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• redirect gridview selected row data to two different pages on clicking on two different select button asp.net?

  - by user559800

  Ihave a gridview item template field namely Status as mentioned above ... i want when user click on hold button of particular row then the record from the particular row is transfered to another page. ... means.... if i click on the hold button of 1st row of gridview then seats=35 and booking closed =08:00:00 PM willbe trasferred to Me.Response.Redirect("Select_seats.aspx?s_no=" & label22.Text.ToString & "&" & "journey=" & label6.Text & "&" & "seater=" & label4.Text & "&" & "sleeper=" & label2.Text & "&" & "service=" & lab5.Text.ToString) .. and if i click on the manage button of same row then the record of that row will be transferred to Me.Response.Redirect("Select_nfo.aspx?s_no=" & label22.Text.ToString & "&" & "journey=" & label6.Text & "&" & "seater=" & label4.Text & "&" & "sleeper=" & label2.Text & "&" & "service=" & lab5.Text.ToString)

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• Most watched videos this week

  - by Jan Hancic

  I have a youtube like web-page where users upload&watch videos. I would like to add a "most watched videos this week" list of videos to my page. But this list should not contain just the videos that ware uploaded in the previous week, but all videos. I'm currently recording views in a column, so I have no information on when a video was watched. So now I'm searching for a solution to how to record this data. The first is the most obvious (and the correct one, as far as I know): have a separate table in which you insert a new line every time you want to record a new view (storing the ID of the video and the timestamp). I'm worried that I would quickly get huge amounts of data in this table, and queries using this table would be extremely slow (we get about 3 million views a month). The second solution isn't as flexible but is more easy on the database. I would add 7 columns to the "videos" table (one for each day of the week): views_monday, views_tuesday , views_wednesday, ... And increment the value in the correct column based on the day it is. And I would reset the current day's column to 0 at midnight. I could then easily get the most watched videos of the week by summing this 7 columns. What do you think, should I bother with the first solution or will the second one suffice for my case? If you have a better solution please share! Oh, I'm using MySQL.

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• Use MySQL trigger to update another table when duplicate key found

  - by Jason

  Been scratching my head on this one, hoping one of you kind people and direct me towards solving this problem. I have a mysql table of customers, it contains a lot of data, but for the purpose of this question, we only need to worry about 4 columns 'ID', 'Firstname', 'Lastname', 'Postcode' Problem is, the table contains a lot of duplicated customers. A new table is being created where each customer is unique and for us, we decide a unique customer is based on 'Firstname', 'Lastname' and 'Postcode' However, (this is the important bit) we need to ensure each new "unique" customer record also can be matched to the original multiple entries of that customer in the original table. I believe the best way to do this is to have a third table, that has 'NewUniqueID', 'OldCustomerID'. So we can search this table for 'NewUniqueID' = '123' and it would return multiple 'OldCustomerID' values where appropriate. I am hoping to make this work using a trigger and the on duplicate key syntax. So what would happen is as follows: An query is run taking the old customer table and inserting it in to the new unique table. (A standard Insert Select query) On duplicate key continue adding records, but add one entry in to the third table noting the 'NewUniqueID' that duped along with the 'OldCustomerID' of the record we were trying to insert. Hope this makes sense, my apologies if it isn't clear. I welcome and appreciate any thoughts on this one! Many thanks Jason

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• Join unrelated tables through a second level connected table

  - by Andy M

  Hello! I have two tables of activities on a page: Views & Comments. Views id timestamp project_id user_id page_id Comments id timestamp project_id user_id page_id comment Pages id project_id title Now pages are related to projects: Projects id account_id title I am trying to create a summary page that combines views and comments ordered by time (so that the most recent views/comments are at the beginning, grouped by projects. Also, only projects for a specific account. So the result could potentially be: Project 1 View 5 (June 20th) View 4 (June 18th) Comment 5 (June 15th) Comment 4 (June 14th) Comment 3 (June 12th) Project 3 View 3 (June 10th) View 2 (June 8th) Comment 2 (June 7th) Project 2 View 1 (June 5th) Comment 1 (June 4th) If you could help with how to do this using SQL (or even doctrine) that would be awesome. Thank you.

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• How do I set the LRECL in C#.NET?

  - by donde

  I have been trying to ftp a dtl file from .net to, what I beleive, is an AS400. The error being reported back to me is: "One or more lines have been truncated" and the admin is saying the file is coming over with 256 lines that have variable length columns. I found this explanation online: we have to establish defaults because no specifics about the file exist. The default RECFM is V and LRECL is 256. This means that SAS will scan the input record looking for the CR & LF to tell us that we are at the EOR. If the marker isn't found within the limit of the LRECL, SAS discards the data from the LRECL value to the end of the record and adds a message to the Log that "One or more lines have been truncated". So I need to set the LRECL. How do I do this in C# .NET? FtpWebRequest ftp = (FtpWebRequest)FtpWebRequest.Create(ftpfullpath); ftp.Credentials = new NetworkCredential(user, pwd); ftp.KeepAlive = false; ftp.UseBinary = false; ftp.Method = WebRequestMethods.Ftp.UploadFile; FileStream fs = File.OpenRead(inputfilepath + ftpfileName); byte[] buffer = new byte[fs.Length]; fs.Read(buffer, 0, buffer.Length); fs.Close(); Stream ftpstream = ftp.GetRequestStream(); int i = 0; int intBlock = 1786; int intBuffLeft = buffer.Length; while (i < buffer.Length) { if (intBuffLeft >= 1786) { ftpstream.Write(buffer, i, intBlock); } else { ftpstream.Write(buffer, i, intBuffLeft); } i += intBlock; intBuffLeft -= 1786; } ftpstream.Close();

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• [Symfony] Admin generator and i18n

  - by David

  I have read lots of questions about i18n, but I haven't found any about performance. I have a simple backend app listing the contents of an ads table. These ads have a category, that is translated in some languages (it's defined as i18n in the Doctrine schema). So, when I add a "table_method" in my generator.yml to include de Category table, it reduces the number of queries, but there are yet some of them referencing i18n translation tables. So, if I add the category Translation table to the query, it reduces even more the queries BUT it increases the processing time considerably. Why this time penalty? Just because of the translation table? And why isn't the filter using this method to avoid so many translation queries as well? I mean, if I want to filter by category, it is making one query per category to include the translation table. Why??

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• SQL Server race condition issue with range lock

  - by Freek

  I'm implementing a queue in SQL Server (please no discussions about this) and am running into a race condition issue. The T-SQL of interest is the following: set transaction isolation level serializable begin tran declare @RecordId int declare @CurrentTS datetime2 set @CurrentTS=CURRENT_TIMESTAMP select top 1 @RecordId=Id from QueuedImportJobs with (updlock) where Status=@Status and (LeaseTimeout is null or @CurrentTS>LeaseTimeout) order by Id asc if @@ROWCOUNT> 0 begin update QueuedImportJobs set LeaseTimeout = DATEADD(mi,5,@CurrentTS), LeaseTicket=newid() where Id=@RecordId select * from QueuedImportJobs where Id = @RecordId end commit tran RecordId is the PK and there is also an index on Status,LeaseTimeout. What I'm basically doing is select a record of which the lease happens to be expired, while simultaneously updating the lease time with 5 minutes and setting a new lease ticket. So the problem is that I'm getting deadlocks when I run this code in parallel using a couple of threads. I've debugged it up to the point where I found out that the update statement sometimes gets executing twice for the same record. Now, I was under the impression that the with (updlock) should prevent this (it also happens with xlock btw, not with tablockx). So it actually look like there is a RangeS-U and a RangeX-X lock on the same range of records, which ought to be impossible. So what am I missing? I'm thinking it might have something to do with the top 1 clause or that SQL Server does not know that where Id=@RecordId is actually in the locked range? Deadlock graph: Table schema (simplified):

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• Why is $file empty in custom symfony file validator?

  - by codecowboy

  I am setting a custom file validator for a file input field in Symfony 1.4 (Doctrine) $this-setValidator('filename', new sfValidatorFile(array( 'mime_types' = 'web_images', 'path' = sfConfig::get('sf_upload_dir').'/animals', 'validated_file_class' = 'CustomValidatedFile', 'required' =false ))); I then want to override the save method to generate some thumbnails: class CustomValidatedFile extends sfValidatedFile { private $savedFilename; // Override sfValidatedFile's save method public function save($file = null, $fileMode = 0666, $create = true, $dirMode = 0777) { $this-savedFilename = $this-generateFilename(); // This makes sure we use only one savedFilename (it will be the first) if ($this-savedFilename === null ) { $this-savedFilename = $file; } $thumbnail = new sfThumbnail(150,150); $thumbnail-loadFile($this-getTempName()); $thumbnail-save(sfConfig::get('sf_upload_dir').'/thumbnails/thumb_'.$this-savedFilename); // Let the original save method do its magic :) return parent::save($this->savedFilename, $fileMode, $create, $dirMode); } } This fails with the error "The file "" is not readable." This is coming from sfThumbnailPlugin because the value of $file is null. My question is why is $file null?

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• how to add an ajax jQuery code, that return a row from php file [DB] and then change the value of input text?

  - by Nisreen KH

  //this is a code in php which is fetch a record from database <?php include("dbconn.inc"); $data=mysql_query("SELECT `subtitle`, `mian-title`, `page_num`, `note_path`, `flash_path` FROM `main-page` WHERE `page_num` =".$r." LIMIT 1"); echo $data; if (mysql_num_rows($data) == 0) { echo "No rows found, nothing to print so am exiting"; exit; } while ($row = mysql_fetch_assoc($data)) { echo $row['page_num']; } include("close.php"); ?> //and this is a code in html <form method="post" action="data.php"> <input name="Button1" type="submit" value="&lt;&lt;" /> <input name="test" style="width: 31px; height: 23px" type="text" /> // this is a value of page_num in DB. <input name="Button2" type="submit" value="&gt;&gt;" > </form> //i want to add an ajax code to retrieve the record from php code, and then change the input values depends on returned data ,and also to prevent refreshing the page always!!

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• How to effectively execute this cron job?

  - by Lost_in_code

  I have a table with 200 rows. I'm running a cron job every 10 minutes to perform some kind of insert/update operation on the table. The operation needs to be performed only on 5 rows at a time every time the cron job runs. So in first 10 mins records 1-5 are updated, records 5-10 in the 20th minute and so on. When the cron job runs for the 20th time, all the records in the table would have been updated exactly once. This is what is to be achieved at least. And the next cron job should repeat the process again. The problem: is that, every time a cron job runs, the insert/update operation should be performed on N rows (not just 5 rows). So, if N is 100, all records would've been updated by just 2 cron jobs. And the next cron job would repeat the process again. Here's an example: This is the table I currently have (200 records). Every time a cron job executes, it needs to pick N records (which I set as a variable in PHP) and update the time_md5 field with the current time's MD5 value. +---------+-------------------------------------+ | id | time_md5 | +---------+-------------------------------------+ | 10 | 971324428e62dd6832a2778582559977 | | 72 | 1bd58291594543a8cc239d99843a846c | | 3 | 9300278bc5f114a290f6ed917ee93736 | | 40 | 915bf1c5a1f13404add6612ec452e644 | | 599 | 799671e31d5350ff405c8016a38c74eb | | 56 | 56302bb119f1d03db3c9093caf98c735 | | 798 | 47889aa559636b5512436776afd6ba56 | | 8 | 85fdc72d3b51f0b8b356eceac710df14 | | .. | ....... | | .. | ....... | | .. | ....... | | .. | ....... | | 340 | 9217eab5adcc47b365b2e00bbdcc011a | <-- 200th record +---------+-------------------------------------+ So, the first record(id 10) should not be updated more than once, till all 200 records are updated once - the process should start over once all the records are updated once. I have some idea on how this could be achieved, but I'm sure there are more efficient ways of doing it. Any suggestions?

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• How do you bind SQL Data to a .NET DataGridView?

  - by Jordan S

  I am trying to bind a table in an SQL database to a DataGridView Control. I would like to make it so that when the user enters a new line of data in the DataGridView that a record is automatically added to the database. Is there a way to do this using LINQ to SQL? I have tried using the code below but after I add a new entry I dont think the data gets added to the DB. Please Help! BOMClassesDataContext DB = new BOMClassesDataContext(); var mfrs = from m in DB.Manufacturers select m; BindingSource bs = new BindingSource(); bs.DataSource = mfrs; dataGridView1.DataSource = bs; I tried adding DB.SubmitChanges() to the CellValueChanged eventhandler and that partially works. If I click the bottom empty row it automatically fills in the ID (identity) column of the table with a "0" instead of the next unused value. If I change that value manually to the next available then it adds the new record fine but if I leave it at 0 it does nothing. How can i fix this?

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• frameworks for coding a php library?

  - by ajsie

  there are plenty of frameworks for coding MVC web applications. this time im going to code a library (think of Doctrine or Solr) with a bunch of class files. u just include a bootstrap or a class file and you are ready to use my classes. i have never tried to code a library before and intend to code one for learning purpose so that i can use various design patterns i have learned. are there any great frameworks for this, how i should organize the different class files, where i can put configuration files and so on? tutorials or other information would be great too. thanks

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• Entity Framework one-to-one relationship mapping flattened in code

  - by Josh Close

  I have a table structure like so. Address: AddressId int not null primary key identity ...more columns AddressContinental: AddressId int not null primary key identity foreign key to pk of Address County State AddressInternational: AddressId int not null primary key identity foreign key to pk of Address ProvinceRegion I don't have control over schema, this is just the way it is. Now, what I want to do is have a single Address object. public class Address { public int AddressId { get; set; } public County County { get; set; } public State State { get; set } public ProvinceRegion { get; set; } } I want to have EF pull it out of the database as a single entity. When saving, I want to save the single entity and have EF know to split it into the three tables. How would I map this in EF 4.1 Code First? I've been searching around and haven't found anything that meets my case yet. UPDATE An address record will have a record in Address and one in either AddressContinental or AddressInternational, but not both.

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• How to allow certain HTML tags in a form field in Symfony 1.2

  - by camomileCase

  I'm playing around with Symfony and have encountered a road block. I created a model "CmsPage" which has a field called "content" which is stored as a clob (this is specific to doctrine I believe). When I created the app I set "--escaping-strategy=on" so if I enter any html when editing a CmsPage that gets encoded with html entities or something along those lines. I would like to allow html in this field and a quick googling hasn't helped much. Maybe I'm searching for the wrong terms. Anywho I would like to disable character escaping for this field and possibly only allow a small selection of html tags. What is the correct way to do this in Symfony?

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• Do I lose the benefits of macro recording if I develop Excel apps in Visual Studio?

  - by DanM

  I've written lots of Excel macros in the past using the following development process: Record a macro. Open the VBA editor. Edit the macro. I'm now experimenting with a Visual Studio 2008 "Excel 2007 Add-In" project (C#), and I'm wondering if I will have to give up this development process. Questions: I know I can still record macros using Excel, but is there any way to access the resulting code in Visual Studio? Or do I just have to copy and paste then C#-ize it? What happens with my "Personal Macro Workbook"? Can I use the macros I have stored in there within C#? Or is there some way to convert them to C#? If there is some support for opening and editing VBA macros in Visual Studio, can you provide a very brief summary of how it works or point me to a good reference? Do you have any other tips for transitioning from writing macros in VBA using Excel's built-in editor to writing them in C# with Visual Studio?

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• how to prevent database to add slash to quotes

  - by black sensei

  i know this sounds really common and so trivial but , am having a challenge here. I have a web site with Zend/Doctrine and i use ckeditor for the backend management. after uploading the site i've realized that during edit testing the look and feel of the site is messed up. with the help of firebug, i've seen that there are slashes all over the html. after inline edition, the look and feel came back to normal. There are so many files , i can't think of doing other decoding before outputting data from mysql. What options do i have to solve this problem. the site is up already and i feel a bit unconfortable about this. Can anyone give a hint? thanks

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• Do you catch expected exceptions in the controller or business service of your asp.net mvc application

  - by Pascal

  I am developing an asp.net mvc application where user1 could delete data records which were just loaded before by user2. User2 either changes this non-existent data record (Update) or is doing an insert with this data in another table that a foreign-key constraint is violated. Where do you catch such expected exceptions? In the Controller of your asp.net mvc application or in the business service? Just a sidenote: I only catch the SqlException here if its a ForeignKey constraint exception to tell the user that another user has deleted a certain parent record and therefore he can not create the testplan. But this code is not fully implemented yet! Controller:   public JsonResult CreateTestplan(Testplan testplan)   {    bool success = false;    string error = string.Empty;    try   {    success = testplanService.CreateTestplan(testplan);    }   catch (SqlException ex)    {    error = ex.Message;    }    return Json(new { success = success, error = error }, JsonRequestBehavior.AllowGet);   } OR Business service: public Result CreateTestplan(Testplan testplan) { Result result = new Result(); try { using (var con = new SqlConnection(_connectionString)) using (var trans = new TransactionScope()) { con.Open(); _testplanDataProvider.AddTestplan(testplan); _testplanDataProvider.CreateTeststepsForTestplan(testplan.Id, testplan.TemplateId); trans.Complete(); result.Success = true; } } catch (SqlException e) { result.Error = e.Message; } return result; } then in the Controller: public JsonResult CreateTestplan(Testplan testplan)   {    Result result = testplanService.CreateTestplan(testplan);       return Json(new { success = result.success, error = result.error }, JsonRequestBehavior.AllowGet);   }

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• SQL Binary Microsoft Access - Combining two tables if specific field values are equal

  - by Jordan

  I am new to Microsoft Access and SQL but have a decent programming background and I believe this problem should be relatively simple. I have two tables that I have imported into Access. I will give you a little context. One table is huge and contains generic, global data. The other table is still big but contains specific, regional data. There is only one common field (or column) between the two tables. Let’s call this common field CF. The other fields in both tables are different. I’ll take you through one iteration of what I need to do. I need to take each CF value in the regional, smaller table and find the common CF value in the larger, global table. After finding the match, I need to take the whole “record” or “row” from the global data and copy it over to the corresponding record in the smaller regional table (This should involve creating the new fields). I need to do this for all CF values in the regional, smaller table. I was recommended to use SQL and a binary search, but I am unfamiliar. Let me know if you have any questions. I appreciate the help!

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• Unable to delete inherited entity class in EF4

  - by Coding Gorilla

  I have two entities in an EF4 model (using Model First), let's call them EntityA and EntityB. EntityA is marked as abstract, and EntityB inherits from EntityA. They are similar to the following: public class EntityA { public Guid Id; public string Name; public string Uri; } public class EntityB : EntityA { public string AnotherProperty; } The generated database tables look as I would expect them, with EntityA as on table, and then another table like: EntityA_EntityB Id (PK, FK, uniqueidentifier) AnotherProperty (varchar) There is a foreign key constraint on EntityA_EntityB that references EntityA's Id property, no cascades are configured (although I did try changing these myself). The problem is that when I attempt to do something like: Context.DeleteObject(EntityA_EntityB); EF attempts to delete the EntityA_EntityB table record before deleting the EntityA table record, which of course violates the foreign key constraint on EntityA_EntityB table. Using EFProfiler I see the following commands being sent to the database: delete [dbo].[EntityA_EntityB] where (([Id] = '5c02899f-09ea-2ed9-d44b-01aef80f6b64' /* @0 */) followed by delete [dbo].[EntityA] where ([Id] = '5c02899f-09ea-2ed9-d44b-01aef80f6b64' /* @0 */) I'm completely stumped as to how to get around this problem. I would think the EF should know that it needs to delete the base class first, before deleting the inherited class. I know I could do some triggers or other database type solutions, but I'd rather avoid doing that if I can. All my classes are POCO built using some customized T4 templates. I don't want to paste in a lot of extraneous code, but if you need more information I'll provide what I can.

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• Adding a column to a model at runtime (without additional tables) in rails

  - by Marek

  I'm trying to give admins of my web application the ability to add some new fields to a model. The model is called Artwork and i would like to add, for instante, a test_column column at runtime. I'm just teting, so i added a simple link to do it, it will be of course parametric. I managed to do it through migrations: def test_migration_create Artwork.add_column :test_column, :integer flash[:notice] = "Added Column test_column to artworks" redirect_to :action => 'index' end def test_migration_delete Artwork.remove_column :test_column flash[:notice] = "Removed column test_column from artworks" redirect_to :action => 'index' end It works, the column gets added/ removed to/from the databse without issues. I'm using active_scaffold at the moment, so i get the test_column field in the form without adding anything. When i submit a create or an update, however, the test_column does not get updated and stay empty. Inspecting the parameters, i can see: Parameters: {"commit"=>"Update", "authenticity_token"=>"37Bo5pT2jeoXtyY1HgkEdIhglhz8iQL0i3XAx7vu9H4=", "id"=>"62", "record"=>{"number"=>"test_artwork", "author"=>"", "title"=>"Opera di Test", "test_column"=>"TEEST", "year"=>"", "description"=>""}} the test_column parameter is passed correctly. So why active record keeps ignoring it? I tried to restart the server too without success. I'm using ruby 1.8.7, rails 2.3.5, and mongrel with an sqlite3 database. Thanks

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• Cached data accessed by reference?

  - by arthurdent510

  I am running into an odd problem, and this is the only thing I can think of. I'm storing a list in cache, and I am randomly losing items from my list as users use the site. I have a class that is called that either goes to cache and returns the list from there, or if the cache is over a certain time frame old, it goes to the database and refreshes the cache. So when I pull the data from cache, this is what it looks like.... results = (List<Software>)cache["software"]; And then I return results and do some processing, filter for security, and eventually it winds up on the screen. For each Software record, there can be multiple resources attached to it, and based on how the security goes they may see some, all, or none of the records. So in the security check it will remove some of those resources from the software record. So my question is.... when I return my results list, is it a reference directly to the cache object? So when I remove a resource from the software object, it is really removing from cache as well? If that is the case, is there any way to not return it as a reference? Thanks!

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• Why does this SELECT ... JOIN statement return no results?

  - by Stephen

  I have two tables: 1. tableA is a list of records with many columns. There is a timestamp column called "created" 2. tableB is used to track users in my application that have locked a record in tableA for review. It consists of four columns: id, user_id, record_id, and another timestamp collumn. I'm trying to select up to 10 records from tableA that have not been locked by for review by anyone in tableB (I'm also filtering in the WHERE clause by a few other columns from tableA like record status). Here's what I've come up with so far: SELECT tableA.* FROM tableA LEFT OUTER JOIN tableB ON tableA.id = tableB.record_id WHERE tableB.id = NULL AND tableA.status = 'new' AND tableA.project != 'someproject' AND tableA.created BETWEEN '1999-01-01 00:00:00' AND '2010-05-06 23:59:59' ORDER BY tableA.created ASC LIMIT 0, 10; There are currently a few thousand records in tableA and zero records in tableB. There are definitely records that fall between those timestamps, and I've verified this with a simple SELECT * FROM tableA WHERE created BETWEEN '1999-01-01 00:00:00' AND '2010-05-06 23:59:59' The first statement above returns zero rows, and the second one returns over 2,000 rows.

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• Improve SQL strategy - denormalize in object-children-images case

  - by fesja

  Hi, I have a Tour object which has many Place objects. For the list of tours, I want to show some info of the tour, the number of places of the tour, and three Place's images. Right one my SQL queries are (i'm using Doctrine with Symfony on MySQL) get Tour get Tour 1 places get Tour 2 places get Tour 3 places ... get Tour n places If I have a three Tour list, it's not so bad; but I'm sure it can get bad if I do a 10-20 tour-list. So, thinking on how to improve the queries I've thought of several measures: Having a place count cache Storing the urls of three images on a new tour field. The problem with 2. is that if I change the image, I have to check all the tours to update that image for another one. What solution do you think is best to scale the system in a near future? Any other suggestion. thanks!

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• Is this use of PreparedStatements in a Thread in JAVA correct?

  - by Gormcito

  I'm still an undergrad just working part time and so I'm always trying to be aware of better ways to do things. Recently I had to write a program for work where the main thread of the program would spawn "task" threads (for each db "task" record) which would perform some operations and then update the record to say that it has finished. Therefore I needed a database connection object and PreparedStatement objects in or available to the ThreadedTask objects. This is roughly what I ended up writing, is creating a PreparedStatement object per thread a waste? I thought static PreparedStatments could create race conditions... Thread A stmt.setInt(); Thread B stmt.setInt(); Thread A stmt.execute(); Thread B stmt.execute(); A´s version never gets execed.. Is this thread safe? Is creating and destroying PreparedStatement objects that are always the same not a huge waste? public class ThreadedTask implements runnable { private final PreparedStatement taskCompleteStmt; public ThreadedTask() { //... taskCompleteStmt = Main.db.prepareStatement(...); } public run() { //... taskCompleteStmt.executeUpdate(); } } public class Main { public static final db = DriverManager.getConnection(...); }

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• merging two tables, while applying aggregates on the duplicates (max,min and sum)

  - by cloudraven

  I have a table (let's call it log) with a few millions of records. Among the fields I have Id, Count, FirstHit, LastHit. Id - The record id Count - number of times this Id has been reported FirstHit - earliest timestamp with which this Id was reported LastHit - latest timestamp with which this Id was reported This table only has one record for any given Id Everyday I get into another table (let's call it feed) with around half a million records with these fields among many others: Id Timestamp - Entry date and time. This table can have many records for the same id What I want to do is to update log in the following way. Count - log count value, plus the count() of records for that id found in feed FirstHit - the earliest of the current value in log or the minimum value in feed for that id LastHit - the latest of the current value in log or the maximum value in feed for that id. It should be noticed that many of the ids in feed are already in log. The simple thing that worked is to create a temporary table and insert into it the union of both as in Select Id, Min(Timestamp) As FirstHit, MAX(Timestamp) as LastHit, Count(*) as Count FROM feed GROUP BY Id UNION ALL Select Id, FirstHit,LastHit,Count FROM log; From that temporary table I do a select that aggregates Min(firsthit), max(lasthit) and sum(Count) Select Id, Min(FirstHit),Max(LastHit),Sum(Count) FROM @temp GROUP BY Id; and that gives me the end result. I could then delete everything from log and replace it with everything with temp, or craft an update for the common records and insert the new ones. However, I think both are highly inefficient. Is there a more efficient way of doing this. Perhaps doing the update in place in the log table?

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