Search Results

Search found 19425 results on 777 pages for 'output clause'.

Page 330/777 | < Previous Page | 326 327 328 329 330 331 332 333 334 335 336 337  | Next Page >

  • Is there a definitive reference document for Ruby syntax?

    - by JSW
    I'm searching for a definitive document on Ruby syntax. I know about the definitive documents for the core API and standard library, but what about the syntax itself? For instance, such a document should cover: reserved words, string literals syntax, naming rules for variables/classes/modules, all the conditional statements and their permutations, and so forth. I know there are many books and tutorials, yes, but every one of them is essentially a tutorial, each one having a range of different depth and focus. They will all, by necessity of brevity and narrative flow, omit certain details of the language that the author deems insignificant. For instance, did you know that you can use a case statement without an initial case value, and it will then execute the first true when clause? Any given Ruby book or tutorial may or may not cover that particular lesser-known functionality of the case syntax. It's not discussed in the section in "Programming Ruby" about case statements. But that is just one small example. So far the best documentation I've found is the rubyspec project, which appears to be an attempt to write a complete test suite for the language. That's not bad, but it's a bit hard to use from a practical standpoint as a developer working on my own projects. Am I just missing something or is there really no definitive readable document defining the whole of Ruby syntax?

    Read the article

  • MFC/CCriticalSection: Simple lock situation hangs

    - by raph.amiard
    I have to program a simple threaded program with MFC/C++ for a uni assignment. I have a simple scenario in wich i have a worked thread which executes a function along the lines of : UINT createSchedules(LPVOID param) { genProgThreadVal* v = (genProgThreadVal*) param; // v->searcherLock is of type CcriticalSection* while(1) { if(v->searcherLock->Lock()) { //do the stuff, access shared object , exit clause etc.. v->searcherLock->Unlock(); } } PostMessage(v->hwnd, WM_USER_THREAD_FINISHED , 0,0); delete v; return 0; } In my main UI class, i have a CListControl that i want to be able to access the shared object (of type std::List). Hence the locking stuff. So this CList has an handler function looking like this : void Ccreationprogramme::OnLvnItemchangedList5(NMHDR *pNMHDR, LRESULT *pResult) { LPNMLISTVIEW pNMLV = reinterpret_cast<LPNMLISTVIEW>(pNMHDR); if((pNMLV->uChanged & LVIF_STATE) && (pNMLV->uNewState & LVNI_SELECTED)) { searcherLock.Lock(); // do the stuff on shared object searcherLock.Unlock(); // do some more stuff } *pResult = 0; } The searcherLock in both function is the same object. The worker thread function is passed a pointer to the CCriticalSection object, which is a member of my dialog class. Everything works but, as soon as i do click on my list, and so triggers the handler function, the whole program hangs indefinitely.I tried using a Cmutex. I tried using a CSingleLock wrapping over the critical section object, and none of this has worked. What am i missing ?

    Read the article

  • MySQL: SELECT highest column value when WHERE finds similar entries

    - by Ike
    My question is comparable to this one, but not quite the same. I have a database with a huge amount of books, with different editions of some of the same book titles. I'm looking for an SQL statement giving me the highest edition number of each of the titles I'm selecting with a WHERE clause (to find specific book series). Here's what the table looks like: |id|title |edition|year| |--|-------------------------|-------|----| |01|Serie One Title One |1 |2007| |02|Serie One Title One |2 |2008| |03|Serie One Title One |3 |2009| |04|Serie One Title Two |1 |2001| |05|Serie One Title Three |1 |2008| |06|Serie One Title Three |2 |2009| |07|Serie One Title Three |3 |2010| |08|Serie One Title Three |4 |2011| |--|-------------------------|-------|----| The result I'm looking for is this: |id|title |edition|year| |--|-------------------------|-------|----| |03|Serie One Title One |3 |2009| |04|Serie One Title Two |1 |2001| |08|Serie One Title Three |4 |2011| |--|-------------------------|-------|----| The closest I got was using this statement: select id, title, max(edition), max(year) from books where title like "serie one%" group by name; but it returns the highest edition and year and includes the first id it finds: |--|-----------------------|-------|----| |01|Serie One Title One |3 |2009| |04|Serie One Title Two |1 |2001| |05|Serie One Title Three |4 |2011| |--|-----------------------|-------|----| This fancy join also comes close, but doesn't give the right result: select b.id, b.title, b.edition, b.year from books b inner join (select name, max(edition) as maxedition from books group by title) g on b.edition = g.maxedition where b.title like "serie one%" group by title; Using this I'm getting unique titles, but mostly old editions.

    Read the article

  • PHP Session variable isset(..)=1 after session_start()

    - by Nicsoft
    Hello! I guess I am not understanding the scope of session variables, or the session itself, in PHP, hence this question: This is my code if(!session_id()==""){ echo "Getting rid of session"."</br>"; session_destroy(); } echo "Before session_start(): ".isset($_SESSION["first_date_of_week"])."</br>"; session_start(); echo "After session_start(): ".isset($_SESSION["first_date_of_week"])." ".$_SESSION["first_date_of_week"]->format("Y-m-d")."</br>"; The output is: Before session_start(): After session_start(): 1 2011-01-09 How come that when doing the isset(..) on the session variable it is set directly after starting the session, even though I haven't even used it or set it yet? It does, however, still have the same value as before. Also, session_id()="" since the if-clause is never triggered. I never kill the session, how come it is set to ""? I.e. I refresh the page and expects the session to still be alive. Using the isset(..) function is then pretty useless testing if it has been set already... Thanks in advance! /Niklas

    Read the article

  • NullPointerException on Activity Testing Tutorial

    - by Bendik
    Hello, I am currently trying the activity testing tutorial (Found here), and have a problem. It seems that whenever I try to call something inside the UIThread, I get a java.lang.NullPointerException. public void testSpinnerUI() { mActivity.runOnUiThread( new Runnable() { public void run() { mSpinner.requestFocus(); } }); } This gives me: Incomplete: java.lang.NullPointerException and nothing else. I have tried this on two different samples now, with the same result. I tried with a try/catch clause around the mSpinner.requestFocus() call, and it seems that mSpinner is null inside the thread. I have set it properly up with the setUp() function found in the same sample, and a quick assertNotNull( mSpinner ) shows me that mSpinner is in fact not null after the setUp() function. What can be the cause of this? EDIT; ok, some more testing has been done. It seems that the application that is being tested resets between each test. This essentially makes me have to reinstantiate all variables between each test. Is this normal?

    Read the article

  • Conditional insert as a single database transaction in HSQLDB 1.8?

    - by Kevin Pauli
    I'm using a particular database table like a "Set" data structure, i.e., you can attempt to insert the same row several times, but it will only contain one instance. The primary key is a natural key. For example, I want the following series of operations to work fine, and result in only one row for Oklahoma: insert into states_visited (state_name) values ('Oklahoma'); insert into states_visited (state_name) values ('Texas'); insert into states_visited (state_name) values ('Oklahoma'); I am of course getting an error due to the duplicate primary key on subsequent inserts of the same value. Is there a way to make the insert conditional, so that these errors are not thrown? I.e. only do the the insert if the natural key does not already exist? I know I could do a where clause and a subquery to test for the row's existence first, but it seems that would be expensive. That's 2 physical operations for one logical "conditional insert" operation. Anything like this in SQL? FYI I am using HSQLDB 1.8

    Read the article

  • MySQL to PostreSQL and Named Scope

    - by Lowgain
    I've got a named scope for one of my models that works fine. The code is: named_scope :inbox_threads, lambda { |user| { :include => [:deletion_flags, :recipiences], :conditions => ["recipiences.user_id = ? AND deletion_flags.user_id IS NULL", user.id], :group => "msg_threads.id" }} This works fine on my local copy of the app with a MySQL database, but when I push my app to Heroku (which only uses PostgreSQL), I get the following error: ActiveRecord::StatementInvalid (PGError: ERROR: column "msg_threads.subject" must appear in the GROUP BY clause or be used in an aggregate function: SELECT "msg_threads"."id" AS t0_r0, "msg_threads"."subject" AS t0_r1, "msg_threads"."originator_id" AS t0_r2, "msg_thr eads"."created_at" AS t0_r3, "msg_threads"."updated_at" AS t0_r4, "msg_threads"."url_key" AS t0_r5, "deletion_flags"."id" AS t1_r0, "deletion_flags"."user_id" AS t1_r1, "deletion_flags"."msg_thread_id" AS t1_r2, "deletion_flags"."confirmed" AS t1_r3, "deletion_flags"."created_at" AS t1_r4, "deletion_flags"."updated_at" AS t1_r5, "recipiences"."id" AS t2_r0, "recipiences"."user_id" AS t2_r1, "recipiences"."msg_thread_id" AS t2_r2, "recipiences"."created_at" AS t2_r3, "recipien ces"."updated_at" AS t2_r4 FROM "msg_threads" LEFT OUTER JOIN "deletion_flags" ON deletion_flags.msg_thread_id = msg_threads.id LEFT OUTER JOIN "recipiences" ON recipiences.msg_thread_id = msg_threads.id WHERE (recipiences.user_id = 1 AND deletion_flags.user_id IS NULL) GROUP BY msg_threads.id) I'm not as familiar with the working of Postgres, so what would I need to add here to get this working? Thanks!

    Read the article

  • Most efficient way to LIMIT results in a JOIN?

    - by johnnietheblack
    I have a fairly simple one-to-many type join in a MySQL query. In this case, I'd like to LIMIT my results by the left table. For example, let's say I have an accounts table and a comments table, and I'd like to pull 100 rows from accounts and all the associated comments rows for each. Thy only way I can think to do this is with a sub-select in in the FROM clause instead of simply selecting FROM accounts. Here is my current idea: SELECT a.*, c.* FROM (SELECT * FROM accounts LIMIT 100) a LEFT JOIN `comments` c on c.account_id = a.id ORDER BY a.id However, whenever I need to do a sub-select of some sort, my intermediate level SQL knowledge feels like it's doing something wrong. Is there a more efficient, or faster, way to do this, or is this pretty good? By the way... This might be the absolute simplest way to do this, which I'm okay with as an answer. I'm simply trying to figure out if there IS another way to do this that could potentially compete with the above statement in terms of speed.

    Read the article

  • Learn Prolog Now! DCG Practice Example

    - by Timothy
    I have been progressing through Learn Prolog Now! as self-study and am now learning about Definite Clause Grammars. I am having some difficulty with one of the Practical Session's tasks. The task reads: The formal language anb2mc2mdn consists of all strings of the following form: an unbroken block of as followed by an unbroken block of bs followed by an unbroken block of cs followed by an unbroken block of ds, such that the a and d blocks are exactly the same length, and the c and d blocks are also exactly the same length and furthermore consist of an even number of cs and ds respectively. For example, ε, abbccd, and aaabbbbccccddd all belong to anb2mc2mdn. Write a DCG that generates this language. I am able to write rules that generate andn, b2mc2m, and even anb2m and c2mndn... but I can't seem to join all these rules into anb2mc2mdn. The following are my rules that can generate andn and b2mc2m. s1 --> []. s1 --> a,s1,d. a --> [a]. d --> [d]. s2 --> []. s2 --> c,c,s2,d,d. c --> [c]. d --> [d]. Is anb2mc2mdn really a CFG, and is it possible to write a DCG using only what was taught in the lesson (no additional arguments or code, etc)? If so, can anyone offer me some guidance how I can join these so that I can solve the given task?

    Read the article

  • :order does not work on :include

    - by SpyrosP
    Hello there, i'm wondering why this gives me an error : DiscoveredLocation.find_all_by_user_id(user.id, :include => [:boss_location, :monsters], :order => 'boss_location.location_index ASC') It seems as if it's trying to execute a really long query and i get an error like : Mysql::Error: Unknown column 'monsters_discovered_locations_join.boss_location_id' in 'on clause': SELECT `discovered_locations`.`id` AS t0_r0, `discovered_locations`.`user_id` AS t0_r1, `discovered_locations`.`boss_location_id` AS t0_r2, `discovered_locations`.`created_at` AS t0_r3, `discovered_locations`.`updated_at` AS t0_r4, `boss_locations`.`id` AS t1_r0, `boss_locations`.`name` AS t1_r1, `boss_locations`.`location_index` AS t1_r2, `boss_locations`.`min_level` AS t1_r3, `boss_locations`.`needed_gold_to_open` AS t1_r4, `boss_locations`.`created_at` AS t1_r5, `boss_locations`.`updated_at` AS t1_r6, `monsters`.`id` AS t2_r0, `monsters`.`name` AS t2_r1, `monsters`.`strength` AS t2_r2, `monsters`.`dexterity` AS t2_r3, `monsters`.`magic` AS t2_r4, `monsters`.`accuracy` AS t2_r5, `monsters`.`minGold` AS t2_r6, `monsters`.`maxGold` AS t2_r7, `monsters`.`hp` AS t2_r8, `monsters`.`level` AS t2_r9, `monsters`.`armor` AS t2_r10, `monsters`.`first_class` AS t2_r11, `monsters`.`weapon_id` AS t2_r12, `monsters`.`imageName` AS t2_r13, `monsters`.`monster_type` AS t2_r14, `monsters`.`boss_location_index` AS t2_r15, `monsters`.`boss_location_id` AS t2_r16, `monsters`.`created_at` AS t2_r17, `monsters`.`updated_at` AS t2_r18 FROM `discovered_locations` LEFT OUTER JOIN `boss_locations` ON `boss_locations`.id = `discovered_locations`.boss_location_id LEFT OUTER JOIN `boss_locations` monsters_discovered_locations_join ON (`discovered_locations`.`id` = `monsters_discovered_locations_join`.`boss_location_id`) LEFT OUTER JOIN `monsters` ON (`monsters`.`boss_location_id` = `monsters_discovered_locations_join`.`id`) WHERE (`discovered_locations`.`user_id` = 986759322) ORDER BY boss_location.location_index ASC The models associations are : class BossKill < ActiveRecord::Base belongs_to :user belongs_to :monster class DiscoveredLocation < ActiveRecord::Base belongs_to :user belongs_to :boss_location has_many :monsters, :through => :boss_location has_many :boss_kills, :through => :monsters class BossLocation < ActiveRecord::Base has_many :discovered_locations has_many :users, :through => :discovered_locations has_many :monsters Any ideas ?

    Read the article

  • Eliminate full table scan due to BETWEEN (and GROUP BY)

    - by Dave Jarvis
    Description According to the explain command, there is a range that is causing a query to perform a full table scan (160k rows). How do I keep the range condition and reduce the scanning? I expect the culprit to be: Y.YEAR BETWEEN 1900 AND 2009 AND Code Here is the code that has the range condition (the STATION_DISTRICT is likely superfluous). SELECT COUNT(1) as MEASUREMENTS, AVG(D.AMOUNT) as AMOUNT, Y.YEAR as YEAR, MAKEDATE(Y.YEAR,1) as AMOUNT_DATE FROM CITY C, STATION S, STATION_DISTRICT SD, YEAR_REF Y FORCE INDEX(YEAR_IDX), MONTH_REF M, DAILY D WHERE -- For a specific city ... -- C.ID = 10663 AND -- Find all the stations within a specific unit radius ... -- 6371.009 * SQRT( POW(RADIANS(C.LATITUDE_DECIMAL - S.LATITUDE_DECIMAL), 2) + (COS(RADIANS(C.LATITUDE_DECIMAL + S.LATITUDE_DECIMAL) / 2) * POW(RADIANS(C.LONGITUDE_DECIMAL - S.LONGITUDE_DECIMAL), 2)) ) <= 50 AND -- Get the station district identification for the matching station. -- S.STATION_DISTRICT_ID = SD.ID AND -- Gather all known years for that station ... -- Y.STATION_DISTRICT_ID = SD.ID AND -- The data before 1900 is shaky; insufficient after 2009. -- Y.YEAR BETWEEN 1900 AND 2009 AND -- Filtered by all known months ... -- M.YEAR_REF_ID = Y.ID AND -- Whittled down by category ... -- M.CATEGORY_ID = '003' AND -- Into the valid daily climate data. -- M.ID = D.MONTH_REF_ID AND D.DAILY_FLAG_ID <> 'M' GROUP BY Y.YEAR Update The SQL is performing a full table scan, which results in MySQL performing a "copy to tmp table", as shown here: +----+-------------+-------+--------+-----------------------------------+--------------+---------+-------------------------------+--------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+-----------------------------------+--------------+---------+-------------------------------+--------+-------------+ | 1 | SIMPLE | C | const | PRIMARY | PRIMARY | 4 | const | 1 | | | 1 | SIMPLE | Y | range | YEAR_IDX | YEAR_IDX | 4 | NULL | 160422 | Using where | | 1 | SIMPLE | SD | eq_ref | PRIMARY | PRIMARY | 4 | climate.Y.STATION_DISTRICT_ID | 1 | Using index | | 1 | SIMPLE | S | eq_ref | PRIMARY | PRIMARY | 4 | climate.SD.ID | 1 | Using where | | 1 | SIMPLE | M | ref | PRIMARY,YEAR_REF_IDX,CATEGORY_IDX | YEAR_REF_IDX | 8 | climate.Y.ID | 54 | Using where | | 1 | SIMPLE | D | ref | INDEX | INDEX | 8 | climate.M.ID | 11 | Using where | +----+-------------+-------+--------+-----------------------------------+--------------+---------+-------------------------------+--------+-------------+ Related http://dev.mysql.com/doc/refman/5.0/en/how-to-avoid-table-scan.html http://dev.mysql.com/doc/refman/5.0/en/where-optimizations.html http://stackoverflow.com/questions/557425/optimize-sql-that-uses-between-clause Thank you!

    Read the article

  • Simple POSIX threads question

    - by Andy
    Hi, I have this POSIX thread: void subthread(void) { while(!quit_thread) { // do something ... // don't waste cpu cycles if(!quit_thread) usleep(500); } // free resources ... // tell main thread we're done quit_thread = FALSE; } Now I want to terminate subthread() from my main thread. I've tried the following: quit_thread = TRUE; // wait until subthread() has cleaned its resources while(quit_thread); But it does not work! The while() clause does never exit although my subthread clearly sets quit_thread to FALSE after having freed its resources! If I modify my shutdown code like this: quit_thread = TRUE; // wait until subthread() has cleaned its resources while(quit_thread) usleep(10); Then everything is working fine! Could someone explain to me why the first solution does not work and why the version with usleep(10) suddenly works? I know that this is not a pretty solution. I could use semaphores/signals for this but I'd like to learn something about multithreading, so I'd like to know why my first solution doesn't work. Thanks!

    Read the article

  • Mysql slow query: INNER JOIN + ORDER BY causes filesort

    - by Alexander
    Hello! I'm trying to optimize this query: SELECT `posts`.* FROM `posts` INNER JOIN `posts_tags` ON `posts`.id = `posts_tags`.post_id WHERE (((`posts_tags`.tag_id = 1))) ORDER BY posts.created_at DESC; The size of tables is 38k rows, and 31k and mysql uses "filesort" so it gets pretty slow. I tried to use different indexes, no luck. CREATE TABLE `posts` ( `id` int(11) NOT NULL auto_increment, `created_at` datetime default NULL, PRIMARY KEY (`id`), KEY `index_posts_on_created_at` (`created_at`), KEY `for_tags` (`trashed`,`published`,`clan_private`,`created_at`) ) ENGINE=InnoDB AUTO_INCREMENT=44390 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci CREATE TABLE `posts_tags` ( `id` int(11) NOT NULL auto_increment, `post_id` int(11) default NULL, `tag_id` int(11) default NULL, `created_at` datetime default NULL, `updated_at` datetime default NULL, PRIMARY KEY (`id`), KEY `index_posts_tags_on_post_id_and_tag_id` (`post_id`,`tag_id`) ) ENGINE=InnoDB AUTO_INCREMENT=63175 DEFAULT CHARSET=utf8 +----+-------------+------------+--------+--------------------------+--------------------------+---------+---------------------+-------+-----------------------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+------------+--------+--------------------------+--------------------------+---------+---------------------+-------+-----------------------------------------------------------+ | 1 | SIMPLE | posts_tags | index | index_post_id_and_tag_id | index_post_id_and_tag_id | 10 | NULL | 24159 | Using where; Using index; Using temporary; Using filesort | | 1 | SIMPLE | posts | eq_ref | PRIMARY | PRIMARY | 4 | .posts_tags.post_id | 1 | | +----+-------------+------------+--------+--------------------------+--------------------------+---------+---------------------+-------+-----------------------------------------------------------+ 2 rows in set (0.00 sec) What kind of index I need to define to avoid mysql using filesort? Is it possible when order field is not in where clause?

    Read the article

  • How do I strip multiple (optional) parts of a SQL string using .NET Regular Expressions?

    - by Luc
    I've been working on this for a few hours now and can't find any help on it. Basically, I'm trying to strip a SQL string into various parts (fields, from, where, having, groupBy, orderBy). I refuse to believe that I'm the first person to ever try to do this, so I'd like to ask for some advise from the StackOverflow community. :) To understand what I need, assume the following SQL string: select * from table1 inner join table2 on table1.id = table2.id where field1 = 'sam' having table1.field3 > 0 group by table1.field4 order by table1.field5 I created a regular expression to group the parts accordingly: select\s+(?<fields>.+)\s+from\s+(?<from>.+)\s+where\s+(?<where>.+)\s+having\s+(?<having>.+)\s+group\sby\s+(?<groupby>.+)\s+order\sby\s+(?<orderby>.+) This gives me the following results: fields => * from => table1 inner join table2 on table1.id = table2.id where => field1 = 'sam' having => table1.field3 > 0 groupby => table1.field4 orderby => table1.field5 The problem that I'm faced with is that if any part of the SQL string is missing after the 'from' clause, the regular expression doesn't match. To fix that, I've tried putting each optional part in it's own (...)? group but that doesn't work. It simply put all the optional parts (where, having, groupBy, and orderBy) into the 'from' group. Any ideas?

    Read the article

  • Generic that takes only numeric types (int double etc)?

    - by brandon
    In a program I'm working on, I need to write a function to take any numeric type (int, short, long etc) and shove it in to a byte array at a specific offset. There exists a Bitconverter.GetBytes() method that takes the numeric type and returns it as a byte array, and this method only takes numeric types. So far I have: private void AddToByteArray<T>(byte[] destination, int offset, T toAdd) where T : struct { Buffer.BlockCopy(BitConverter.GetBytes(toAdd), 0, destination, offset, sizeof(toAdd)); } So basically my goal is that, for example, a call to AddToByteArray(array, 3, (short)10) would take 10 and store it in the 4th slot of array. The explicit cast exists because I know exactly how many bytes I want it to take up. There are cases where I would want a number that is small enough to be a short to really take up 4 bytes. On the flip side, there are times when I want an int to be crunched down to just a single byte. I'm doing this to create a custom network packet, if that makes any ideas pop in to your heads. If the where clause of a generic supported something like "where T : int || long || etc" I would be ok. (And no need to explain why they don't support that, the reason is fairly obvious) Any help would be greatly appreciated! Edit: I realize that I could just do a bunch of overloads, one for each type I want to support... but I'm asking this question because I want to avoid precisely that :)

    Read the article

  • a reusable query with modifications?

    - by fusion
    i'm using this mysql query alongwith php to search for multiple keywords: $query = "SELECT cQuotes, vAuthor, cArabic, vReference FROM ".$table." WHERE ("; $countFields = count($arrayFields); while ($a < $countFields) { while ($b < $countSearch) { $query = $query."$arrayFields[$a] LIKE '%$arraySearch[$b]%'"; $b++; if ($b < $countSearch) { $query = $query." AND "; } } $b = 0; $a++; if ($a < $countFields) { $query = $query.") OR ("; } } $query = $query.")"; $result = mysql_query($query, $conn) i'd like to reuse this query with a few modifications to it (for instance, the WHERE clause remains the same, while i query the number of rows using COUNT), but it doesn't seem practical to repeat the code again for a few additions. any suggestions?

    Read the article

  • Sub Query making Query slow.

    - by Muhammad Kashif Nadeem
    Please copy and paste following script. DECLARE @MainTable TABLE(MainTablePkId int) INSERT INTO @MainTable SELECT 1 INSERT INTO @MainTable SELECT 2 DECLARE @SomeTable TABLE(SomeIdPk int, MainTablePkId int, ViewedTime1 datetime) INSERT INTO @SomeTable SELECT 1, 1, DATEADD(dd, -10, getdate()) INSERT INTO @SomeTable SELECT 2, 1, DATEADD(dd, -9, getdate()) INSERT INTO @SomeTable SELECT 3, 2, DATEADD(dd, -6, getdate()) DECLARE @SomeTableDetail TABLE(DetailIdPk int, SomeIdPk int, Viewed INT, ViewedTimeDetail datetime) INSERT INTO @SomeTableDetail SELECT 1, 1, 1, DATEADD(dd, -7, getdate()) INSERT INTO @SomeTableDetail SELECT 2, 2, NULL, DATEADD(dd, -6, getdate()) INSERT INTO @SomeTableDetail SELECT 3, 2, 2, DATEADD(dd, -8, getdate()) INSERT INTO @SomeTableDetail SELECT 4, 3, 1, DATEADD(dd, -6, getdate()) SELECT m.MainTablePkId, (SELECT COUNT(Viewed) FROM @SomeTableDetail), (SELECT TOP 1 s2.ViewedTimeDetail FROM @SomeTableDetail s2 INNER JOIN @SomeTable s1 ON s2.SomeIdPk = s1.SomeIdPk WHERE s1.MainTablePkId = m.MainTablePkId) FROM @MainTable m Above given script is just sample. I have long list of columns in SELECT and around 12+ columns in Sub Query. In my From clause there are around 8 tables. To fetch 2000 records full query take 21 seconds and if I remove Subquiries it just take 4 seconds. I have tried to optimize query using 'Database Engine Tuning Advisor' and on adding new advised indexes and statistics but these changes make query time even bad. Note: As I have mentioned that this is test data to explain my question the real data has lot of tables joins columns but without Sub-Query the results us fine. Any help thanks.

    Read the article

  • Is this method of static file serving safe in node.js? (potential security hole?)

    - by MikeC8
    I want to create the simplest node.js server to serve static files. Here's what I came up with: fs = require('fs'); server = require('http').createServer(function(req, res) { res.end(fs.readFileSync(__dirname + '/public/' + req.url)); }); server.listen(8080); Clearly this would map http://localhost:8080/index.html to project_dir/public/index.html, and similarly so for all other files. My one concern is that someone could abuse this to access files outside of project_dir/public. Something like this, for example: http://localhost:8080/../../sensitive_file.txt I tried this a little bit, and it wasn't working. But, it seems like my browser was removing the ".." itself. Which leads me to believe that someone could abuse my poor little node.js server. I know there are npm packages that do static file serving. But I'm actually curious to write my own here. So my questions are: Is this safe? If so, why? If not, why not? And, if further, if not, what is the "right" way to do this? My one constraint is I don't want to have to have an if clause for each possible file, I want the server to serve whatever files I throw in a directory.

    Read the article

  • Using the JPA Criteria API, can you do a fetch join that results in only one join?

    - by Shaun
    Using JPA 2.0. It seems that by default (no explicit fetch), @OneToOne(fetch = FetchType.EAGER) fields are fetched in 1 + N queries, where N is the number of results containing an Entity that defines the relationship to a distinct related entity. Using the Criteria API, I might try to avoid that as follows: CriteriaBuilder builder = entityManager.getCriteriaBuilder(); CriteriaQuery<MyEntity> query = builder.createQuery(MyEntity.class); Root<MyEntity> root = query.from(MyEntity.class); Join<MyEntity, RelatedEntity> join = root.join("relatedEntity"); root.fetch("relatedEntity"); query.select(root).where(builder.equals(join.get("id"), 3)); The above should ideally be equivalent to the following: SELECT m FROM MyEntity m JOIN FETCH myEntity.relatedEntity r WHERE r.id = 3 However, the criteria query results in the root table needlessly being joined to the related entity table twice; once for the fetch, and once for the where predicate. The resulting SQL looks something like this: SELECT myentity.id, myentity.attribute, relatedentity2.id, relatedentity2.attribute FROM my_entity myentity INNER JOIN related_entity relatedentity1 ON myentity.related_id = relatedentity1.id INNER JOIN related_entity relatedentity2 ON myentity.related_id = relatedentity2.id WHERE relatedentity1.id = 3 Alas, if I only do the fetch, then I don't have an expression to use in the where clause. Am I missing something, or is this a limitation of the Criteria API? If it's the latter, is this being remedied in JPA 2.1 or are there any vendor-specific enhancements? Otherwise, it seems better to just give up compile-time type checking (I realize my example doesn't use the metamodel) and use dynamic JPQL TypedQueries.

    Read the article

  • Suggestion on Database structure for relational data

    - by miccet
    Hi there. I've been wrestling with this problem for quite a while now and the automatic mails with 'Slow Query' warnings are still popping in. Basically, I have Blogs with a corresponding table as well as a table that keeps track of how many times each Blog has been viewed. This last table has a huge amount of records since this page is relatively high traffic and it logs every hit as an individual row. I have tried with indexes on the fields that are included in the WHERE clause, but it doesn't seem to help. I have also tried to clean the table each week by removing old ( 1.weeks) records. SO, I'm asking you guys, how would you solve this? The query that I know is causing the slowness is generated by Rails and looks like this: SELECT count(*) AS count_all FROM blog_views WHERE (created_at >= '2010-01-01 00:00:01' AND blog_id = 1); The tables have the following structures: CREATE TABLE IF NOT EXISTS 'blogs' ( 'id' int(11) NOT NULL auto_increment, 'name' varchar(255) default NULL, 'perma_name' varchar(255) default NULL, 'author_id' int(11) default NULL, 'created_at' datetime default NULL, 'updated_at' datetime default NULL, 'blog_picture_id' int(11) default NULL, 'blog_picture2_id' int(11) default NULL, 'page_id' int(11) default NULL, 'blog_picture3_id' int(11) default NULL, 'active' tinyint(1) default '1', PRIMARY KEY ('id'), KEY 'index_blogs_on_author_id' ('author_id') ) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ; And CREATE TABLE IF NOT EXISTS 'blog_views' ( 'id' int(11) NOT NULL auto_increment, 'blog_id' int(11) default NULL, 'ip' varchar(255) default NULL, 'created_at' datetime default NULL, 'updated_at' datetime default NULL, PRIMARY KEY ('id'), KEY 'index_blog_views_on_blog_id' ('blog_id'), KEY 'created_at' ('created_at') ) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;

    Read the article

  • Laravel4: Checking many-to-many relationship attribute even when it does not exist

    - by Simo A.
    This is my first time with Laravel and also Stackoverflow... I am developing a simple course management system. The main objects are User and Course, with a many-to-many relationship between them. The pivot table has an additional attribute, participant_role, which defines whether the user is a student or an instructor within that particular course. class Course extends Eloquent { public function users() { return $this->belongsToMany('User')->withPivot('participant_role')->withTimestamps(); } } However, there is an additional role, system admin, which can be defined on the User object. And this brings me mucho headache. In my blade view I have the following: @if ($course->pivot->participant_role == 'instructor') { // do something here... } This works fine when the user has been assigned to that particular $course and there is an entry for this user-course combination in the pivot table. However, the problem is the system administrator, who also should be able to access course details. The if-clause above gives Trying to get property of non-object error, apparently because there is no entry in the pivot table for system administrator (as the role is defined within the User object). I could probably solve the problem by using some off-the-shelf bundle for handling role-based permissions. Or I could (but don't want to) do something like this with two internal if-clauses: if (!empty($course->pivot)) { if ($course->pivot->participant_role == 'instructor') { // do something... } } Other options (suggested in partially similar entries in Stackoverflow) would include 1) reading all the pivot table entries to an array, and use in_array to check if a role exists, or even 2) SQL left join to do this on database level. However, ultimately I am looking for a compact one-line solution? Can I do anything similar to this, which unfortunately does not seem to work? if (! empty ($course->pivot->participant_role == 'instructor') ) { // do something... } The shorter the answer, the better :-). Thanks a lot!

    Read the article

  • Can foreground threads be aborted on application shutdown in C#.Net?

    - by Cartman
    I inherited a c# winforms app (.NET 2.0) which creates a thread upon startup in a singleton class. This thread handles messages from a messaging topic (Tibco EMS). When the app is shutdown, the thread doesn't remain the the background? How is this possible? Is there something else happening that can abort this thread? Code snippet: public class Startup { public static void main(string [] args) { MySingletonClass.Instance.Init(); // do other things below Application.Run(new MainForm()); } public class MySingletonClass { // singleton code //.. //.. private Thread t; public void Init() { t = new Thread(new ThreadStart(poll)); } private void poll() { while(true} { // listen for messages and process but there is no break clause // exceptions are also handled within to ensure control doesnt go out } } Pls. don't write to tell me this is bad code. I know it and i was going to refactor it when i realised that the app actually shutdowns correctly inspite of this aberration. So i want to understand how this is possible. Thanks for your help

    Read the article

  • How to add additional condition to the JOIN generated by include?

    - by KandadaBoggu
    I want to add additional criteria to the LEFT OUTER JOIN generated by the :include option in ActiveRecord finder. class Post has_many :comments end class Comment belongs_to :post has_many :comment_votes end class CommentVote belongs_to :comment end Now lets say I want to find last 10 posts with their associated comments and the up comment votes. Post.find.all(:limit => 10, :order => "created_at DESC", :include => [{:comments => :comment_votes]) I cant add the condition to check for up votes as it will ignore the posts without the up votes. So the condition has to go the ON clause of the JOIN generated for the comment_votes. I am wishing for a syntax such as: Post.find.all(:limit => 10, :order => "created_at DESC", :include => [{:comments => [:comment_votes, :on => "comment_votes.vote > 0"]) Have you faced such problems before? Did you managed to solve the problem using the current finder? I hope to hear some interesting ideas from the community. PS: I can write a join SQL to get the expected result and stitch the results together. I want to make sure there is no other alternative before going down that path.

    Read the article

  • Why does this php/ajax query fail?

    - by Ashley Brown
    I'm ajaxing over to this php file. $a = 'old'; $b = 'new'; if ($_POST['info-type'] == $a || $b) { $info = $_POST['info-type']; $query = "SELECT * FROM `tld` WHERE type = '".$var."'"; } $query = "SELECT * FROM `tld` "; $result = mysqli_query($link,$query); while($row = mysqli_fetch_assoc($result)) { echo '<div>'.$row['something'].'</div>'; } The data posted is either 'all' 'new' or 'old'. If i send the data as either new or old, the script works and outputs as expected. If the posted data is neither new or old but all instead, it fails and don't show any errors or respond anything back. (I've monitored via dev tools aswell) So, I tried this if ($_POST['info-type'] == $a || $b) { $info = $_POST['info-type']; $var = "SELECT * FROM `tld` WHERE type = '".$var."'"; } elseif ($_POST['info-type'] == 'all'){ $query = "SELECT * FROM `tld` "; } But the script still fails. If i fully remove the IF statements and use the query without the WHERE clause like it is after the elseif, it works?

    Read the article

  • Using jquery to change checkbox status

    - by Jeff
    Hi everyone! I have a list of items that have checkboxes associated with them, and the items are beneath a list header, which also has a checkbox(for db purposes only) which is actually hidden from view. I need to make it so that if any of the checkboxes beneath the header is checked, then the header checkbox is checked as well. BUT I also need to make it so that if all of the checkboxes are unchecked, then the header one is unchecked...how hard is this going to be? This is how I have it setup now: if($('.childCheckBox').is(":checked")){ $('#parentBox').attr('checked', true); } Now I am thinking that if I were to do something where I add an else if clause: else if($('.proBox2').is(not)(":checked"){ alert("uncheck parent"); } But I don't know the correct syntax for is-not, or isn't, or even if there is anything that will do that. Are there any thoughts out there? I need the box to check if one is selected and uncheck if none are selected. Thanks!!

    Read the article

< Previous Page | 326 327 328 329 330 331 332 333 334 335 336 337  | Next Page >