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• Getting Started with Fluent NHibernate

  - by Andy

  I'm trying to get into using Fluent NHibernate, and I have a couple questions. I'm finding the documentation to be lacking. I understand that Fluent NHibernate / NHibernate allows you to auto-generate a database schema. Do people usually only do this for Test/Dev databases? Or is that OK to do for a production database? If it's ok for production, how do you make sure that you're not blowing away production data every time you run your app? Once the database schema is already created, and you have production data, when new tables/columns/etc. need to be added to the Test and/or Production database, do people allow NHibernate to do this, or should this be done manually? Is there any REALLY GOOD documentation on Fluent NHibernate? (Please don't point me to the wiki because in following along with the "Your first project" code building it myself, I was getting run-time errors because they forget to tell you to add a reference. Not cool.) Thanks, Andy

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• dropdown list box to display in the row..

  - by kumar

  Please can any body tell me is this right what I am doing here.. I need to display a dropdown list box in each row in the grid var lastsel2; $("#table1").jqGrid({ scroll: 1, sortable: true, url: '/friends/names/shiva', datatype: "json", mtype: 'GET', height: 200, autowidth: false, pager: '#page', colNames: [//columns names here ], colModel: [ { name: 'A', index: '', width: 90 }, { name: 'B', index: '', width: 100 }, { name: 'C', index: '', width: 70 }, { name: 'D', index: '', width: 65}, { name: 'E', index: '', width: 105}, { name: 'F', index: '', width: 105 }, { name: 'G', index: '', width: 100 }, { name: 'H', index: '', width: 70}, { name: 'I', index: '', width: 60}, { name: 'J', index: '', width: 60}, { name: 'K', index: '', width: 40 }, { name: 'L', index: '', width: 70}, { name: 'M', index: '', width: 60 }, { name: 'N', index: '', edittype: 'select',editype:true, width: 100, editoptions: { value: { 1: 'AA', 2: 'CC',3:'BD''}} } ], onSelectRow: function(Acct_Code) { if (A&& A !== lastsel2) { $('#table1').restoreRow(lastsel2); $('#table1').editRow(A, true); lastsel2 = A; } }, Here i am not able to see the dropdown box in row click? Thanks

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• Another dynamic memory allocation bug.

  - by m4design

  I'm trying to allocate memory for a multidimensional array (8 rows, 3 columns). Here's the code for the allocation (I'm sure the error is clear for you) char **ptr = (char **) malloc( sizeof(char) * 8); for (i = 0; i < 3; i++) ptr[i] = (char *) malloc( sizeof(char) * 3); The crash happens when I reference this: ptr[3][0]; Unhandled exception at 0x0135144d in xxxx.exe: 0xC0000005: Access violation writing location 0xabababab. Are there any recommended references/readings for this kind of subject? Thanks.

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• Get current updated column name to use in a trigger

  - by Serge

  Is there a way to actually get the column name that was updated in order to use it in a trigger? Basically I'm trying to have an audit trail whenever a user inserts or updates a table (in this case it has to do with a Contact table) CREATE TRIGGER `after_update_contact` AFTER UPDATE ON `contact` FOR EACH ROW BEGIN INSERT INTO user_audit (id_user, even_date, table_name, record_id, field_name, old_value, new_value) VALUES (NEW.updatedby, NEW.lastUpdate, 'contact', NEW.id_contact, [...]) END How can I get the name of the column that's been updated and from that get the OLD and NEW values of that column. If multiple columns have been updated in a row or even multiple rows would it be possible to have an audit for each update?

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• JTable - Getting a cell into Edit mode on pressing Tab

  - by Luhar

  This is possibly has a trivial solution, but I am at the end of my tether so I hope somebody can help out. I use a JTable which has a custom renderer and a custom editor for a set of columns. The renderer uses a JLabel component and the editor uses a JSpinner component. Our users want to be able to enter values in a column, and then press TAB or ENTER to move to the next editable cell in the table. If I understand correctly, this is the default behaviour for a JTable. However, this doesn't seem to work correctly for me. Until the user clicks on the cell, only the JLabel is displayed. The JSpinner (i.e. CellEditor) is only displayed when a user double clicks on the cell. So, it looks like the cell is going into "edit" mode only on MouseEvents, but not when it has focus. How do I get the cell to go into edit mode as soon as it has focus?

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• Are UTF16 (as used by for example wide-winapi functions) characters always 2 byte long?

  - by Cray

  Please clarify for me, how does UTF16 work? I am a little confused, considering these points: There is a static type in C++, WCHAR, which is 2 bytes long. (always 2 bytes long obvisouly) Most of msdn and some other documentation seem to have the assumptions that the characters are always 2 bytes long. This can just be my imagination, I can't come up with any particular examples, but it just seems that way. There are no "extra wide" functions or characters types widely used in C++ or windows, so I would assume that UTF16 is all that is ever needed. To my uncertain knowledge, unicode has a lot more characters than 65535, so they obvisouly don't have enough space in 2 bytes. UTF16 seems to be a bigger version of UTF8, and UTF8 characters can be of different lengths. So if a UTF16 character not always 2 bytes long, how long else could it be? 3 bytes? or only multiples of 2? And then for example if there is a winapi function that wants to know the size of a wide string in characters, and the string contains 2 characters which are each 4 bytes long, how is the size of that string in characters calculated? Is it 2 chars long or 4 chars long? (since it is 8 bytes long, and each WCHAR is 2 bytes)

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• Copying Data between table without identity column

  - by user668479

  I have two table and I need to copy the data across from SRCServiceUsers to Clients Everytime i run it I get the following: Violation of PRIMARY KEY constraint 'PK_Clients'. Cannot insert duplicate key in object 'dbo.Clients'. The statement has been terminated. The Primary key ClientId field is not an identity column and therefore requires filling To date I have the following insert into Clients( ClientID, Title, Forenames, FamilyName, [Address], Town, County, PostCode, PhoneNumber, StartDate) SELECT ( Select Max(Clients.ClientID)+ 1, SRCServiceUsers.Title, SRCServiceUsers.[First Names], SRCServiceUsers.Surname, --BUILD UP MUITIPLE COLUMNS SRCServiceUsers.[Property Name] + ', ' + SRCServiceUsers.Street + ', ' + SRCServiceUsers.Suburb as [Address], SRCServiceUsers.Town, SRCServiceUsers.County, SRCServiceUsers.Postcode, SRCServiceUsers.Telephone, SRCServiceUsers.[Start Date] From srcsERVICEuSERS How can i autoincrement the PK field - CLientID when inserting the data? Many thanks Andrew

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• Interesting LinqToSql behaviour

  - by Ben Robinson

  We have a database table that stores the location of some wave files plus related meta data. There is a foreign key (employeeid) on the table that links to an employee table. However not all wav files relate to an employee, for these records employeeid is null. We are using LinqToSQl to access the database, the query to pull out all non employee related wav file records is as follows: var results = from Wavs in db.WaveFiles where Wavs.employeeid == null; Except this returns no records, despite the fact that there are records where employeeid is null. On profiling sql server i discovered the reason no records are returned is because LinqToSQl is turning it into SQL that looks very much like: SELECT Field1, Field2 //etc FROM WaveFiles WHERE 1=0 Obviously this returns no rows. However if I go into the DBML designer and remove the association and save. All of a sudden the exact same LINQ query turns into SELECT Field1, Field2 //etc FROM WaveFiles WHERE EmployeeID IS NULL I.e. if there is an association then LinqToSql assumes that all records have a value for the foreign key (even though it is nullable and the property appears as a nullable int on the WaveFile entity) and as such deliverately constructs a where clause that will return no records. Does anyone know if there is a way to keep the association in LinqToSQL but stop this behaviour. A workaround i can think of quickly is to have a calculated field called IsSystemFile and set it to 1 if employeeid is null and 0 otherwise. However this seems like a bit of a hack to work around strange behaviour of LinqToSQl and i would rather do something in the DBML file or define something on the foreign key constraint that will prevent this behaviour.

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• Lookup Field as a Site Column via CAML

  - by Rob Windsor

  I'm trying to create a Lookup Field as a Site Column via CAML. The list I want to use as the source of the lookup is created in the Feature Receiver so I don't know it's ID. I've read several blog posts that indicate that I can just put the path to the list in the List attribute. It seems from the comments on these post that this solution works for some people but not for others. I'm in the latter group. When I try to associate a content type that uses the lookup site column I: "Exception from HRESULT: 0x80040E07" <Field ID="{da94e56b-428f-4b95-b4c6-24aed0256475}" Name="Test_x0020_Lookup_x0020_Column" StaticName="Test_x0020_Lookup_x0020_Column" DisplayName="Test Lookup Column" Type="Lookup" Required="FALSE" List="Lists/Test" ShowField="Title" PrependId="TRUE" Group="Test Site Columns" /> <ContentType ID="0x0100B6D92594DDCE8E479D0EB0C414C463B0" Name="Test Lookup Content Type" Version="0" Group="Test Content Types"> <FieldRefs> <FieldRef ID="{da94e56b-428f-4b95-b4c6-24aed0256475}" Name="Test_x0020_Lookup_x0020_Column" Required="TRUE" /> </FieldRefs> </ContentType>

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• InvalidOperationException sequence contains more than one element even when only one element

  - by user310256

  I have three tables, tblCompany table, tblParts table and a link table between them tblLinkCompanyParts. Since tblLinkCompanyParts is a link table so the columns that it has are LinkCompanyPartID(primary key), CompanyID from tblCompany table and PartID from tblParts as foreign keys. I have tied them up in the dbml file. In code if I write LinkCompanyParts.Parts (where LinkCompanyParts is an object of the tblLinkCompanyParts type) to get to the corresponding Part object I get the "InvalidOperationException: Sequence constains more than one element". I have looked at the data in the database and there is only one Parts record associated with the LinkCompanyPartID. The stack trace reads like at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source) at System.Data.Linq.EntityRef`1.get_Entity() at ... I read about SingleOrDefault vs FirstOrDefault but since the link table should have a one-one mapping therefore I think SingleOrDefault should work and besides "SingleOrDefault" statement is being generated behind the scenes in the designer.cs file at the following line return this._Part.Entity; Any ideas?

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• Bind a WPF combobox and get selecteditem to a richtextbox

  - by Peter

  Hi, I am using a dataset on the server, in this dataset I have a datatable that calls a stored procedure and returns column names from three tables. I call this stored procedure using a web service. I manage to show all the column names in my combobox but when I want to click a button and insert selected column name into a richtextbox I get System.Data.DataRowView in the textbox instead. My code: 'the combobox 'if I don't have this textblock all the values are shown vertical instead of the normal horizontal lines 'the stored procedure SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE (TABLE_NAME = 'Customer') OR (TABLE_NAME = 'Invoices') OR (TABLE_NAME = 'Orders') 'the button Private Sub btnAddColumnNames_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles btnAddColumnNames.Click ' Add column names to the richtextbox Dim tr As New TextRange(rtbText.Selection.Start, rtbText.Selection.End) tr.Text = cboColumnNames.SelectedItem.ToString() rtbText.Focus() End Sub Any suggestions on how to get the selected text in the combobox to the richtextbox? Any help is appreciated.

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• ASP.NET Forms automation/serialization/binding

  - by creo

  I need to implement many forms in ASP.NET application (for IRS mostly). There are will be a lot of standard controls for each form (textboxes, dropdowns, checkboxes, radio). And business entity assigned to each. What's the best solution to automate this process? I need to: Have layout stored in DB (in XML). Layout must support several columns, tabbed interface Automatically bind business object values to the form Automatically read form values and write to business object Must support automatic validation Some basic workflows support would be good I used to work with TFS and saw how they implemented WorkItem templates (.wit files). In general this is all I need. But what framework did they build it on? How can I utilize this solution? I know about Dynamic Data only: http://www.asp.net/dynamicdata

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• How can I loop over a query for a specific number of times that may be greater than the result?

  - by JS

  I need to loop over a query exactly 12 times to complete rows in a form but rarely will the query return 12 rows. The cfquery endRow attribute doesn't force the loop to keep going if the result is < 12. If it did that would be ideal to use something like cfloop query="myQuery" endRow="12"... The 2 options that I have now are to skip the loop and write out all 12 rows but that results in a lot of duplicate code (there are 20 columns), or do a query of queries for each row which seems like a lot of wasted processing. Thanks for any ideas.

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• What does this structure actually do?

  - by LGTrader

  I found this structure code in a Julia Set example from a book on CUDA. I'm a newbie C programmer and cannot get my head around what it's doing, nor have I found the right thing to read on the web to clear it up. Here's the structure: struct cuComplex { float r; float i; cuComplex( float a, float b ) : r(a), i(b) {} float magnitude2( void ) { return r * r + i * i; } cuComplex operator*(const cuComplex& a) { return cuComplex(r*a.r - i*a.i, i*a.r + r*a.i); } cuComplex operator+(const cuComplex& a) { return cuComplex(r+a.r, i+a.i); } }; and it's called very simply like this: cuComplex c(-0.8, 0.156); cuComplex a(jx, jy); int i = 0; for (i=0; i<200; i++) { a = a * a + c; if (a.magnitude2() > 1000) return 0; } return 1; So, the code did what? Defined something of structure type 'cuComplex' giving the real and imaginary parts of a number. (-0.8 & 0.156) What is getting returned? (Or placed in the structure?) How do I work through the logic of the operator stuff in the struct to understand what is actually calculated and held there? I think that it's probably doing recursive calls back into the stucture float magnitude2 (void) { return return r * r + i * i; } probably calls the '*' operator for r and again for i, and then the results of those two operations call the '+' operator? Is this correct and what gets returned at each step? Just plain confused. Thanks!

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• GXT - link two components height

  - by jjczopek

  Hi! I want to have a panel, with two columns. The first column will contain a list of beans, and the right one a form panel for editing those beans. What I want to do, is that list height is the same as height of the form panel on the right. My list of beans will be larger and larger over time, so it's height will probably exceed form height. When that happens, there should be a scrollbar showed for the list. I also don't want to set explicit size for list and my form panel (it should be flexible because some time I will add or remove some form fields). I'm basically new to GXT. I'm looking forward for some proposals. Cheers, jjczopek

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• Creating a file upload template in Doctrine ORM

  - by balupton

  Hey all. I'm using Doctrine 1.2 as my ORM for a Zend Framework Project. I have defined the following Model for a File. File: columns: id: primary: true type: integer(4) unsigned: true code: type: string(255) unique: true notblank: true path: type: string(255) notblank: true size: type: integer(4) type: type: enum values: [file,document,image,video,audio,web,application,archive] default: unknown notnull: true mimetype: type: string(20) notnull: true width: type: integer(2) unsigned: true height: type: integer(2) unsigned: true Now here is the File Model php class (just skim through for now): <?php /** * File * * This class has been auto-generated by the Doctrine ORM Framework * * @package ##PACKAGE## * @subpackage ##SUBPACKAGE## * @author ##NAME## <##EMAIL##> * @version SVN: $Id: Builder.php 6365 2009-09-15 18:22:38Z jwage $ */ class File extends BaseFile { public function setUp ( ) { $this->hasMutator('file', 'setFile'); parent::setUp(); } public function setFile ( $file ) { global $Application; // Configuration $config = array(); $config['bal'] = $Application->getOption('bal'); // Check the file if ( !empty($file['error']) ) { $error = $file['error']; switch ( $file['error'] ) { case UPLOAD_ERR_INI_SIZE : $error = 'ini_size'; break; case UPLOAD_ERR_FORM_SIZE : $error = 'form_size'; break; case UPLOAD_ERR_PARTIAL : $error = 'partial'; break; case UPLOAD_ERR_NO_FILE : $error = 'no_file'; break; case UPLOAD_ERR_NO_TMP_DIR : $error = 'no_tmp_dir'; break; case UPLOAD_ERR_CANT_WRITE : $error = 'cant_write'; break; default : $error = 'unknown'; break; } throw new Doctrine_Exception('error-application-file-' . $error); return false; } if ( empty($file['tmp_name']) || !is_uploaded_file($file['tmp_name']) ) { throw new Doctrine_Exception('error-application-file-invalid'); return false; } // Prepare config $file_upload_path = realpath($config['bal']['files']['upload_path']) . DIRECTORY_SEPARATOR; // Prepare file $filename = $file['name']; $file_old_path = $file['tmp_name']; $file_new_path = $file_upload_path . $filename; $exist_attempt = 0; while ( file_exists($file_new_path) ) { // File already exists // Pump exist attempts ++$exist_attempt; // Add the attempt to the end of the file $file_new_path = $file_upload_path . get_filename($filename,false) . $exist_attempt . get_extension($filename); } // Move file $success = move_uploaded_file($file_old_path, $file_new_path); if ( !$success ) { throw new Doctrine_Exception('Unable to upload the file.'); return false; } // Secure $file_path = realpath($file_new_path); $file_size = filesize($file_path); $file_mimetype = get_mime_type($file_path); $file_type = get_filetype($file_path); // Apply $this->path = $file_path; $this->size = $file_size; $this->mimetype = $file_mimetype; $this->type = $file_type; // Apply: Image if ( $file_type === 'image' ) { $image_dimensions = image_dimensions($file_path); if ( !empty($image_dimensions) ) { // It is not a image we can modify $this->width = 0; $this->height = 0; } else { $this->width = $image_dimensions['width']; $this->height = $image_dimensions['height']; } } // Done return true; } /** * Download the File * @return */ public function download ( ) { global $Application; // File path $file_upload_path = realpath($config['bal']['files']['upload_path']) . DIRECTORY_SEPARATOR; $file_path = $file_upload_path . $this->file_path; // Output result and download become_file_download($file_path, null, null); die(); } public function postDelete ( $Event ) { global $Application; // Prepare $Invoker = $Event->getInvoker(); // Configuration $config = array(); $config['bal'] = $Application->getOption('bal'); // File path $file_upload_path = realpath($config['bal']['files']['upload_path']) . DIRECTORY_SEPARATOR; $file_path = $file_upload_path . $this->file_path; // Delete the file unlink($file_path); // Done return true; } } What I am hoping to accomplish is so that the above custom functionality within my model file can be turned into a validator, template, or something along the lines. So hopefully I can do something like: File: actAs: BalFile: columns: id: primary: true type: integer(4) unsigned: true code: type: string(255) unique: true notblank: true path: type: string(255) notblank: true size: type: integer(4) type: type: enum values: [file,document,image,video,audio,web,application,archive] default: unknown notnull: true mimetype: type: string(20) notnull: true width: type: integer(2) unsigned: true height: type: integer(2) unsigned: true I'm hoping for a validator so that say if I do $File->setFile($_FILE['uploaded_file']); It will provide a validation error, except in all the doctrine documentation it has little on custom validators, especially in the contect of "virtual" fields. So in summary, my question is: How earth can I go about making a template/extension to porting this functionality? I have tried before with templates but always gave up after a day :/ If you could take the time to port the above I would greatly appreciate it.

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• Idioms for a three-state toggle?

  - by Alex Mcp

  I have a table column where each row has one of three states, and the purpose of the row is to offer manipulation AND display of this property with three states. My current development view is to have three tightly packed radio buttons with labels at the head of the columns (and every 50 rows or so) and onClick they send an AJAX request and thar she blows. This is fugly. Is there a standard idiom for a control like this? I'm currently mocking up something similar to the iPhone on/off toggle, but with a "middle" state. Any input would be welcome.

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• SaaS Multi-tenancy Applications: How is data import/export/backup being implemented?

  - by Mark Redman

  How are applications providing import / export (or backups) of data in SaaS based multi-tenancy applications, particularly single database designs? Imports: Keeping things simple I think basic imports are useful, ie CSV to a spec (or a way of providing a mapping between CSV columns and fields in the database. Exports: In single database designs I have seen XML exports and HTML (basic sitse generated) exports of data? I would assume that XML is a better option? How does one cater for relational data? Would you reference various things within XML and provide documentation of the relationships or let users figurethis out? Are vendors providing an export/backup that can be imported back in/restored? Your comments appreciated.

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• How do I handle editing of custom types in a C# datagridview?

  - by Ian Hopkinson

  I have a datagridview in which one column contains a custom class, which I have set using: dgvPeriods.Columns[1].ValueType = typeof(ExDateTime); It is rigged up to display correctly by handling the CellFormatting event, but I'm unsure what event to handle for cell editing. In the absence of doing anything I get a FormatException as the datagridview tries to convert String to ExDateTime as I try to move focus out of the edited cell. I tried adding type conversion to my ExDateTime custom class: public static implicit operator ExDateTime(string b) { return new ExDateTime(b); } But this this didn't work. I also tried handling the DataError event, but this seems to fire too late. The datagridview is not databound.

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• How to access properties of Access Database Table using C# ADOX?

  - by Sachin G

  I have created MS Access Database using C# ADOX library. I have created one table with several columns. What I want to achieve is when I insert date in one column, the date format should be YYYY-MM-DD and not MM-DD-YYYY. I know its just display format, but I want to access the property which we set when we open access table in design mode, and for column with date data type, set format as Custom (YYYY-MM-DD). I want this to be set at runtime while creating table only. I wanted to know what should be property name that I should use in order to access and set the format property of column?

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• Is Jquery $(this) broken by jqgrid gridunload method?

  - by chohi

  I expect the following code to unload a javascipt jqgrid, then load another grid with different options, including different columns //onload (function($) $.fn.myGridFn = function(options){ $(this).jqGrid('GridUnload'); $(this).jqGrid(options.gridoptions); //.... $('#select').change(function(){ switch($(this).val()) { case 'grid1': $('#grid').myGridFn({gridoptions:{/*grid1 options*/}}); break; case 'grid2': $('#grid').myGridFn({gridoptions:{/*grid2 options*/}}); break; } }); })(jQuery); //... <table id="grid"></table> What I get is the grid unloading, then I have to change the selection in the select element and back again to load the new grid. Updated: If I replace the $(this) in the plugin with the actual element selector $('#grid') - it works just fine, I cant do this in my real app because the plugin is used by several other table elements and grids

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• HQL make query searching by date (Java+NetBeans)

  - by Zloy Smiertniy

  Hi all I have the following issue. I have a table of reserves in my MySQL DB, the date columns is defined DATETIME. I need to make a query using hibernate to find all reserves in one day no matter the hour, just that its the same year month and date, and I'm doing this public List<Reserve> bringAllResByDate(Date date){ em = emf.createEntityManager(); Query q = em.createQuery("SELECT r FROM Reserve r WHERE r.date=:date "); q.setParameter("date", date); ... I really dont know how to make it compare, and bring me just those from the specified date, any help??

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• What to do with a big image that's slowing website loading down significantly

  - by Dave

  Hi I'm working on a website that's already been designed by someone else. The designer has used a big image (900x700 100KB) which contains a big logo right across the top, then the background for two columns. This image loads every time a page is loaded as it forms the basis for the website. What should I do with it to improve loading time? I'm considering splitting it up into two or more images, especially the logo on the top. Does splitting up images like that decrease loading time in any significant way? Thanks -edit: Also, all the images are .jpg, would changing this to .gif or .png help anything?

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• Avoiding seasonality assumption for stl() or decompose() in R

  - by user303922

  Hello everybody, I have high frequency commodity price data that I need to analyze. My objective is to not assume any seasonal component and just identify a trend. Here is where I run into problems with R. There are two main functions that I know of to analyze this time series: decompose() and stl(). The problem is that they both take a ts object type with a frequency parameter greater than or equal to 2. Is there some way I can assume a frequency of 1 per unit time and still analyze this time series using R? I'm afraid that if I assume frequency greater than 1 per unit time, and seasonality is calculated using the frequency parameter, then my forecasts are going to depend on that assumption. names(crude.data)=c('Date','Time','Price') names(crude.data) freq = 2 win.graph() plot(crude.data$Time,crude.data$Price, type="l") crude.data$Price = ts(crude.data$Price,frequency=freq) I want frequency to be 1 per unit time but then decompose() and stl() don't work! dim(crude.data$Price) decom = decompose(crude.data$Price) win.graph() plot(decom$random[2:200],type="line") acf(decom$random[freq:length(decom$random-freq)]) Thank you.

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• Database design: Calculating the Account Balance

  - by 001

  How do I design the database to calculate the account balance? 1) Currently I calculate the account balance from the transaction table In my transaction table I have "description" and "amount" etc.. I would then add up all "amount" values and that would work out the user's account balance. I showed this to my friend and he said that is not a good solution, when my database grows its going to slow down???? He said I should create separate table to store the calculated account balance. If did this, I will have to maintain two tables, and its risky, the account balance table could go out of sync. Any suggestion? EDIT: OPTION 2: should I add an extra column to my transaction tables "Balance". now I do not need to go through many rows of data to perform my calculation. Example John buys $100 credit, he debt $60, he then adds $200 credit. Amount $100, Balance $100. Amount -$60, Balance $40. Amount $200, Balance $240.

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