data[i][j][0]=read(0) data[i][j][1]=read(1) data[i][j][2]=read(2) ... ... How can I do the same in Python? I read a bit but got confused with tuples and similar things If you could point me to a similar example it would be great thanks

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  • Php JSON Response Array

    - by Nick Kl
    I have this php code. As you can see i query a mysql database through a function showallevents. I return a the $result to the $event variable. I try to return all rows of the data that i take with the msql_fetch_assoc. I don't get response even when i encode the $response variable. It returns null to all fields. Can anyone help me on what i am doing wrong. I had a valid code but it was returning only 1 row of data so i tried to make an associative array but seems i am failing. if ($tag == 'showallevents') { // Request type is show all events // show all events $event = $db->showallevents(); if ($event != false) { $data = array(); while($row = mysql_fetch_assoc($event)) { $data[] = array( $response["success"] = 1, $response["uid"] = $event["uid"], $response["event"]["date"] = $event["date"], $response["event"]["hours"] = $event["hours"], $response["event"]["store_name"] = $event["store_name"], $response["event"]["event_information"] = $event["event_information"], $response["event"]["event_type"] = $event["event_type"], $response["event"]["Phone"] = $event["Phone"], $response["event"]["address"] = $event["address"], $response["event"]["created_at"] = $event["created_at"], $response["event"]["updated_at"] = $event["updated_at"]); } echo json_encode($data); } else { // event not found // echo json with error = 1 $response["error"] = 1; $response["error_msg"] = "Events not found"; echo json_encode($response); } } else { echo "Access Denied"; } } ?>

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  • Hi, how to verify if file exists on windows bat file?

    - by CuSS
    Hi, i have to create a bat file that does this: 1 - If "C:\myprogram\sync\data.handler" exists, exit; 2 - If "C:\myprogram\html\data.sql" doesn't exists, exit; 3 - In "C:\myprogram\sync\" delete all files and folders except ('test','test3' and 'test2') 4 - Copy "C:\myprogram\html\data.sql" to "C:\myprogram\sync\" 5 - Call other bat file w/ option "sync.bat myprogram.ini". If it was in bash enviroment it was easy for me, but i don't know how to test if a file or folder exists and if it is a file or folder :/ Thanks

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  • Commercial web application--scalable database design

    - by Rob Campbell
    I'm designing a set of web apps to track scientific laboratory data. Each laboratory has several members, each of whom will access both their own data and that of their laboratory as a whole. Many typical queries will thus be expected to return records of multiple members (e.g. my mouse, joe's mouse and sally's mouse). I think I have the database fairly well normalized. I'm now wondering how to ensure that users can efficiently access both their own data and their lab's data set when it is mixed among (hopefully) a whole ton of records from other labs. What I've come up with so far is that most tables will end with two fields: user_id and labgroup_id. The WHERE clause of any SELECT statement will include the appropriate reference to one of the id fields ("...WHERE 'labroup_id=n..." or "...WHERE user_id=n..."). My questions are: Is this an approach that will scale to 10^6 or more records? If so, what's the best way to use these fields in a query so that it most efficiently searches the relevant subset of the database? e.g. Should the first step in querying be to create a temporary table containing just the labgroup's data? Or will indexing using some combination of the id, user_id, and labroup_id fields be sufficient at that scale? I thank any responders very much in advance.

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  • Is File good for Interprocess communication

    - by Karthik
    Hi, I have an EXE and DLL running in different process. From DLL I have to send large of amount of data to EXE, which would vary from 50 chars to 2000 chars and more(The data is recordid of records saved in DB). I thought about two options to do that: 1. Using SendMessage- In which data's will be sent in batch. 2. Use an Intermediate file to transfer data. Can anyone list out the pros and cons of methods. I have developed my components using C#.NET Thanks you folks.

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  • problem with fifos linux

    - by nunos
    I am having problem debugging why n_bytes in read_from_fifo function in client.c doesn't correspond to the value written to the fifo. It should only write 25 bytes but it tries to read a lot more (1836020505 bytes (!) to be exact). Any idea why this is happening? server.c: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <unistd.h> #include <fcntl.h> #include <sys/wait.h> #include <signal.h> #include <pthread.h> #include <sys/stat.h> typedef enum { false, true } bool; //first read the int with the number of bytes the data will have //then read that number of bytes bool read_from_fifo(int fd, char* var) { int n_bytes; if (read(fd, &n_bytes, sizeof(int))) { printf("going to read %d bytes\n", n_bytes); if (read(fd, var, n_bytes)) printf("read var\n"); else { printf("error in read var. errno: %d\n", errno); exit(-1); } } return true; } int main() { mkfifo("/tmp/foo", 0660); int fd = open("/tmp/foo", O_RDONLY); char var[100]; read_from_fifo(fd, var); printf("var: %s\n", var); return 0; } client.c: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #include <unistd.h> #include <fcntl.h> typedef enum { false, true } bool; //first write to fd a int with the number of bytes that will be written afterwards bool write_to_fifo(int fd, char* data) { int n_bytes = (strlen(data)) * sizeof(char); printf("going to write %d bytes\n", n_bytes); if (write(fd, &n_bytes, sizeof(int) != -1)) if (write(fd, data, n_bytes) != -1) return true; return false; } int main() { int fd = open("/tmp/foo", O_WRONLY); char data[] = "some random string abcdef"; write_to_fifo(fd, data); return 0; } Help is greatly appreciated. Thanks in advance.

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  • How do you set the "global delimiter" in Excel using VBA (or unicorns)?

    - by DanM
    I've noticed that if I use the text-to-columns feature with comma as the delimiter, any comma-delimited data I paste into Excel after that will be automatically split into columns. This makes me think Excel must have some kind of global delimiter. If this is true, how would I set this global delimiter using Excel VBA? Is it possible to do this directly, or do I need to "trick" Excel by doing a text-to-columns on some junk data, then delete the data? My ultimate goal is to be able to paste in a bunch of data from different files using a macro, and have Excel automatically split it into columns according to the delimiter I set.

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  • Stack Overflow problem transforming with a custom xslt

    - by Flynn1179
    I've got a system that allows the user the option of providing their own XSLT to apply to some data that's been retrieved, as a means of specifying how that data should be presented. However, if the user includes code in the XSLT equivalent to: <xsl:template match="/"> <xsl:element name="data"> <xsl:apply-templates select="." /> </xsl:element> </xsl:template> this causes .NET to infinitely recurse trying to process it, and produces a stack overflow error. I need to be able to trap this before it crashes the app, as the data that's been retrieved is occasionally quite time-consuming to obtain, and the data is lost when this happens. Is there any way of doing this? I know it's theoretically possible to identify any occurrences of xsl:apply-templates with "." in the select attribute, but this isn't the only way an infinite recursion could happen, I need a way of generically trapping it.

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  • Advice/suggestions for my first project PHP Classes

    - by Philip
    Hi guys, Any advice is welcome! I have a very limited understanding of php classes but below is my starting point for the route I would like to take. The code is a reflection of what I see in my head and how I would like to go about business. Does my code even look ok, or am I way off base? What are your thoughts, how would you go about achieving such a task as form-validate-insertquery-sendmail-return messages and errors? Please try and keep your answers simple enough for me to digest as for me its about understanding whats going on and not just a copy/paste job. Kindest regards, Phil. Note: This is a base structure only, no complete code added. <?php //======================================= //class.logging.php //======================================== class logging { public $data = array(); public $errors = array(); function __construct() { array_pop($_POST); $this->data =($this->_logging)? is_isset(filterStr($_POST) : ''; foreach($this->data as $key=> $value) { $this->data[$key] = $value; } //print_r($this->data); de-bugging } public function is_isset($str) { if(isset($str)) ? true: false; } public function filterStr($str) { return preg_match(do somthing, $str); } public function validate_post() { try { if(!is_numeric($data['cardID'])) ? throw new Exception('CardID must be numeric!') : continue; } catch (Exception $e) { return $errors = $e->getCode(); } } public function showErrors() { foreach($errors as $error => $err) { print('<div class="notok"></div><br />'); } } public function insertQ() { $query = ""; } } //======================================= //Usercp.php //======================================== if(isset($_GET['mode'])) { $mode = $_GET['mode']; } else { $mode = 'usercp'; } switch($mode) { case 'usercp': echo 'Welcome to the User Control Panel'; break; case 'logging': require_once 'class.logging.php'; $logger = new logging(); if(isset($_POST['submit']) { if($logger->validate_post === true) { $logger->insertQ(); require_once '/scripts/PHPMailer/class.phpmailer.php'; $mailer = new PHPMailer(); $mailer->PHPMailer(); } else { echo ''.$logger->showErrors.''; } } else { echo ' <form action="'.$_SERVER['PHP_SELF'].'?mode=logging" method="post"> </form> '; } break; case 'user_logout': // do somthing break; case 'user_settings': // do somthing break; ?>

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  • Cannot read app.config, why???

    - by user46503
    Hello, I'm trying to get data from app.config and I always get zero. The App.config is here: <?xml version="1.0" encoding="utf-8"?> <configuration> <connectionStrings> <add name="ExplorerContext" connectionString="metadata=res://*/ExplorerData.csdl|res://*/ExplorerData.ssdl|res://*/ExplorerData.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=MYT\SQLEXPRESS;Initial Catalog=Explorer;Integrated Security=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" /> </connectionStrings> </configuration> Could someone explain what is wrong, why I cannot get the values, System.Configuration.ConfigurationManager.AppSettings.Count is always 0 Thanks

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  • Add C pointer to NSMutableArray

    - by Georges Oates Larsen
    I am writing an Objective-C program that deals with low level image memory. I am using ANSI-C structs for my data storage -- Full blown objects seem overkill seeing as the data I am storing is 100% data, with no methods to operate on that data. Specifically, I am writing a customizable posterization algorithm which relies on an array of colors -- This is where things get tricky. I am storing my colors as structs of three floats, and an integer flag (related to the posterization algorithm specifically). Everyhting is going well, except for one thing... [actual question] I can't figure out how to add pointers to an NSMutableArray! I know how to add an object, but adding a pointer to a struct seems to be more difficult -- I do not want NSMutableArray dereferencing my pointer and treating the struct as some sort of strange object. I want NSMutableArray to add the pointer its self to its collection. How do I go about doing this? Thanks in advance, G

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  • Hibernate @Transactional not starting transaction

    - by rhinds
    I have a web app using Hibernate, and I am attempting to persist some data, but it is failing to persist within a Transaction despite using the @Transactional annotation. My service class is as follows: @Service("profileService") public class ProfileService { private EntityManager entityManager; @Autowired private AccountService accountService; @Autowired private ProfileDAOImpl profileDao; @PersistenceContext public void setEntityManager(EntityManager em) { this.entityManager = em; } @Transactional public void addConnectionToAccount(SocialConnection sc) { entityManager.persist(sc); } } The addConnectionToAccount() method is being called from another Spring bean in a normal method, and the ProfileService class is currently being injected there: public class HibernateConnectionRepository implements ConnectionRepository { @Inject private ProfileService profileService; @Override @Transactional public void addConnection(SocialConnection sc) { try { profileService.addConnectionToAccount(accountId, sc); } catch (Exception e) { e.printStackTrace(); } } I tried putting the @Transactional annotation on the calling method in the vain hope that it might make a difference but nothing. Previously I have experienced problems like this its been because the object being persisted does not satisfy table restrictions (such as non-nullable columns as null) or because the method is being called from within the same class and the calling method is not Transactional, but neither of those are the case here.. Any ideas? it just fails silently, the logs are as follows: 2012-03-26 22:25:04,702 [http-bio-8085-exec-9] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - trace com.mchange.v2.resourcepool.BasicResourcePool@1bc25c8 [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@e5b006) 2012-03-26 22:25:04,710 [http-bio-8085-exec-9] DEBUG org.hibernate.SQL - select SEQ_COUNT from SEQUENCE where SEQ_NAME = 'PO_SEQ' for update 2012-03-26 22:25:04,711 [http-bio-8085-exec-9] DEBUG org.hibernate.SQL - update SEQUENCE set SEQ_COUNT = ? where SEQ_COUNT = ? and SEQ_NAME = 'PO_SEQ' 2012-03-26 22:25:04,723 [http-bio-8085-exec-9] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - trace com.mchange.v2.resourcepool.BasicResourcePool@1bc25c8 [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@e5b006) 2012-03-26 22:25:04,723 [http-bio-8085-exec-9] DEBUG org.hibernate.event.internal.AbstractSaveEventListener - Generated identifier: 2200, using strategy: org.hibernate.id.MultipleHiLoPerTableGenerator UPDATE Also wanted to mention that the HibernateConnectionRepository bean is not annotated and is actually being configured in an @Configuration class (if this makes any difference? not used @Configuration classes much). The method to create the bean is as follows: @Bean @Scope(value = "request", proxyMode = ScopedProxyMode.INTERFACES) public ConnectionRepository connectionRepository() { Authentication authentication = SecurityContextHolder.getContext().getAuthentication(); if (authentication == null) { throw new IllegalStateException("Unable to get a ConnectionRepository: no user signed in"); } ApplicationUser user = (ApplicationUser) authentication.getPrincipal(); return usersConnectionRepository().createConnectionRepository(String.valueOf(user.getAccountId())); } The bean is scoped to the logged in user, but may also be created multiple times for each user..

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  • MongoDB efficient dealing with embedded documents

    - by Sebastian Nowak
    I have serious trouble finding anything useful in Mongo documentation about dealing with embedded documents. Let's say I have a following schema: { _id: ObjectId, ... data: [ { _childId: ObjectId // let's use custom name so we can distinguish them ... } ] } What's the most efficient way to remove everything inside data for particular _id? What's the most efficient way to remove embedded document with particular _childId inside given _id? What's the performance here, can _childId be indexed in order to achieve logarithmic (or similar) complexity instead of linear lookup? If so, how? What's the most efficient way to insert a lot of (let's say a 1000) documents into data for given _id? And like above, can we get O(n log n) or similar complexity with proper indexing? What's the most efficient way to get the count of documents inside data for given _id?

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