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  • How to programmatically fill a database

    - by Dwaine Bailey
    Hi There, I currently have an iPhone app that reads data from an external XML file at start-up, and then writes this data to the database (it only reads/writes data that the user's app has not seen before, though) My concern is that there is going to be a back catalogue of data of several years, and that the first time the user runs the app it will have to read this in and be atrociously slow. Our proposed solution is to include this data "pre-built" into the applications database, so that it doesn't have to load in the archival data on first-load - that is already in the app when they purchase it. My question is whether there is a way to automatically populate this data with data from, say, an XML file or something. The database is in SQLite. I would populate it by hand, but obviously this will take a very long time, so I was just wondering if anybody had a more...programmatic solution...

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  • How to update a table using a select group by in a second one as the data source in MySQL?

    - by Jader Dias
    I can't do this in MySQL UPDATE tableA, tableB SET tableA.column1 = SUM(tableB.column2) WHERE tableA.column3 = tableB.column4 GROUP BY tableB.column4 ; Neither can I UPDATE tableA, ( SELECT SUM(tableB.column2) sumB, tableB.column4 FROM tableB GROUP BY tableB.column4 ) t1 SET tableA.column1 = sumB WHERE tableA.column3 = column4 ; Besides it being illegal code, I think you can understand what I tried to do with the queries above. Both of them had the same intent. How can I do that in MySQL?

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  • What's the pattern for a JSONP method that was initiated from a jQuery plugin?

    - by michielvoo
    I'm writing a jQuery plugin to render data retrieved from another domain in an element on the page. I follow the typical pattern for my jQuery plugin: $(selector).Plugin(options); In the plugin I get external data using jQuery.getScript(url, [success]). The external data source allows me to define the name of a method and it will wrap the data in a call to that method (JSONP): $.getScript("http://www.example.com/data?callback=global_callback", instance_callback); This effectively results in: <script type="text/javascript"> global_callback(data); </script> The scope of global_callback limits what the Plugin instance can do with the data. And the global_callback method has no knowledge of the selector or options that the plugin was instantiated with. I was thinking that global_callback would just store the data, and the plugin would retrieve the data in instance_callback. But I need to make sure that instance_callback will retrieve the correct data, I foresee a problem with multiple instances of the Plugin. How can I handle this? Thanks!

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  • How to feed data over STDIN to multiple external commands in ruby.

    - by Erik
    This question is a bit like my previous (answered) question: How to run multiple external commands in the background in ruby. But, in this case I am looking for a way to feed ruby strings over STDIN to external processes, something like this (the code below is not valid but illustrates my goal): #!/usr/bin/ruby str1 = 'In reality a relatively large string.....' str2 = 'Another large string' str3 = 'etc..' spawn 'some_command.sh', :stdin => str1 spawn 'some_command.sh', :stdin => str2 spawn 'some_command.sh', :stdin => str3 Process.waitall

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  • What's the best way to retrieve two pieces of data from an XML file?

    - by Morinar
    I've got an XML document that is in either a pre or post FO transformed state that I need to extract some information from. In the pre-case, I need to pull out two tags that represent the pageWidth and pageHeight and in the post case I need to extract the page-height and page-width parameters from a specific tag (I forget which one it is off the top of my head). What I'm looking for is an efficient/easily maintainable way to grab these two elements. I'd like to only read the document a single time fetching the two things I need. I initially started writing something that would use BufferedReader + FileReader, but then I'm doing string searching and it gets messy when the tags span multiple lines. I then looked at the DOMParser, which seems like it would be ideal, but I don't want to have to read the entire file into memory if I could help it as the files could potentially be large and the tags I'm looking for will nearly always be close to the top of the file. I then looked into SAXParser, but that seems like a big pile of complicated overkill for what I'm trying to accomplish. Anybody have any advice? Or simple implementations that would accomplish my goal? Thanks.

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  • Is the Keychain suitable for storing general data, such as strings?

    - by cannyboy
    The Keychain seems to be used a lot for usernames and passwords, but is it a good idea to use it for other sensitive stuff (bank details, ID numbers etc), but with no password? What kind of encryption does the keychain use? The scenario I'm concerned about is a thief acquiring an iPhone (which is screen-locked) and being able to access the file system to get this info. Also, would using the Keychain involve export restrictions due to the use of encryption?

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  • How to pass special characters so ASP.NET MVC can handle correctly query string data?

    - by labilbe
    Hello, I am using a route like this one: routes.MapRoute("Invoice-New-NewCustomer", "Invoice/New/Customer/New/{*name}", new { controller = "Customer", action = "NewInvoice" }, new { name = @"[^\.]*" }); There is an action which handles this route: public ActionResult NewInvoice(string name) { AddClientSideValidation(); CustomerViewData viewData = GetNewViewData(); viewData.InvoiceId = "0"; viewData.Customer.Name = name; return View("New", viewData); } When I call return RedirectToAction("NewInvoice", "Customer", new {name}); and name is equal to "The C# Guy", the "name" parameter is truncated to "The C". So my question is : What is the best way to handle this kind of special character with ASP.NET MVC? Thanks!

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  • How to Store data without using Database and how to retrieve them ?

    - by Harikrishna
    I am parsing the html file to extract tabular information through column names. And I want like let user give the input for column name. And according to that column names tabular information will be extracted. Now that column names which user will input,based on that column names I want to find the tabular information from the html file. But where I should store this column names input by user ? And how to retrieve them ? I dont want to use database.

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  • Dynamically removing records when certain columns = 0; data cleansing

    - by cdburgess
    I have a simple card table: CREATE TABLE `users_individual_cards` ( `id` int(11) NOT NULL AUTO_INCREMENT, `user_id` char(36) NOT NULL, `individual_card_id` int(11) NOT NULL, `own` int(10) unsigned NOT NULL, `want` int(10) unsigned NOT NULL, `trade` int(10) unsigned NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `user_id` (`user_id`,`individual_card_id`), KEY `user_id_2` (`user_id`), KEY `individual_card_id` (`individual_card_id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1; I have ajax to add and remove the records based on OWN, WANT, and TRADE. However, if the user removes all of the OWN, WANT, and TRADE cards, they go to zero but it will leave the record in the database. I would prefer to have the record removed. Is checking after each "update" to see if all the columns = 0 the only way to do this? Or can I set a conditional trigger with something like: //psuedo sql AFTER update IF (OWN = 0, WANT = 0, TRADE = 0) DELETE What is the best way to do this? Can you help with the syntax?

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  • How can I automatically generate sql update scripts when some data is updated ?

    - by Brann
    I'd like to automatically generate an update script each time a value is modified in my database. In other words, if a stored procedure, or a query, or whatever updates column a with value b in table c (which as a pk column (i,j...k), I want to generate this : update c set a=b where i=... and j=... and k=... and store it somewhere (for example as a raw string in a table). To complicate things, I want the script to be generated only if the update has been made by a specific user. Good news is that I've got a primary key defined for all my tables. I can see how to do this using a trigger, but I would need to generate specific triggers for each table, and to update them each and every-time my schema changes. I guess there are some built-in ways to do this as SQL server sometimes need to store this kind of things (while using transactional replication for example), but couldn't find anything so far ... any ideas ? I'm also interested in ways to automatically generate triggers (probably using triggers - meta triggers, huh? - since I will need to update triggers automatically when the schema change)

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  • Decryption Key value not match

    - by Jitendra Jadav
    public class TrippleENCRSPDESCSP { public TrippleENCRSPDESCSP() { } public void EncryptIt(string sData,ref byte[] sEncData,ref byte[] Key1,ref byte[] Key2) { try { // Create a new TripleDESCryptoServiceProvider object // to generate a key and initialization vector (IV). TripleDESCryptoServiceProvider tDESalg = new TripleDESCryptoServiceProvider(); // Create a string to encrypt. // Encrypt the string to an in-memory buffer. byte[] Data = EncryptTextToMemory(sData,tDESalg.Key,tDESalg.IV); sEncData = Data; Key1 = tDESalg.Key; Key2 = tDESalg.IV; } catch (Exception) { throw; } } public string DecryptIt(byte[] sEncData) { //byte[] toEncrypt = new ASCIIEncoding().GetBytes(sEncData); //XElement xParser = null; //XmlDocument xDoc = new XmlDocument(); try { //string Final = ""; string sPwd = null; string sKey1 = null; string sKey2 = null; //System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding(); string soutxml = ""; //soutxml = encoding.GetString(sEncData); soutxml = ASCIIEncoding.ASCII.GetString(sEncData); sPwd = soutxml.Substring(18, soutxml.LastIndexOf("</EncPwd>") - 18); sKey1 = soutxml.Substring(18 + sPwd.Length + 15, soutxml.LastIndexOf("</Key1>") - (18 + sPwd.Length + 15)); sKey2 = soutxml.Substring(18 + sPwd.Length + 15 + sKey1.Length + 13, soutxml.LastIndexOf("</Key2>") - (18 + sPwd.Length + 15 + sKey1.Length + 13)); //xDoc.LoadXml(soutxml); //xParser = XElement.Parse(soutxml); //IEnumerable<XElement> elemsValidations = // from el in xParser.Elements("EmailPwd") // select el; #region OldCode //XmlNodeList objXmlNode = xDoc.SelectNodes("EmailPwd"); //foreach (XmlNode xmllist in objXmlNode) //{ // XmlNode xmlsubnode; // xmlsubnode = xmllist.SelectSingleNode("EncPwd"); // xmlsubnode = xmllist.SelectSingleNode("Key1"); // xmlsubnode = xmllist.SelectSingleNode("Key2"); //} #endregion //foreach (XElement elemValidation in elemsValidations) //{ // sPwd = elemValidation.Element("EncPwd").Value; // sKey1 = elemValidation.Element("Key1").Value; // sKey2 = elemValidation.Element("Key2").Value; //} //byte[] Key1 = encoding.GetBytes(sKey1); //byte[] Key2 = encoding.GetBytes(sKey2); //byte[] Data = encoding.GetBytes(sPwd); byte[] Key1 = ASCIIEncoding.ASCII.GetBytes(sKey1); byte[] Key2 = ASCIIEncoding.ASCII.GetBytes(sKey2); byte[] Data = ASCIIEncoding.ASCII.GetBytes(sPwd); // Decrypt the buffer back to a string. string Final = DecryptTextFromMemory(Data, Key1, Key2); return Final; } catch (Exception) { throw; } } public static byte[] EncryptTextToMemory(string Data,byte[] Key,byte[] IV) { try { // Create a MemoryStream. MemoryStream mStream = new MemoryStream(); // Create a CryptoStream using the MemoryStream // and the passed key and initialization vector (IV). CryptoStream cStream = new CryptoStream(mStream, new TripleDESCryptoServiceProvider().CreateEncryptor(Key, IV), CryptoStreamMode.Write); // Convert the passed string to a byte array. //byte[] toEncrypt = new ASCIIEncoding().GetBytes(Data); byte[] toEncrypt = ASCIIEncoding.ASCII.GetBytes(Data); // Write the byte array to the crypto stream and flush it. cStream.Write(toEncrypt, 0, toEncrypt.Length); cStream.FlushFinalBlock(); // Get an array of bytes from the // MemoryStream that holds the // encrypted data. byte[] ret = mStream.ToArray(); // Close the streams. cStream.Close(); mStream.Close(); // Return the encrypted buffer. return ret; } catch (CryptographicException e) { MessageBox.Show("A Cryptographic error occurred: {0}", e.Message); return null; } } public static string DecryptTextFromMemory(byte[] Data, byte[] Key, byte[] IV) { try { // Create a new MemoryStream using the passed // array of encrypted data. MemoryStream msDecrypt = new MemoryStream(Data); // Create a CryptoStream using the MemoryStream // and the passed key and initialization vector (IV). CryptoStream csDecrypt = new CryptoStream(msDecrypt, new TripleDESCryptoServiceProvider().CreateDecryptor(Key, IV), CryptoStreamMode.Write); csDecrypt.Write(Data, 0, Data.Length); //csDecrypt.FlushFinalBlock(); msDecrypt.Position = 0; // Create buffer to hold the decrypted data. byte[] fromEncrypt = new byte[msDecrypt.Length]; // Read the decrypted data out of the crypto stream // and place it into the temporary buffer. msDecrypt.Read(fromEncrypt, 0, msDecrypt.ToArray().Length); //csDecrypt.Close(); MessageBox.Show(ASCIIEncoding.ASCII.GetString(fromEncrypt)); //Convert the buffer into a string and return it. return new ASCIIEncoding().GetString(fromEncrypt); } catch (CryptographicException e) { MessageBox.Show("A Cryptographic error occurred: {0}", e.Message); return null; } } }

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  • Do you use enums in your data applications and how?

    - by Ivan
    My practice shows that a general enterprise application has a lot of entities which's nature corresponds to an elementary enumeration. For example We may have an Order entity which may have such fields as "OrderType", "OrderStatus", "Currency", etc. referencing corresponding Entities which are nothing more than just a textual name bound to a key to be referenced. Using enums would look very natural here. But entities have to be defined in application code at design-time, am I right? While in we need to be able to CRUD enum value variants at runtime and use enums in server-side SQL queries (like stored procedures and views). What are you practices and thoughts on this subject? I am particularly interested in C#4, linq and T-SQL.

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  • Data Modeling Help - Do I add another table, change existing table's usage, or something else?

    - by StackOverflowNewbie
    Assume I have the following tables and relationships: Person - Id (PK) - Name A Person can have 0 or more pets: Pet - Id (PK) - PersonId (FK) - Name A person can have 0 or more attributes (e.g. age, height, weight): PersonAttribute _ Id (PK) - PersonId (FK) - Name - Value PROBLEM: I need to represent pet attributes, too. As it turns out, these pet attributes are, in most cases, identical to the attributes of a person (e.g. a pet can have an age, height, and weight too). How do I represent pet attributes? Do I create a PetAttribute table? PetAttribute Id (PK) PetId (FK) Name Value Do I change PersonAttribute to GenericAttribute and have 2 foreign keys in it - one connecting to Person, the other connecting to Pet? GenericAttribute Id (PK) PersonId (FK) PetId (FK) Name Value NOTE: if PersonId is set, then PetId is not set. If PetId is set, PersonId is not set. Do something else?

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  • How does Python differentiate between the different data types?

    - by wrongusername
    Sorry if this is quite noobish to you, but I'm just starting out to learn Python after learning C++ & Java, and I am wondering how in the world I could just declare variables like id = 0 and name = 'John' without any int's or string's in front! I figured out that perhaps it's because there are no ''s in a number, but how would Python figure that out in something like def increase(first, second) instead of something like int increase(int first, int second) in C++?!

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  • Python's asyncore to periodically send data using a variable timeout. Is there a better way?

    - by Nick Sonneveld
    I wanted to write a server that a client could connect to and receive periodic updates without having to poll. The problem I have experienced with asyncore is that if you do not return true when dispatcher.writable() is called, you have to wait until after the asyncore.loop has timed out (default is 30s). The two ways I have tried to work around this is 1) reduce timeout to a low value or 2) query connections for when they will next update and generate an adequate timeout value. However if you refer to 'Select Law' in 'man 2 select_tut', it states, "You should always try to use select() without a timeout." Is there a better way to do this? Twisted maybe? I wanted to try and avoid extra threads. I'll include the variable timeout example here: #!/usr/bin/python import time import socket import asyncore # in seconds UPDATE_PERIOD = 4.0 class Channel(asyncore.dispatcher): def __init__(self, sock, sck_map): asyncore.dispatcher.__init__(self, sock=sock, map=sck_map) self.last_update = 0.0 # should update immediately self.send_buf = '' self.recv_buf = '' def writable(self): return len(self.send_buf) > 0 def handle_write(self): nbytes = self.send(self.send_buf) self.send_buf = self.send_buf[nbytes:] def handle_read(self): print 'read' print 'recv:', self.recv(4096) def handle_close(self): print 'close' self.close() # added for variable timeout def update(self): if time.time() >= self.next_update(): self.send_buf += 'hello %f\n'%(time.time()) self.last_update = time.time() def next_update(self): return self.last_update + UPDATE_PERIOD class Server(asyncore.dispatcher): def __init__(self, port, sck_map): asyncore.dispatcher.__init__(self, map=sck_map) self.port = port self.sck_map = sck_map self.create_socket(socket.AF_INET, socket.SOCK_STREAM) self.bind( ("", port)) self.listen(16) print "listening on port", self.port def handle_accept(self): (conn, addr) = self.accept() Channel(sock=conn, sck_map=self.sck_map) # added for variable timeout def update(self): pass def next_update(self): return None sck_map = {} server = Server(9090, sck_map) while True: next_update = time.time() + 30.0 for c in sck_map.values(): c.update() # <-- fill write buffers n = c.next_update() #print 'n:',n if n is not None: next_update = min(next_update, n) _timeout = max(0.1, next_update - time.time()) asyncore.loop(timeout=_timeout, count=1, map=sck_map)

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  • Is it Secure to Grant Apache User Ownership of Directories & Files for Wordpress

    - by Oudin
    I'm currently setting up WordPress on an Ubuntu server 12 everything runs fine but there is an issue when it comes to automatically updating and uploading media via WP as Apache "www-data" user does not have permissions to write to the directories. "user1" has full permission All my directories have permissions of 0755 and files 644 my directories setup is as follows: /home/user1/public_html All WP files and directories are in "public_html" In order to work around the auto updating and uploading media I've granted Apache user ownership to the following directories sudo chown www-data:www-data wp-content -R sudo chown www-data:www-data wp-includes -R sudo chown www-data:www-data wp-admin -R I would like to know security wise how secure this is and if it is not secure what would be the best solution? That will allow me to keep all files and directories owned by user1 and still allow wp to be able to automatically update and uploading media

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  • [Sql-Server]what data type to use for password salt and hash values and what length?

    - by Pandiya Chendur
    I am generating salt and hash values from my passwords by using, string salt = CreateSalt(TxtPassword.Text.Length); string hash = CreatePasswordHash(TxtPassword.Text, salt); private static string CreateSalt(int size) { //Generate a cryptographic random number. RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider(); byte[] buff = new byte[size]; rng.GetBytes(buff); // Return a Base64 string representation of the random number. return Convert.ToBase64String(buff); } private static string CreatePasswordHash(string pwd, string salt) { string saltAndPwd = String.Concat(pwd, salt); string hashedPwd = FormsAuthentication.HashPasswordForStoringInConfigFile( saltAndPwd, "sha1"); return hashedPwd; } What datatype you would suggest for storing these values in sql server? Any suggestion... Salt:9GsPWpFD Hash:E778AF0DC5F2953A00B35B35D80F6262CDBB8567

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  • XSL: Parsing XML to HTML - How do I use value-of an element data as an html attribute?

    - by AtomR
    <input src="LOGO.JPG" type="image" name="imagem"> I have an xml element that contains the image path that needs to be displayed in HTML after the parse. <xsl:value-of select="image"/> returns the string that is stored in the image element but how can I use it to make that string be the src atribute value in an html tag? I tried <input src="<xsl:value-of select="image"/>" type="image" name="imagem"> but obviously that doesn't work so how can it be done? I hope I was clear in my question. Please help!

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