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  • jQuery validate + ajaxSubmit on multiple forms

    - by demogar
    Hello there. I'm trying to validate multiple forms in one single page with the jQuery validation plugin but it validates only the first form in the page. Here is my code: $('form.reply_form').validate({ submitHandler: function(form) { $(form).ajaxSubmit(optionsReplies); return false; } }); Is for a list of reply forms in the page (image facebook). If I try to use the third form, for example, it validates the first one and if the first one is blank it wont submit. Thank you in advance.

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  • Rails / JBuilder - Entity array with has_many attributes

    - by seufagner
    I have two models, Person and Image and I want return an json array of Persons with your Images. But I dont want return all Image attributes, but produces a different result. Code below: class Person < ActiveRecord::Base has_many :images, as: :imageable validates :name, presence: true accepts_nested_attributes_for :images, :reject_if => lambda { |img| img['asset'].blank? } end class Image < ActiveRecord::Base belongs_to :imageable, polymorphic: true mount_uploader :asset, ImageUploader validates :asset, presence: true end zzz.jbuilder.json template json.persons(@rodas, :id, :name, :images) json produced: { "rodas": [{ "id": 4, "name": "John", "images": [ { "asset": { "url": "/uploads/image/xxxx.png" } }, { "asset": { "url": "/uploads/image/yyyyy.jpeg" } } ]}, { "id": 19, "name": "Mary", "images": [ { "asset": { "url": "/uploads/image/kkkkkkk.png" } } ] }] } I want something like: { "rodas": [ { "id": 4, "name": "John", "images": [ "/uploads/image/xxxx.png" , "/uploads/image/yyyy.jpeg" ] }, { "id": 10, "name": "Mary", "images": [ "/uploads/image/dddd.png" , "/uploads/image/xxxx.jpeg" ] } ]}

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  • IE7 not digesting JSON: "parse error"

    - by Kenny Leu
    While trying to GET a JSON, my callback function is NOT firing. $.ajax({ type:"GET", dataType:'json', url: myLocalURL, data: myData, success: function(returned_data){alert('success');} }); The strangest part of this is that my JSON(s) validates on JSONlint this ONLY fails on IE7...it works in Safari, Chrome, and all versions of Firefox. If I use 'error', then it reports "parseError"...even though it validates! Is there anything that I'm missing? Does IE7 not process certain characters, data structures (my data doesn't have anything non-alphanumeric, but it DOES have nested JSONs)? I have used tons of other AJAX calls that all work (even in IE7), but with the exception of THIS call. An example data return here is: {"question":{ "question_id":"19", "question_text":"testing", "other_crap":"none" }, "timestamp":{ "response":"answer", "response_text":"the text here" } } I am completely at a loss. Hopefully someone has some insight into what's going on...thank you!

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  • Rails Association issue with NoMethodError in event_controller

    - by pmanning
    Kinda a noob trying to understand I think I need to define rsvps but not sure what to put... I'm trying to add a Join/Unjoin button to user created Events, similar to a Follow/Unfollow button for Users. NoMethodError in Events#show undefined method `model_name' for NilClass:Class in line #1 _unjoin.html.erb 1: <%= form_for(current_user.rsvps.find_by_joined_id(@event), 2: html: { method: :delete }) do |f| %> 3: <%= f.submit "Leave", class: "btn btn-large" %> 4: <% end %> events_controller.rb def show @event = Event.find(params[:id]) @user = current_user end Here's the models rsvp.rb class Rsvp < ActiveRecord::Base attr_accessible :joined_id belongs_to :joiner, class_name: "User" belongs_to :joined, class_name: "User" validates :joiner_id, presence: true validates :joined_id, presence: true end user.rb has_many :rsvps, foreign_key: "joiner_id", dependent: :destroy has_many :joined_events, through: :rsvps, source: :joined has_many :reverse_rsvps, foreign_key: "joined_id", class_name: "Rsvp", dependent: :destroy has_many :joiners, through: :reverse_rsvps, source: :joiner event.rb belongs_to :user has_many :rsvps, foreign_key: "joiner_id", dependent: :destroy has_many :joined_events, through: :rsvps, source: :joined has_many :reverse_rsvps, foreign_key: "joined_id", class_name: "Rsvp", dependent: :destroy has_many :joiners, through: :reverse_rsvps, source: :joiner

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  • Context dependent validation

    - by Ole Lynge
    I would like to be able to validate an object in different contexts using DataAnnotations in .NET 4. For example: If I have a class with these annotated properties [Required] public string Name { get; set; } [Required] public string PhoneNumber { get; set; } [Required] public string Address { get; set; } I would like to be able to do something like bool namePhoneValid = Validator.TryValidateObject(entity, contextNamePhone, results1); bool allValid = Validator.TryValidateObject(entity, contextAll, results2); where contextNamePhone only validates Name and Phone, and contextAll validates all properties (Name, Phone and Address in this case). Is this possible? How should the validation context be constructed? Are there other/smarter ways to do this?

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  • Showing div based on filled form field

    - by Fabio
    I have this script where I use a slider to show some elements of a form. So far so good. The way I'm doing it is by having a slider (can't use a multistep form since it uses a plugin not allowing multistep forms, plus some graphic behaviors) and a button that goes to the next slider. So now I need that button (not part of the form) to show only if a certain field is filled. I tried teh following, but it's not working, I assume some error but can't figure what. My code is as follows: $('#clientname').change(function() { var clientVal = $("input").val() == ''; $(".next").hide(); if ($('#clientname').val() != '').show(); else $('.next').hide(); }); and the html as follows: <div class="b40-right"> <h3>The Basics</h3> <div class="label"> Your Name (required)</div> <div class="inputes"> <span class="wpcf7-form-control-wrap your-name"><input id="clientname" type="text" name="your-name" value="" class="wpcf7-form-control wpcf7-text wpcf7-validates-as-required" size="40" /></span> </div> <div class="label">Your Email (required)</div> <div class="inputes"> <span class="wpcf7-form-control-wrap your-email"><input type="text" name="your-email" value="" class="wpcf7-form-control wpcf7-text wpcf7-email wpcf7-validates-as-required wpcf7-validates-as-email" size="40" /></span> </div> <div class="label">Type of Business</div> <div class="inputes"> <span class="wpcf7-form-control-wrap type-of-business"><textarea name="type-of-business" class="wpcf7-form-control wpcf7-textarea" cols="40" rows="10"></textarea></span> </div> </div> <a class="next" href="javascript:stepcarousel.stepBy('mygallery2', 1)"><img id="nextbut1" src="<?php bloginfo('template_directory'); ?>/images/next.png" alt="" /></a> any help on what am I doing wrong? Is there a better approach/solution? (I'm not a programmer as you may figure) Thank you in advance!

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  • before_save not working with Rails 3

    - by Mich Dart
    I have this Project model: class Project < ActiveRecord::Base validates :status, :inclusion => { :in => ['active', 'closed'] } validates :title, :presence => true, :length => { :in => 4..30 } before_save :set_default_status_if_not_specified private def set_default_status_if_not_specified self.status = 'active' if self.status.blank? end end If I create a new object like this: Project.create!(:title => 'Test 2', :pm_id => 1) I get these errors: Validation failed: Status is not included in the list But status field should get filled in before save.

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  • SQL SERVER – Validating Spatial Object as NULL using IsNULL

    - by pinaldave
    Follow up questions are the most fun part of writing a blog post. Earlier I wrote about SQL SERVER – Validating Spatial Object with IsValidDetailed Function and today I received a follow up question on the same subject. The question was mainly about how NULL is handled by spatial functions. Well, NULL is NULL. It is very easy to work with NULL. There are two different ways to validate if the passed in the value is NULL or not. 1) Using IsNULL Function IsNULL function validates if the object is null or not, if object is not null it will return you value 0 and if object is NULL it will return you the value NULL. DECLARE @p GEOMETRY = 'Polygon((2 2, 3 3, 4 4, 5 5, 6 6, 2 2))' SELECT @p.ISNULL ObjIsNull GO DECLARE @p GEOMETRY = NULL SELECT @p.ISNULL ObjIsNull GO 2) Using IsValidDetailed Function IsValidateDetails function validates if the object is valid or not. If the object is valid it will return 24400: Valid but if the object is not valid it will give message with the error number. In case object is NULL it will return the value as NULL. DECLARE @p GEOMETRY = 'Polygon((2 2, 3 3, 4 4, 5 5, 6 6, 2 2))' SELECT @p.IsValidDetailed() IsValid GO DECLARE @p GEOMETRY = NULL SELECT @p.IsValidDetailed() IsValid GO When to use what? Now you can see that there are two different ways to validate the NULL values. I personally have no preference about using one over another. However, there is one clear difference between them. In case of the IsValidDetailed Function the return value is nvarchar(max) and it is not always possible to compare the value with nvarchar(max). Whereas the ISNULL function returns the bit value of 0 when the object is null and it is easy to determine if the object is null or not in the case of ISNULL function. Additionally, ISNULL function does not check if the object is valid or not and will return the value 0 if the object is not NULL. Now you know even though either of the function can be used in place of each other both have very specific use case. Use the one which fits your business case. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Function, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Spatial Database, SQL Spatial

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  • Identity Propagation across Web and Web Service - 11g

    - by Prakash Yamuna
    I was on a customer call recently and this topic came up. In fact since this topic seems to come up fairly frequently - I thought I would describe the recommended model for doing SSO for Web Apps and then doing Identity Propagation across the Back end web services. The Image below shows a typical flow: Here is a more detailed drill down of what happens at each step of the flow (the number in red in the diagram maps to the description below of the behind the scenes processing that happens in the stack). [1] The Web App is protected with OAM and so the typical SSO scenario is applicable. The Web App URL is protected in OAM. The Web Gate intercepts the request from the Browser to the Web App - if there is an OAM (SSO) token - then the Web Gate validates the OAM token. If there is no SSO token - then the user is directed to the login page - user enters credentials, user is authenticated and OAM token is created for that browser session. [2] Once the Web Gate validates the OAM token - the token is propagated to the WLS Server where the Web App is running. You need to ensure that you have configured the OAM Identity Asserter in the Weblogic domain. If the OAM Identity Asserter is configured, this will end up creating a JAAS Subject. Details can be found at: http://docs.oracle.com/cd/E23943_01/doc.1111/e15478/webgate.htm#CACIAEDJ [3] The Web Service client (in the Web App) is secured with one of the OWSM SAML Client Policies. If secured in this fashion, the OWSM Agent creates a SAML Token from the JAAS Subject (created in [2] by the OAM Identity Asserter) and injects it into the SOAP message. Steps for securing a JEE JAX-WS Proxy Client using OWSM Policies are documented at: http://docs.oracle.com/cd/E23943_01/web.1111/b32511/attaching.htm#BABBHHHC Note: As shown in the diagram - instead of building a JEE Web App - you can also use WebCenter and build portlets. If you are using WebCenter then you can follow the same architecture. Only the steps for securing WebCenter Portlets with OWSM is different. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} http://docs.oracle.com/cd/E23943_01/webcenter.1111/e12405/wcadm_security_wss.htm#CIHEBAHB [4] The SOA Composite App is secured with OWSM SAML Service policy. OWSM Agent intercepts the incoming SOAP request and validates the SAML token and creates a JAAS Subject. [5] When the SOA Composite App tries to invoke the OSB Proxy Service, the SOA Composite App "Reference" is secured with OWSM SAML Client Policy. Here again OWSM Agent will create a new SAML Token from the JAAS Subject created in [4] by the OWSM Agent and inject it into the SOAP message. Steps for securing SOA Composite Apps (Service, Reference, Component) are documented at: Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} http://docs.oracle.com/cd/E23943_01/web.1111/b32511/attaching.htm#CEGDGIHD [6] When the request reaches the OSB Proxy Service, the Proxy Service is again secured with the OWSM SAML Token Service Policy. So the same steps are performed as in [4]. The end result is a JAAS Subject. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} [7] When OSB needs to invoke the Business App Web Service, it goes through the OSB Business Service. The OSB Business Service is secured with OWSM SAML Client Policy and step [5] is repeated. Steps for securing OSB Proxy Service and OSB Business Services are document at: http://docs.oracle.com/cd/E23943_01/admin.1111/e15867/proxy_services.htm#OSBAG1097[8] Finally when the message reaches the Business App Web Service, this service is protected by OWSM SAML Service policy and step [4] is repeated by the OWSM Agent. Steps for securing Weblogic Web Services, ADF Web Services, etc are documented at: http://docs.oracle.com/cd/E23943_01/web.1111/b32511/attaching.htm#CEGCJDIF In the above description for purposes of brevity - I have not described which OWSM SAML policies one should use; OWSM ships with a number of SAML policies, I briefly described some of the trade-offs involved with the various SAML policies here. The diagram above and the accompanying description of what is happening in each step of the flow - assumes you are using "SAML SV" or SAML Bearer" based policies without an STS.

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  • Unit test: How best to provide an XML input?

    - by TheSilverBullet
    I need to write a unit test which validates the serialization of two attributes of an XML(size ~ 30 KB) file. What is the best way to provide an input for this test? Here are the options I have considered: Add the file to the project and use a file reader Pass the contents of the XML as a string Create the XML through a program and pass it Which is my best option and why? If there is another way which you think is better, I would love to hear it.

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  • Licensing generator/validator program [closed]

    - by AtoMerZ
    I need to write a program that generates/validates license for users of my application. The application has a number of features each of which can be purchased by the user. Also each feature can be enabled in trial mode. Meaning only for a specified duration of time. Before I actually try to write the code myself, I'm wondering if there are any free/commercial programs similar to what I'm looking for.

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  • google analytics statistics

    - by colmcq
    I am compiling a report for a client using google analytics. I have observed that the client has unusually good page view times (5 mins) and excellent bounce rates (<25%). I need to reference research data that validates my assertion that these figures are excellent compared to an industry standard (the industry is ecommerce and gaming). Can you direct me to any published research data that specifies normal bounce rates and page view times for this industry?

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  • sharing message object between web applications

    - by jezhilvalan
    I need to share java mail message objects between two web applications(A and B). WebApplication A obtains the message and write it to the outputStream for(int i=0;i<messagesArr.length;i++){ uid = pop3FolderObj.getUID(messagesArr[i]); //storing messages with uid names inorder to maintain uniqueness File f = new File("F:/PersistedMessagesFolder" + uid); FileOutputStream fos = new FileOutputStream(f); messagesArr[i].writeTo(fos); fos.flush(); fos.close(); } Is FileOutputStream the best output stream for persisting message objects? Is it possible to use ObjectOutputStream for message object persistence? WebApplication B reads the message object via InputStream FileInputStream fis = new FileInputStream("F:/MessagesPersistedFolder"+uid); MimeMessage mm = new MimeMessage(sessionObj,fis); What if the mail message object which is already written via WebApplication A is not a MimeMessage? How can I read non-mime messages using input stream? MimeMessage constructor mandates sessionObj as the first parameter? How can I obtain this sessionObj in WebApplicationB? Do I have to again establish store connection with the same emailid,emailpassword,popserver and port(already used in WebApplication A) with the email server inorder to obtain this session object? Even if obtained, will this session object remains the same as that of the session object which is priorly obtained in WebApplicationA? Since I am using uids to name Message objects (inorder to maintain uniqueness of file names) how can I share these uids between WebApplication A and WebApplication B? WebApplication B needs the uid inorder to access the specific file which is present in "F:/MessagesPersistedFolder" Please help me in resolving the aforeseen issues.

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  • Uniquing with Existing Core Data Entities

    - by warrenm
    I'm using Core Data to store a lot (1000s) of items. A pair of properties on each item are used to determine uniqueness, so when a new item comes in, I compare it against the existing items before inserting it. Since the incoming data is in the form of an RSS feed, there are often many duplicates, and the cost of the uniquing step is O(N^2), which has become significant. Right now, I create a set of existing items before iterating over the list of (possible) new items. My theory is that on the first iteration, all the items will be faulted in, and assuming we aren't pressed for memory, most of those items will remain resident over the course of the iteration. I see my options thusly: Use string comparison for uniquing, iterating over all "new" items and comparing to all existing items (Current approach) Use a predicate to filter the set of existing items against the properties of the "new" items. Use a predicate with Core Data to determine uniqueness of each "new" item (without retrieving the set of existing items). Is option 3 likely to be faster than my current approach? Do you know of a better way?

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  • Spring Data Neo4J @Indexed(unique = true) not working

    - by Markus Lamm
    I'm new to Neo4J and I have, probably an easy question. There're NodeEntitys in my application, a property (name) is annotated with @Indexed(unique = true) to achieve the uniqueness like I do in JPA with @Column(unique = true). My problem is, that when I persist an entity with a name that already exists in my graph, it works fine anyway. But I expected some kind of exception here...?! Here' s an overview over basic my code: @NodeEntity public abstract class BaseEntity implements Identifiable { @GraphId private Long entityId; ... } public class Role extends BaseEntity { @Indexed(unique = true) private String name; ... } public interface RoleRepository extends GraphRepository<Role> { Role findByName(String name); } @Service public class RoleServiceImpl extends BaseEntityServiceImpl<Role> implements { private RoleRepository repository; @Override @Transactional public T save(final T entity) { return getRepository().save(entity); } } And this is my test: @Test public void testNameUniqueIndex() { final List<Role> roles = Lists.newLinkedList(service.findAll()); final String existingName = roles.get(0).getName(); Role newRole = new Role.Builder(existingName).build(); newRole = service.save(newRole); } That's the point where I expect something to go wrong! How can I ensure the uniqueness of a property, without checking it for myself?? THANKS IN ADVANCE FOR ANY IDEAS!! P.S.: I'm using neo4j 1.8.M07, spring-data-neo4j 2.1.0.BUILD-SNAPSHOT and Spring 3.1.2.RELEASE.

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  • Beware Sneaky Reads with Unique Indexes

    - by Paul White NZ
    A few days ago, Sandra Mueller (twitter | blog) asked a question using twitter’s #sqlhelp hash tag: “Might SQL Server retrieve (out-of-row) LOB data from a table, even if the column isn’t referenced in the query?” Leaving aside trivial cases (like selecting a computed column that does reference the LOB data), one might be tempted to say that no, SQL Server does not read data you haven’t asked for.  In general, that’s quite correct; however there are cases where SQL Server might sneakily retrieve a LOB column… Example Table Here’s a T-SQL script to create that table and populate it with 1,000 rows: CREATE TABLE dbo.LOBtest ( pk INTEGER IDENTITY NOT NULL, some_value INTEGER NULL, lob_data VARCHAR(MAX) NULL, another_column CHAR(5) NULL, CONSTRAINT [PK dbo.LOBtest pk] PRIMARY KEY CLUSTERED (pk ASC) ); GO DECLARE @Data VARCHAR(MAX); SET @Data = REPLICATE(CONVERT(VARCHAR(MAX), 'x'), 65540);   WITH Numbers (n) AS ( SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) FROM master.sys.columns C1, master.sys.columns C2 ) INSERT LOBtest WITH (TABLOCKX) ( some_value, lob_data ) SELECT TOP (1000) N.n, @Data FROM Numbers N WHERE N.n <= 1000; Test 1: A Simple Update Let’s run a query to subtract one from every value in the some_value column: UPDATE dbo.LOBtest WITH (TABLOCKX) SET some_value = some_value - 1; As you might expect, modifying this integer column in 1,000 rows doesn’t take very long, or use many resources.  The STATITICS IO and TIME output shows a total of 9 logical reads, and 25ms elapsed time.  The query plan is also very simple: Looking at the Clustered Index Scan, we can see that SQL Server only retrieves the pk and some_value columns during the scan: The pk column is needed by the Clustered Index Update operator to uniquely identify the row that is being changed.  The some_value column is used by the Compute Scalar to calculate the new value.  (In case you are wondering what the Top operator is for, it is used to enforce SET ROWCOUNT). Test 2: Simple Update with an Index Now let’s create a nonclustered index keyed on the some_value column, with lob_data as an included column: CREATE NONCLUSTERED INDEX [IX dbo.LOBtest some_value (lob_data)] ON dbo.LOBtest (some_value) INCLUDE ( lob_data ) WITH ( FILLFACTOR = 100, MAXDOP = 1, SORT_IN_TEMPDB = ON ); This is not a useful index for our simple update query; imagine that someone else created it for a different purpose.  Let’s run our update query again: UPDATE dbo.LOBtest WITH (TABLOCKX) SET some_value = some_value - 1; We find that it now requires 4,014 logical reads and the elapsed query time has increased to around 100ms.  The extra logical reads (4 per row) are an expected consequence of maintaining the nonclustered index. The query plan is very similar to before (click to enlarge): The Clustered Index Update operator picks up the extra work of maintaining the nonclustered index. The new Compute Scalar operators detect whether the value in the some_value column has actually been changed by the update.  SQL Server may be able to skip maintaining the nonclustered index if the value hasn’t changed (see my previous post on non-updating updates for details).  Our simple query does change the value of some_data in every row, so this optimization doesn’t add any value in this specific case. The output list of columns from the Clustered Index Scan hasn’t changed from the one shown previously: SQL Server still just reads the pk and some_data columns.  Cool. Overall then, adding the nonclustered index hasn’t had any startling effects, and the LOB column data still isn’t being read from the table.  Let’s see what happens if we make the nonclustered index unique. Test 3: Simple Update with a Unique Index Here’s the script to create a new unique index, and drop the old one: CREATE UNIQUE NONCLUSTERED INDEX [UQ dbo.LOBtest some_value (lob_data)] ON dbo.LOBtest (some_value) INCLUDE ( lob_data ) WITH ( FILLFACTOR = 100, MAXDOP = 1, SORT_IN_TEMPDB = ON ); GO DROP INDEX [IX dbo.LOBtest some_value (lob_data)] ON dbo.LOBtest; Remember that SQL Server only enforces uniqueness on index keys (the some_data column).  The lob_data column is simply stored at the leaf-level of the non-clustered index.  With that in mind, we might expect this change to make very little difference.  Let’s see: UPDATE dbo.LOBtest WITH (TABLOCKX) SET some_value = some_value - 1; Whoa!  Now look at the elapsed time and logical reads: Scan count 1, logical reads 2016, physical reads 0, read-ahead reads 0, lob logical reads 36015, lob physical reads 0, lob read-ahead reads 15992.   CPU time = 172 ms, elapsed time = 16172 ms. Even with all the data and index pages in memory, the query took over 16 seconds to update just 1,000 rows, performing over 52,000 LOB logical reads (nearly 16,000 of those using read-ahead). Why on earth is SQL Server reading LOB data in a query that only updates a single integer column? The Query Plan The query plan for test 3 looks a bit more complex than before: In fact, the bottom level is exactly the same as we saw with the non-unique index.  The top level has heaps of new stuff though, which I’ll come to in a moment. You might be expecting to find that the Clustered Index Scan is now reading the lob_data column (for some reason).  After all, we need to explain where all the LOB logical reads are coming from.  Sadly, when we look at the properties of the Clustered Index Scan, we see exactly the same as before: SQL Server is still only reading the pk and some_value columns – so what’s doing the LOB reads? Updates that Sneakily Read Data We have to go as far as the Clustered Index Update operator before we see LOB data in the output list: [Expr1020] is a bit flag added by an earlier Compute Scalar.  It is set true if the some_value column has not been changed (part of the non-updating updates optimization I mentioned earlier). The Clustered Index Update operator adds two new columns: the lob_data column, and some_value_OLD.  The some_value_OLD column, as the name suggests, is the pre-update value of the some_value column.  At this point, the clustered index has already been updated with the new value, but we haven’t touched the nonclustered index yet. An interesting observation here is that the Clustered Index Update operator can read a column into the data flow as part of its update operation.  SQL Server could have read the LOB data as part of the initial Clustered Index Scan, but that would mean carrying the data through all the operations that occur prior to the Clustered Index Update.  The server knows it will have to go back to the clustered index row to update it, so it delays reading the LOB data until then.  Sneaky! Why the LOB Data Is Needed This is all very interesting (I hope), but why is SQL Server reading the LOB data?  For that matter, why does it need to pass the pre-update value of the some_value column out of the Clustered Index Update? The answer relates to the top row of the query plan for test 3.  I’ll reproduce it here for convenience: Notice that this is a wide (per-index) update plan.  SQL Server used a narrow (per-row) update plan in test 2, where the Clustered Index Update took care of maintaining the nonclustered index too.  I’ll talk more about this difference shortly. The Split/Sort/Collapse combination is an optimization, which aims to make per-index update plans more efficient.  It does this by breaking each update into a delete/insert pair, reordering the operations, removing any redundant operations, and finally applying the net effect of all the changes to the nonclustered index. Imagine we had a unique index which currently holds three rows with the values 1, 2, and 3.  If we run a query that adds 1 to each row value, we would end up with values 2, 3, and 4.  The net effect of all the changes is the same as if we simply deleted the value 1, and added a new value 4. By applying net changes, SQL Server can also avoid false unique-key violations.  If we tried to immediately update the value 1 to a 2, it would conflict with the existing value 2 (which would soon be updated to 3 of course) and the query would fail.  You might argue that SQL Server could avoid the uniqueness violation by starting with the highest value (3) and working down.  That’s fine, but it’s not possible to generalize this logic to work with every possible update query. SQL Server has to use a wide update plan if it sees any risk of false uniqueness violations.  It’s worth noting that the logic SQL Server uses to detect whether these violations are possible has definite limits.  As a result, you will often receive a wide update plan, even when you can see that no violations are possible. Another benefit of this optimization is that it includes a sort on the index key as part of its work.  Processing the index changes in index key order promotes sequential I/O against the nonclustered index. A side-effect of all this is that the net changes might include one or more inserts.  In order to insert a new row in the index, SQL Server obviously needs all the columns – the key column and the included LOB column.  This is the reason SQL Server reads the LOB data as part of the Clustered Index Update. In addition, the some_value_OLD column is required by the Split operator (it turns updates into delete/insert pairs).  In order to generate the correct index key delete operation, it needs the old key value. The irony is that in this case the Split/Sort/Collapse optimization is anything but.  Reading all that LOB data is extremely expensive, so it is sad that the current version of SQL Server has no way to avoid it. Finally, for completeness, I should mention that the Filter operator is there to filter out the non-updating updates. Beating the Set-Based Update with a Cursor One situation where SQL Server can see that false unique-key violations aren’t possible is where it can guarantee that only one row is being updated.  Armed with this knowledge, we can write a cursor (or the WHILE-loop equivalent) that updates one row at a time, and so avoids reading the LOB data: SET NOCOUNT ON; SET STATISTICS XML, IO, TIME OFF;   DECLARE @PK INTEGER, @StartTime DATETIME; SET @StartTime = GETUTCDATE();   DECLARE curUpdate CURSOR LOCAL FORWARD_ONLY KEYSET SCROLL_LOCKS FOR SELECT L.pk FROM LOBtest L ORDER BY L.pk ASC;   OPEN curUpdate;   WHILE (1 = 1) BEGIN FETCH NEXT FROM curUpdate INTO @PK;   IF @@FETCH_STATUS = -1 BREAK; IF @@FETCH_STATUS = -2 CONTINUE;   UPDATE dbo.LOBtest SET some_value = some_value - 1 WHERE CURRENT OF curUpdate; END;   CLOSE curUpdate; DEALLOCATE curUpdate;   SELECT DATEDIFF(MILLISECOND, @StartTime, GETUTCDATE()); That completes the update in 1280 milliseconds (remember test 3 took over 16 seconds!) I used the WHERE CURRENT OF syntax there and a KEYSET cursor, just for the fun of it.  One could just as well use a WHERE clause that specified the primary key value instead. Clustered Indexes A clustered index is the ultimate index with included columns: all non-key columns are included columns in a clustered index.  Let’s re-create the test table and data with an updatable primary key, and without any non-clustered indexes: IF OBJECT_ID(N'dbo.LOBtest', N'U') IS NOT NULL DROP TABLE dbo.LOBtest; GO CREATE TABLE dbo.LOBtest ( pk INTEGER NOT NULL, some_value INTEGER NULL, lob_data VARCHAR(MAX) NULL, another_column CHAR(5) NULL, CONSTRAINT [PK dbo.LOBtest pk] PRIMARY KEY CLUSTERED (pk ASC) ); GO DECLARE @Data VARCHAR(MAX); SET @Data = REPLICATE(CONVERT(VARCHAR(MAX), 'x'), 65540);   WITH Numbers (n) AS ( SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) FROM master.sys.columns C1, master.sys.columns C2 ) INSERT LOBtest WITH (TABLOCKX) ( pk, some_value, lob_data ) SELECT TOP (1000) N.n, N.n, @Data FROM Numbers N WHERE N.n <= 1000; Now here’s a query to modify the cluster keys: UPDATE dbo.LOBtest SET pk = pk + 1; The query plan is: As you can see, the Split/Sort/Collapse optimization is present, and we also gain an Eager Table Spool, for Halloween protection.  In addition, SQL Server now has no choice but to read the LOB data in the Clustered Index Scan: The performance is not great, as you might expect (even though there is no non-clustered index to maintain): Table 'LOBtest'. Scan count 1, logical reads 2011, physical reads 0, read-ahead reads 0, lob logical reads 36015, lob physical reads 0, lob read-ahead reads 15992.   Table 'Worktable'. Scan count 1, logical reads 2040, physical reads 0, read-ahead reads 0, lob logical reads 34000, lob physical reads 0, lob read-ahead reads 8000.   SQL Server Execution Times: CPU time = 483 ms, elapsed time = 17884 ms. Notice how the LOB data is read twice: once from the Clustered Index Scan, and again from the work table in tempdb used by the Eager Spool. If you try the same test with a non-unique clustered index (rather than a primary key), you’ll get a much more efficient plan that just passes the cluster key (including uniqueifier) around (no LOB data or other non-key columns): A unique non-clustered index (on a heap) works well too: Both those queries complete in a few tens of milliseconds, with no LOB reads, and just a few thousand logical reads.  (In fact the heap is rather more efficient). There are lots more fun combinations to try that I don’t have space for here. Final Thoughts The behaviour shown in this post is not limited to LOB data by any means.  If the conditions are met, any unique index that has included columns can produce similar behaviour – something to bear in mind when adding large INCLUDE columns to achieve covering queries, perhaps. Paul White Email: [email protected] Twitter: @PaulWhiteNZ

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  • Federated access to desktop and network resources in MS AD domains

    - by Glenn Stauffer
    We are looking for a way to provide members of three loosely connected organizations with access to authenticated resources such as file shares, printers, and lab computers. I've seen federation facilities for web resources; is ther something similar for domain logins? Our Active directory domains are not connected so we would have to use email addresses for the username to insure uniqueness. Is there any openid like mechanism that works for AD logins?

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  • Is Form validation and Business validation too much?

    - by Robert Cabri
    I've got this question about form validation and business validation. I see a lot of frameworks that use some sort of form validation library. You submit some values and the library validates the values from the form. If not ok it will show some errors on you screen. If all goes to plan the values will be set into domain objects. Here the values will be or, better said, should validated (again). Most likely the same validation in the validation library. I know 2 PHP frameworks having this kind of construction Zend/Kohana. When I look at programming and some principles like Don't Repeat Yourself (DRY) and single responsibility principle (SRP) this isn't a good way. As you can see it validates twice. Why not create domain objects that do the actual validation. Example: Form with username and email form is submitted. Values of the username field and the email field will be populated in 2 different Domain objects: Username and Email class Username {} class Email {} These objects validate their data and if not valid throw an exception. Do you agree? What do you think about this aproach? Is there a better way to implement validations? I'm confused about a lot of frameworks/developers handling this stuff. Are they all wrong or am I missing a point? Edit: I know there should also be client side kind of validation. This is a different ballgame in my Opinion. If You have some comments on this and a way to deal with this kind of stuff, please provide.

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  • Swimlane Diagram Softwares with Expand/Collapse Features

    - by louis xie
    I've been searching real hard for a software which can fulfill my needs, but to no avail. I have a swimlane diagram which is extremely huge, and almost impossible to model using Visio or any traditional swimlane software. I would need to model both the operational process, as well as the interactions within an application and between different applications. Therefore, without wasting additional effort modelling these separately, I am looking for a solution which I can combine both views together. That is, possibly one which I can expand/collapse/group/ungroup processes/subprocesses together. Take a typical credit card process for instance, a hypothetical description of the swimlane could be as such: Customer submits application form to the bank Bank Officer A receives the application form and validates that it was correctly filled Bank Officer A submits application form to Bank Officer B for processing. Bank Officer B checks credit quality of the customer through Application X. Application X submits query to Application Y to retrieve Credit Report. Application X retrieves credit report and submits to Application Z for computation of credit scores Bank Officer B validates that customer is credit worthy, and submits application to Bank Officer C for processing. The above is an over-simplified credit card request process, and a purely hypothetical one. What I'm trying to drive at is, each of the above processes have sub-processes, and I want to be able to switch between a "detailed" view and "aggregated" view. If possible, add in time dependency of the different tasks, as well. I haven't been able to find one such software which could do this.

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  • Queuing using table or MSMQ?

    - by Lieven Cardoen
    A part of the application I'm working on is an swf that shows a test with some 80 questions. Each question is saved to a sql server through WebORB and asp.net. If a candidate finisheds the test, the session needs to be validated. Problem now is that sometimes 350 candidates finish their test at the same moment, and cpu on webserver and sql server explodes (350 validations concurrently). Now, how would I implement queuing here? In the database, there's a table that has a record for each session. One column holds the status. 1 is finished, 2 is validated. I could implement queuing in two ways (as I see it, maybe you have other propositions): A process that checks the table for records with status 1. If it finds one, it validates the session. So, sessions are validated one after one. If a candidate finishes its session, a message is sent to a MSMQ queue. Another process listens to the queue and validates sessions one after one. Now, What would be the best approach? Where do you start the process that will validate sessions? In your global.asax (application_start)? As a windows service? As an exe on the root of the website that is started in application_start? To me, using the table and looking for records with status 1 seems the easiest way.

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  • CodeIgniter - Image Validation & Thumbnailing

    - by Sebhael
    I'm currently trying to create a function that validates and creates thumbnails for images on upload - but I'm quite lost on what I'm doing. I'm assuming I'm off on my terminology so I'm not really getting any search results to help point me in the right direction. My playground is a form with 6 upload fields that are required. One of these fields is for a simple 32x32 icon image, another a portrait orientation (most likely) photo, and then 4 standard desktop screenshots -- and I'm using CodeIgniter as my framework. I would like to create a function that validates/thumbnails images, and only have to call it on the validation if at all possible. I know I can achieve this per-image, since the documentation for CI is quite through on this - but to reduce redundancy I'm looking for the better option. Outside of that, I don't even actually understand in full how to manipulate images unless it's just $this-input-post('field') - then calling all functions onto this? I don't know, I'm confused and posting on the actual CI forums has yielded me nothing - so all I'm really looking for is a point in the right direction to understanding what I'm trying to achieve here. This also all might not make any sense, I know it doesn't to me - but I can explain more if needed. Thanks in advance.

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  • Mixing has_one and has_and_belongs_to_many associations

    - by Thomas
    I'm trying to build a database of urls(links). I have a Category model that has and belongs to many Links. Here's the migration I ran: class CreateLinksCategories < ActiveRecord::Migration def self.up create_table :links_categories, :id => false do |t| t.references :link t.references :category end end def self.down drop_table :links_categories end end Here's the Link model: class Link < ActiveRecord::Base validates :path, :presence => true, :format => { :with => /^(#{URI::regexp(%w(http https))})$|^$/ } validates :name, :presence => true has_one :category end Here's the category model: class Category < ActiveRecord::Base has_and_belongs_to_many :links end And here's the error the console kicked back when I tried to associate the first link with the first category: >>link = Link.first => #<Link id: 1, path: "http://www.yahoo.com", created_at: "2011-01-10... >>category = Category.first => #<category id : 1, name: "News Site", created_at: "2011-01-11... >>link.category << category => ActiveRecord::StatementInvalid: SQLite3::Exception: no such column : categories.link_id: Are my associations wrong or am I missing something in the database? I expected it to find the links_categories table. Any help is appreciated.

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  • Rails dealing with blank params at controller level

    - by stephenmurdoch
    I have a User model: class User < ActiveRecord::Base has_secure_password # validation lets users update accounts without entering password validates :password, presence: { on: :create }, allow_blank: { on: :update } validates :password_confirmation, presence: { if: :password_digest_changed? } end I also have a password_reset_controller: def update # this is emailed to the user by the create action - not shown @user=User.find_by_password_reset_token!(params[:id]) if @user.update_attributes(params[:user]) # user is signed in if password and confirmation pass validations sign_in @user redirect_to root_url, :notice => "Password has been reset." else flash.now[:error] = "Something went wrong, please try again." render :edit end end Can you see the problem here? A user can submit a blank a password/confirmation and rails will sign them in, because the User model allows blank on update. It's not a security concern, since an attacker would still need access to a user's email account before they could get anywhere near this action, but my problem is that a user submitting 6 blank chars would be signed in, and their password would not be changed for them, which could lead to confusion later on. So, I've come up with the following solution, and I'd like to check if there's a better way of doing it, before I push to production: def update @user=User.find_by_password_reset_token!(params[:id]) # if user submits blank password, add an error, and render edit action if params[:user][:password].blank? @user.errors.add(:password_digest, "can't be blank.") render :edit elsif @user.update_attributes(params[:user]) sign_in @user redirect_to root_url, :notice => "Password has been reset." else flash.now[:error] = "Something went wrong, please try again." render :edit end end Should I be checking for nil as well as blank? Are there any rails patterns or idiomatic ruby techniques for solving this? [Fwiw, I've got required: true on the html inputs, but want this handled server side too.]

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  • Rails how to return a list of answers with a specific question_id

    - by mytwocentsisworthtwocents
    Let's say I have two Models, Answers and Questions (there are others, but irrelevant to the question). The models are as follows: Answer.rb class Answer < ActiveRecord::Base attr_accessible :description, :question_id has_one :question, :through => :user, :dependent => :destroy validates :description, :presence => true end Question.rb class Question < ActiveRecord::Base attr_accessible :budget, :description, :headline, :user_id, :updated_at, :created_at belongs_to :user has_many :answers validates :headline, :description, :user_id, :presence => true end I'd like to display on a page a list of all answers associated with a question, and only those questions. I got this far. I believe this variable finds all the questions in the database by the question_id (foreign key): @findanswers = Answer.all(params[:question_id]) And this one grabs the the id of the current question (this code will reside as an ERB on the page where the current question is located): @questionshow = Question.find(params[:id]) And now I'm stuck. How do I put the two together so that I list all the answers with the current question id?

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