Search Results

Search found 18695 results on 748 pages for 'query manipulation'.

Page 489/748 | < Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >

  • What's the different between these 2 mysql queries? one using left join

    - by Lyon
    Hi, I see people using LEFT JOIN in their mysql queries to fetch data from two tables. But I normally do it without left join. Is there any differences besides the syntax, e.g. performance? Here's my normal query style: SELECT * FROM table1 as tbl1, table2 as tbl2 WHERE tbl1.id=tbl2.table_id as compared to SELECT * FROM table1 as tbl1 LEFT JOIN table2 as tbl2 on tbl1.id=tbl2.id Personally I prefer the first style...hmm..

    Read the article

  • .NET - Very strange NullReferenceException?

    - by ropstah
    How can I get a NullReferenceException in the following scenario? Dim langs As IEnumerable(Of SomeCustomObject) = //some LINQ query If langs Is Nothing Then Return Nothing If langs.Count = 1 Then //NullReferenceException here What am I missing here? Debug shows that langs is really just a LINQ queryresult without any results...

    Read the article

  • Best Practice : Import CSV to MYSQL Database using PHP 5.x

    - by ArneRie
    Howdy Folks, what is the best solution to import large amounts of records into an MySQL or Oracle Database. I Think there are two ways : Insert every record with an persistent connection Create on BIG SQL-Statement and query the Database Iam not sure wich is performing better ? Is there any Best Practice Solutions for this kind of operation ??

    Read the article

  • Programicaly measure size and way-order of L1 and L2 caches

    - by osgx
    Hello How can I measure programicaly (not query the OS, but measure) the size and order of associativity of L1 and L2 caches (data caches)? Assumtions about system: It has L1 and L2 cache (may be L3 too, may be cache sharing), It may have a hardware prefetch unit (just like P4+), it has a stable clocksource (tickcounter or good HPET for gettimeofday). There are no assumtions about OS (it can be Linux, Windows, smth non-standart), and we can't use posix queries. Language is C. And Compiler optimizations may be disabled.

    Read the article

  • How effective are technical test(s) and is it necessary?

    - by The Elite Gentleman
    Hi everyone, I recently took a Java technical test (for a company who wanted are looking for senior java developers) and, funny enough, I only realised the technical terms of what I've been doing all along after I've written the test. I'm not too IT jargon when it comes to development but I can pretty much code and create solutions unaware that I'm using design pattern (or the specifics of that design pattern) or technology. I learned things such as JMS, Frameworks, etc. while programming at home and having to google stuff online to problems I have. Others e.g. IoC, Surrogates in Databases, etc., I have used extensively without knowing that it had a name for it. Do you think that these technical test are effective and why? What interesting questions did you find that boggled your brains out while the clock kept ticking? Seeing that IT is vastly evolving at a rapid rate, do we have to constantly be updated with new terms that comes out? Some questions I was asked : What object oriented principle is violated by this architectural mechanism for dot notation? Is indexing tables effective for range query or point query search? What is ThreadLocal and what is it used for? Method overloading vs Method overriding. What is the difference between the 2? What is dynamic binding? Now, imagine my poor head trying to understand these jargons (considering I use it almost everyday) PS The question was not a programming question, where you have a problem and write code to solve it. Rather, a thinking type question and you write answers (against the clock). Update I clearly didn't come out clearly as I should have. There are those that are technically "book smart" but with very little hands-on experience and vice versa. So, the question (in connection to what I've asked) is that are these technical test seeking "book smart" people or people with lots of hands-on experience (some who are not that well clued up with too much book-smart jargons). How effective is it then, for companies to look for developers if most of the questions are too terminology-centric? (if that's the correct term, :))

    Read the article

  • MVC model flow?

    - by fuzzygoat
    I am setting up an application using the MVC model and I have a query regrading the flow of information from the UI to the data model. What I need to do is place data from the UI in the model, what I have done is write a method in the view which collects the required data in an object and then passes it to the model. The model then takes ownership of the data so that the view can release its ownership. Does this sound sensible?

    Read the article

  • PHP & MySQL Pagination

    - by Francesc
    Hi. I have a MySQL query SELECT * FROM 'redirect' WHERE 'user_id'= \''.$_SESSION['user_id'].' \' ORDER BY 'timestamp'` I want to paginate 10 results per page. How Can I do it?

    Read the article

  • Set HTML dropdown selected option using JSTL

    - by sarah
    In the same context i have another query ${productSubCategoryList} and the corresponding setting in request is like for(int i=0;i } here i have multiple select drop down ,even though i get the return value from for as two ,in the UI only one data is getting higlighted not the second one,What is wrong in the code ?

    Read the article

  • Hard link and Symbolic links in Unix

    - by darkie15
    Hi All, I just wanted to clarify if a hard/symbolic link is actually a file that is created ?? I ran the command: ln source hardlink ln -s source softlink -- The ls command shows this 2 links as a file. So my query is, does ln / ln -s actually create a file? Regards, Shyam

    Read the article

  • Create a user-defined aggregate without SQL CLR

    - by David Pfeffer
    I am planning on deploying a database to SQL Azure, so I cannot use the SQL CLR. However, I have a need to create an aggregate function -- in my case, I need to STUnion a bunch of Geography objects together. (Azure is expected to support Spatial by June.) Is there another way to accomplish this, without making use of the CLR, in a query? Or do I have to create a UDF that will take a table as a parameter and return the aggregate?

    Read the article

  • PHP and MySql trouble

    - by Espen Arnoy
    I am having trouble making this seemingly simple MySql query work. Can anyone spot the problem? <?php include "config.php"; $offerid = $_POST["offerid"]; $ip = $_SERVER["REMOTE_ADDR"]; mysql_query("INSERT INTO voted (offerid,ip) VALUES (".$offerid.",".$ip.")"); ?>

    Read the article

  • Cakephp Insert Ignore Feature?

    - by SeanDowney
    Is there a way to do an "insert ignore" in cake without using a model-query function? $this->Model->save(array( 'id' => NULL, 'guid' => $guid, 'name' => $name, )); Generates error: Warning (512): SQL Error: 1062: Duplicate entry 'GUID.....' for key 'unique_guid' [CORE/cake/libs/model/datasources/dbo_source.php, line 524] It would be great to be able to set some flag or option that says "don't care"

    Read the article

  • Rails Joins and include columns from joins table

    - by seth.vargo
    I don't understand how to get the columns I want from rails. I have two models - A User and a Profile. A User :has_many Profile (because users can revert back to an earlier version of their profile): > DESCRIBE users; +----------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | username | varchar(255) | NO | UNI | NULL | | | password | varchar(255) | NO | | NULL | | | last_login | datetime | YES | | NULL | | +----------------+--------------+------+-----+---------+----------------+   > DESCRIBE profiles; +----------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | user_id | int(11) | NO | MUL | NULL | | | first_name | varchar(255) | NO | | NULL | | | last_name | varchar(255) | NO | | NULL | | | . . . . . . | | . . . . . . | | . . . . . . | +----------------+--------------+------+-----+---------+----------------+ In SQL, I can run the query: > SELECT * FROM profiles JOIN users ON profiles.user_id = users.id LIMIT 1; +----+-----------+----------+---------------------+---------+---------------+-----+ | id | username | password | last_login | user_id | first_name | ... | +----+-----------+----------+---------------------+---------+---------------+-----+ | 1 | john | ****** | 2010-12-30 18:04:28 | 1 | John | ... | +----+-----------+----------+---------------------+---------+---------------+-----+ See how I get all the columns for BOTH tables JOINED together? However, when I run this same query in Rails, I don't get all the columns I want - I only get those from Profile: # in rails console >> p = Profile.joins(:user).limit(1) >> [#<Profile ...>] >> p.first_name >> NoMethodError: undefined method `first_name' for #<ActiveRecord::Relation:0x102b521d0> from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.1/lib/active_record/relation.rb:373:in `method_missing' from (irb):8 # I do NOT want to do this (AKA I do NOT want to use "includes") >> p.user >> NoMethodError: undefined method `user' for #<ActiveRecord::Relation:0x102b521d0> from /Library/Ruby/Gems/1.8/gems/activerecord-3.0.1/lib/active_record/relation.rb:373:in method_missing' from (irb):9 I want to (efficiently) return an object that has all the properties of Profile and User together. I don't want to :include the user because it doesn't make sense. The user should always be part of the most recent profile as if they were fields within the Profile model. How do I accomplish this?

    Read the article

  • Invoke Python modules from Java

    - by user36813
    I have a Python interface of a graph library written in C - igraph (the name of library). My need is to invoke the python modules pertaining to this graph library from Java code. It goes like this, the core of library is in c. This core has been imported into Python and interfaces to the functions embedded in core are available in Python. My project's rest of the code is in Java and hence I would like to call the graph functions by Java as well. Jython - which lets you invoke python modules with in Java was an option.I went on trying Jython to discover that it will not work in my case as the core code is in C and Jython wont support anything that is imported as a c dll in python code.I also thought of opting for the approach of calling graph routines directly in c. That is without passing through Python code. I am assuming there must be something which lets you call c code from Java, how ever I am not good in C hence I did not go for it. My last resort seems to execute Python interpreter from command line using Java. But that is a dirty and shameless. Also to deal with the results produced by Python code I will have to write the results in a file and read it back in java. Again dirty way. Is there something that any one can suggest me? Thanks to every one giving time. Thanks Igal for answering. I had a look at it. At first glance it appears as if it is simply calling the python script. Jep jep = new Jep(false, SCRIPT_PATH, cl); jep.set("query", query); jep.runScript(SCRIPT_PATH + file); jep.close(); Isnt it very similar to what we would do if called the python interpreter from command line through a Java code. Runtime runtime = Runtime.getRuntime(); Process proc = runtime.exec("python test.py"); Concern is how do I use the results generated by Python script. The naive way is to write them to file and read it back in Java. I am searching for a smarter approach.Thanks for suggestion anyway.

    Read the article

  • full text search on multiple fields in diferrent tables

    - by crisgomez
    Hi, I want to create a a full text search usng ms sql 2005. here is the structure of my table User-contains fields of Id, fname,lname,email,alternativeemail Attachment-contains fields of id, name,category,filenameorurl Certification-contains of fileds of id, title,school,sdate,edate EducationalBackground-contain of fields of, id,qualification,sdate,edate,school,fieldofstudy EmploymentDetails-contain of fields position, positionlevelid,specializationid,description now the relationship of user to the other table is one to many relationship. now how can I create an effective query to have quick full text search and return the values of the different tables?any help please

    Read the article

  • MSSQL 2008 FTS CONTAINSTABLE Not Returning More Than Five Rows

    - by Elijah Glover
    I have a single table called "Indexes", it contains one nvarchar and three ntext columns (all Full Text Indexes). Index is up to date. CONTAINSTABLE(Indexes, *), 'test', 5) //5 results No matter what I change the above keyword too, it only returns the first 3-5 results. It should roughly return 90-120 results, for the above query. SELECT count(*) FROM Indexes WHERE [Description] like '%test%' //122 results How would I start to troubleshoot this problem?

    Read the article

  • Oracle "Partition By" Keyword

    - by Nalandial
    Can someone please explain what the "partition by" keyword does and give a simple example of it in action, as well as why one would want to use it? I have a SQL query written by someone else and I'm trying to figure out what it does. An example of partition by: SELECT empno, deptno, COUNT(*) OVER (PARTITION BY deptno) DEPT_COUNT FROM emp The examples I've seen online seem a bit too in-depth. Thanks in advance!

    Read the article

< Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >