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  • Can I get away with this or is it just too crude and unpractical ?

    - by The_AlienCoder
    I spent the whole of last night searching for a free AspNet web chat control that I could simply drag into my website. Well the search was in vain as I could not find a control that matched my needs i.e List of users, 1 to 1 chat, Ability to kick out users.. In the end I decided to create my own control from scractch. Although it works well on my machine Im concerned that It maybe a little crude and unpractical on a shared hosting enviroment. Basically this is what I did : Created an sql database that stores the chat messages. Wrote the stored procedures and and included a statement that clears old messages Then the 'crude' part : Dragged an update panel and timer control on my page Dragged a Repeater databound to the chat messages table inside the update panel Dragged another update panel and inside it put a textbox and a button Configured the timer control to tick every 5 seconds. ..and then I made it all work like this In the timer tick event I 'refreshed' the messages display by invoking Databind() on my repeater i.e protected void Timer1_Tick(object sender, EventArgs e) { MyRepeater.DataBind(); } Then in my send button click event protected void btnSend_Click(object sender, EventArgs e) { MyDataLayer.InsertMessage(Message, Sender, CurrTime); } Well It works well on my machine and Ive got the other functionalities(users list, kick out user..) to work by simply creating more tables. But like I said it seems a little crude to me. so I need a proffesional opinion. Should I run with this or try another Approach ?

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  • Mysql dropping inserts with triggers

    - by user2891127
    Using mysql 5.5. I have two tables. One has a whitelist of hashes. When I insert a new row into the other table, I want to first compare the hash in the insert statement to the whitelist. If it's in the whitelist, I don't want to do the insert (less data to plow through later). The inserts are generated from another program and are text files with sql statements. I've been playing with triggers, and almost have it working: BEGIN IF (select count(md5hash) from whitelist where md5hash=new.md5hash) 0 THEN SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'Already Whitelisted'; END IF; END But there's a problem. The Signal throwing up the error stops the import. I want to skip that line, not stop the whole import. Some searching didn't find any way to silently skip the import. My next idea was to create a duplicate table definition, and redirect the insert to that dup table. But the old and new don't seem to apply to table names. Other then adding an ignore column to my table then doing a mass drop based on that column after the import, is there any way to achieve my goal?

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  • Data mixing SQL Server

    - by Pythonizo
    I have three tables and a range of two dates: Services ServicesClients ServicesClientsDone @StartDate @EndDate Services: ID | Name 1 | Supervisor 2 | Monitor 3 | Manufacturer ServicesClients: IDServiceClient | IDClient | IDService 1 | 1 | 1 2 | 1 | 2 3 | 2 | 2 4 | 2 | 3 ServicesClientsDone: IDServiceClient | Period 1 | 201208 3 | 201210 Period = YYYYMM I need to insert into ServicesClientsDone the months range from @StartDate up @EndDate. I have also a temporary table (#Periods) with the following list: Period 201208 201209 201210 The query I need is to give me back the following list: IDServiceClient | Period 1 | 201209 1 | 201210 2 | 201208 2 | 201209 2 | 201210 3 | 201208 3 | 201209 4 | 201208 4 | 201209 4 | 201210 Which are client services but the ranks of the temporary table, not those who are already inserted This is what i have: Table periods: DECLARE @i int DECLARE @mm int DECLARE @yyyy int, DECLARE @StartDate datetime DECLARE @EndDate datetime set @EndDate = (SELECT GETDATE()) set @StartDate = (SELECT DATEADD(MONTH, -3,GETDATE())) CREATE TABLE #Periods (Period int) set @i = 0 WHILE @i <= DATEDIFF(MONTH, @StartDate , @EndDate ) BEGIN SET @mm= DATEPART(MONTH, DATEADD(MONTH, @i, @FechaInicio)) SET @yyyy= DATEPART(YEAR, DATEADD(MONTH, @i, @FechaInicio)) INSERT INTO #Periods (Period) VALUES (CAST(@yyyy as varchar(4)) + RIGHT('00'+CONVERT(varchar(6), @mm), 2)) SET @i = @i + 1; END Relation between ServicesClients and Services: SELECT s.Name, sc.IDClient FROM Services JOIN ServicesClients AS sc ON sc.IDService = s.ID Services already done and when: SELECT s.Name, scd.Period FROM Services JOIN ServicesClients AS sc ON sc.IDService = s.ID JOIN ServicesClientsDone AS scd ON scd.IDServiceClient = sc.IDServiceClient

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  • How to optimize this simple function which translates input bits into words?

    - by psihodelia
    I have written a function which reads an input buffer of bytes and produces an output buffer of words where every word can be either 0x0081 for each ON bit of the input buffer or 0x007F for each OFF bit. The length of the input buffer is given. Both arrays have enough physical place. I also have about 2Kbyte free RAM which I can use for lookup tables or so. Now, I found that this function is my bottleneck in a real time application. It will be called very frequently. Can you please suggest a way how to optimize this function? I see one possibility could be to use only one buffer and do in-place substitution. void inline BitsToWords(int8 *pc_BufIn, int16 *pw_BufOut, int32 BufInLen) { int32 i,j,z=0; for(i=0; i<BufInLen; i++) { for(j=0; j<8; j++, z++) { pw_BufOut[z] = ( ((pc_BufIn[i] >> (7-j))&0x01) == 1? 0x0081: 0x007f ); } } } Please do not offer any compiler specific or CPU/Hardware specific optimization, because it is a multi-platform project.

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  • MYSQL how to sum rows with same key, then delete the duplicate rows

    - by Bhante-S
    What I have: key data 1      22 1       5 2       6 3       1 3      -3 What I want: key data 1      27 2       6 3      -2 I don’t mind doing this with two or more queries, esp. if they are simple--makes for easier maintenance. Also the tables are fairly small (<2,000 records). The ‘key’ field is indexed and allows duplicates. Muchas Gracias

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  • Stored Procedure, 'incorrect syntax error'

    - by jacksonSD
    Attempting to figure out sp's, and I'm getting this error: "Msg 156, Level 15, State 1, Line 5 Incorrect syntax near the keyword 'Procedure'." the error seems to be on the if, but I can drop other existing tables with stored procedures the exact same way so I'm not clear on why this isn't working. can anyone shed some light? Begin Set nocount on Begin Try Create Procedure uspRecycle as if OBJECT_ID('Recycle') is not null Drop Table Recycle create table Recycle (RecycleID integer constraint PK_integer primary key, RecycleType nchar(10) not null, RecycleDescription nvarchar(100) null) insert into Recycle (RecycleID,RecycleType,RecycleDescription) values ('1','Compost','Product is compostable, instructions included in packaging') insert into Recycle (RecycleID,RecycleType,RecycleDescription) values ('2','Return','Product is returnable to company for 100% reuse') insert into Recycle (RecycleID,RecycleType,RecycleDescription) values ('3','Scrap','Product is returnable and will be reclaimed and reprocessed') insert into Recycle (RecycleID,RecycleType,RecycleDescription) values ('4','None','Product is not recycleable') End Try Begin Catch DECLARE @ErrMsg nvarchar(4000); SELECT @ErrMsg = ERROR_MESSAGE(); Throw 50001, @ErrMsg, 1; End Catch -- checking to see if table exists and is loaded: If (Select count(*) from Recycle) >1 begin Print 'Recycle table created and loaded '; Print getdate() End set nocount off End

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  • How to emulate a BEFORE DELETE trigger in SQL Server 2005

    - by Mark
    Let's say I have three tables, [ONE], [ONE_TWO], and [TWO]. [ONE_TWO] is a many-to-many join table with only [ONE_ID and [TWO_ID] columns. There are foreign keys set up to link [ONE] to [ONE_TWO] and [TWO] to [ONE_TWO]. The FKs use the ON DELETE CASCADE option so that if either a [ONE] or [TWO] record is deleted, the associated [ONE_TWO] records will be automatically deleted as well. I want to have a trigger on the [TWO] table such that when a [TWO] record is deleted, it executes a stored procedure that takes a [ONE_ID] as a parameter, passing the [ONE_ID] values that were linked to the [TWO_ID] before the delete occurred: DECLARE @Statement NVARCHAR(max) SET @Statement = '' SELECT @Statement = @Statement + N'EXEC [MyProc] ''' + CAST([one_two].[one_id] AS VARCHAR(36)) + '''; ' FROM deleted JOIN [one_two] ON deleted.[two_id] = [one_two].[two_id] EXEC (@Statement) Clearly, I need a BEFORE DELETE trigger, but there is no such thing in SQL Server 2005. I can't use an INSTEAD OF trigger because of the cascading FK. I get the impression that if I use a FOR DELETE trigger, when I join [deleted] to [ONE_TWO] to find the list of [ONE_ID] values, the FK cascade will have already deleted the associated [ONE_TWO] records so I will never find any [ONE_ID] values. Is this true? If so, how can I achieve my objective? I'm thinking that I'd need to change the FK joining [TWO] to [ONE_TWO] to not use cascades and to do the delete from [ONE_TWO] manually in the trigger just before I manually delete the [TWO] records. But I'd rather not go through all that if there is a simpler way.

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  • Is it possible to aggregate over differing where clauses?

    - by BenAlabaster
    Is it possible to calculate multiple aggregates based on differing where clauses? For instance: Let's say I have two tables, one for Invoice and one for InvoiceLineItems. The invoice table has a total field for the invoice total, and each of the invoice line item records in the InvoiceLineItems table contains a field that denotes whether the line item is discountable or not. I want three sum totals, one where Discountable = 0 and one where Discountable = 1 and one where Discountable is irrelevant. Such that my output would be: InvoiceNumber Total DiscountableTotal NonDiscountableTotal ------------- ----- ----------------- -------------------- 1 53.27 27.27 16.00 2 38.94 4.76 34.18 3... The only way I've found so far is by using something like: Select i.InvoiceNumber, i.Total, t0.Total As DiscountableTotal, t1.Total As NonDiscountableTotal From Invoices i Left Join ( Select InvoiceNumber, Sum(Amount), From InvoiceLineItems Where Discountable = 0 Group By InvoiceNumber ) As t0 On i.InvoiceNumber = t0.InvoiceNumber Left Join ( Select InvoiceNumber, Sum(Amount) From InvoiceLineItems Where Discountable = 1 Group By InvoiceNumber ) As t1 On i.InvoiceNumber = t1.InvoiceNumber This seems somewhat cumbersome, it would be nice if I could do something like: Select InvoiceNumber, Sum(Amount) Where Discountable = 1 As Discountable Sum(Amount) Where Discountable = 0 As NonDiscountable Group By InvoiceNumber I realize that SQL is completely invalid, but it logically portrays what I'm trying to do... TIA P.S. I need this to run on a SQL Server 2000 instance, but I am also interested (for future reference) if/how I would achieve this on SQL Server 2005/2008.

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  • How to synchronize two (or n) replication processes for SQL Server databases?

    - by Yauheni Sivukha
    There are two master databases and two read-only copies updated by standard transactional replication. It is needed to map some entity from both read-only databases, lets say that A databases contains orders and B databases contains lines. The problem is that replication to one database can lag behind replication of second database, and at the moment of mapping R-databases will have inconsistent data. For example. We stored 2 orders with lines at 19:00 and 19:03. Mapping process started at 19:05, but to the moment of mapping A database replication processed all changes up to 19:03, but B database replication processed only changes up to 19:00. After mapping we will have order entity with order as of 19:03 and lines as of 19:00. The troubles are guaranteed:) In my particular case both databases have temporal model, so it is possible to fetch data for every time slice, but the problem is to identify time of latest replication. Question: How to synchronize replication processes for several databases to avoid situation described above? Or, in other words, how to compare last time of replication in each database? UPD: The only way I see to synchronize is to continuously write timestamps into service tables in each database and to check these timestamps on replicated servers. Is that acceptable solution?

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  • custom sorting or ordering a table without resorting the whole shebang

    - by fuugus
    for ten years we've been using the same custom sorting on our tables, i'm wondering if there is another solution which involves fewer updates, especially since today we'd like to have a replication/publication date and would'nt like to have our replication replicate unnecessary entries. i had a look into nested sets, but it does'nt seem to do the job for us. base table: id | a_sort ---+------- 1 10 2 20 3 30 after inserting insert into table (a_sort) values(15) an entry at the second position. id | a_sort ---+------- 1 10 2 20 3 30 4 15 ordering the table with select * from table order by a_sort and resorting all the a_sort entries, updating at least id=(2,3,4) will of course produce the desired output id | a_sort ---+------- 1 10 4 20 2 30 3 40 the column names, the column count, datatypes, a possible join, possible triggers or the way the resorting is done is/are irrelevant to the problem. also we've found some pretty neat ways to do this task fast. only; how the heck can we reduce the updates in the db to 1 or 2 max. seems like an awfully common problem. the captain obvious in me thougth once "use an a_sort float(53), insert using a fixed value of ordervaluefirstentry+abs(ordervaluefirstentry-ordervaluenextentry)/2".. but this would only allow around 1040 "in between" entries - so never resorting seems a bit problematic ;)

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  • HTML prevent line break (between two table tags)

    - by arik-so
    Hello, I have following code: <table> <tr> <td>Table 1</td> </tr> </table> <table> <tr> <td>Table 2</td> </tr> </table> Very unfortunately, a line break is inserted between these two tables. I have tried putting them both in a single span and setting the whitespace to nowrap, but at no avail. Please, could you tell me how I can simply put these elements in a single row, without setting the float attribute in CSS and without surrounding each table with a <td> {table} </td> and then putting this in a table row. Thanks a lot in advance. I have asked Google, but it just wouldn't say anything ^^ StackOverflow remained silent so far, too

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  • How to handle ids and polymorphic associations in views if compound keys are not supported?

    - by duncan
    I have a Movie plan table: movie_plans (id, description) Each plan has items, which describe a sequence of movies and the duration in minutes: movie_plan_items (id, movie_plan_id, movie_id, start_minutes, end_minutes) A specific instance of that plan happens in: movie_schedules (id, movie_plan_id, start_at) However the schedule items can be calculated from the movie_plan_items and the schedule start time by adding the minutes create view movie_schedule_items as select CONCAT(p.id, '-', s.id) as id, s.id as movie_schedule_id, p.id as movie_plan_item_id, p.movie_id, p.movie_plan_id, (s.start_at + INTERVAL p.start_minutes MINUTE) as start_at, (s.start_at + INTERVAL p.end_minutes MINUTE) as end_at from movie_plan_items p, movie_schedules s where s.movie_plan_id=p.movie_plan_id; I have a model over this view (readonly), it works ok, except that the id is right now a string. I now want to add a polymorphic property (like comments) to various of the previous tables. Therefore for movie_schedule_items I need a unique and persistent numeric id. I have the following dilemma: I could avoid the id and have movie_schedule_items just use the movie_plan_id and movie_schedule_id as a compound key, as it should. But Rails sucks in this regard. I could create an id using String#hash or a md5, thus making it slower or collision prone (and IIRC String#hash is no longer persistent across processes in Ruby 1.9) Any ideas on how to handle this situation?

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  • SQL: find entries in 1:n relation that don't comply with condition spanning multiple rows

    - by milianw
    I'm trying to optimize SQL queries in Akonadi and came across the following problem that is apparently not easy to solve with SQL, at least for me: Assume the following table structure (should work in SQLite, PostgreSQL, MySQL): CREATE TABLE a ( a_id INT PRIMARY KEY ); INSERT INTO a (a_id) VALUES (1), (2), (3), (4); CREATE TABLE b ( b_id INT PRIMARY KEY, a_id INT, name VARCHAR(255) NOT NULL ); INSERT INTO b (b_id, a_id, name) VALUES (1, 1, 'foo'), (2, 1, 'bar'), (3, 1, 'asdf'), (4, 2, 'foo'), (5, 2, 'bar'), (6, 3, 'foo'); Now my problem is to find entries in a that are missing name entries in table b. E.g. I need to make sure each entry in a has at least the name entries "foo" and "bar" in table b. Hence the query should return something similar to: a_id = 3 is missing name "bar" a_id = 4 is missing name "foo" and "bar" Since both tables are potentially huge in Akonadi, performance is of utmost importance. One solution in MySQL would be: SELECT a.a_id, CONCAT('|', GROUP_CONCAT(name ORDER BY NAME ASC SEPARATOR '|'), '|') as names FROM a LEFT JOIN b USING( a_id ) GROUP BY a.a_id HAVING names IS NULL OR names NOT LIKE '%|bar|foo|%'; I have yet to measure the performance tomorrow, but severly doubt it's any fast for tens of thousand of entries in a and thrice as many in b. Furthermore we want to support SQLite and PostgreSQL where to my knowledge the GROUP_CONCAT function is not available. Thanks, good night.

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  • SQL code to display counts() of value retrieved from another column

    - by Doctor Trout
    I have three tables (these are the relevant columns): Table1 bookingid, person, role Table2 bookingid, projectid Table3 projectid, project, numberofrole1, numberofrole2 Table1.role can take two values: "role1" or "role2". What I want to do is to show which projects don't have the correct number of roles in Table1. The number of roles there there should be for each role is in Table3. For example, if Table1 contains these three rows: bookingid, person, role 7, Tim, role1 7, Bob, role1, 7, Charles, role2 and Table2 bookingid, projectid 7, 1 and Table3 projectid, project, numberofrole1, numberofrole2 1, Test1, 2, 2 I would like the results to show that there are not the correct number of role2s for project Test1. To be honest, something like this is a bit beyond my ability, so I'm open to suggestions on the best way to do this. I'm using sqlite and php (it's only a small project). I suppose I could do something with the php at the end once I've got my results, but I wondered if there was a better way to do it with sqlite. I started by doing something like this: SELECT project, COUNT(numberofrole1) as "Role" FROM Table1 JOIN Table2 USING (projectid) JOIN Table3 USING (bookingid) WHERE role="role1" GROUP BY project But I can't work out how to compare the value returned as "Role" with the value got from numberofrole1 Any help is gratefully received.

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  • Zend Metadata Cache in file

    - by Matthieu
    I set up a metadata cache in Zend Framework because a lot of DESCRIBE queries were executed and it affected the performances. $frontendOptions = array ('automatic_serialization' => true); $backendOptions = array ('cache_dir' => CACHE_PATH . '/db-tables-metadata'); $cache = Zend_Cache::factory( 'Core', 'File', $frontendOptions, $backendOptions ); Zend_Db_Table::setDefaultMetadataCache($cache); I can indeed see the cache files created, and the website works great. However, when I launch unit tests, or a script of the same application that perform DB queries, I end up with an error because Zend couldn't read the cache files. This is because in the website, the cache files are created by the www user, and when I run phpunit or a script, it tries to read them with my user and it fails. Do you see any solution to that? I have some quickfix ideas but I'm looking for a good/stable solution. And I'd rather avoid running phpunit or the scripts as www if possible (for practical reasons).

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  • Hibernate OneToMany and ManyToOne confusion! Null List!

    - by squizz
    I have two tables... For example - Company and Employee (let's keep this real simple) Company( id, name ); Employee( id, company_id ); Employee.company_id is a foreign key. My entity model looks like this... Employee @ManyToOne(cascade = CascadeType.PERSIST) @JoinColumn(name = "company_id") Company company; Company @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER) @JoinColumn(name = "company_id") List<Employee> employeeList = new ArrayList<Employee>(); So, yeah I want a list of employees for a company. When I do the following... Employee e = new Employee(); e.setCompany(c); //c is an Company that is already in the database. DAO.insertEmployee(e); //this works fine! If I then get my Company object it's list is empty! Ive tried endless different ways from the Hibernate documentation! Obviously not tried the correct one yet! I just want the list to be populated for me or find out a sensible alternative. Help would be greatly appreciated, thanks!

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  • Ordering by number of rows?

    - by Rob
    Alright, so I have a table outputting data from a MySQL table in a while loop. Well one of the columns it outputs isn't stored statically in the table, instead it's the sum of how many times it appears in a different MySQL table. Sorry I'm not sure this is easy to understand. Here's my code: $query="SELECT * FROM list WHERE added='$addedby' ORDER BY time DESC"; $result=mysql_query($query); while($row=mysql_fetch_array($result, MYSQL_ASSOC)){ $loghwid = $row['hwid']; $sql="SELECT * FROM logs WHERE hwid='$loghwid' AND time < now() + interval 1 hour"; $query = mysql_query($sql) OR DIE(mysql_error()); $boots = mysql_num_rows($query); //Display the table } The above is the code displaying the table. As you can see it's grabbing data from two different MySQL tables. However I want to be able to ORDER BY $boots DESC. But as its a counting of a completely different table, I have no idea of how to go about doing that. I would appreciate any help, thank you.

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  • c# - sqllite dosnt save data i inserted

    - by samy
    I'm messing around with SQL lite and learning it. I got a table called People, I got some method that connect to the database and do some stuff, like show all the info. Now I'm trying to insert some data and here it get wierd for me. I have this method: private void ExecuteQuery(string txtQuery) { SetConnection(); sql_con.Open(); sql_cmd = sql_con.CreateCommand(); sql_cmd.CommandText = txtQuery; sql_cmd.ExecuteNonQuery(); sql_con.Close(); } and to see all the data I've got this method: private void LoadData() { SetConnection(); sql_con.Open(); sql_cmd = sql_con.CreateCommand(); string CommandText = "SELECT * FROM People"; DB = new SQLiteDataAdapter(CommandText, sql_con); DS.Reset(); DB.Fill(DS); DT = DS.Tables[0]; dataGridView1.DataSource = DT; sql_con.Close(); } When I inset some data and right afther it I call the LoadData(), I can see all the changes I made. After I close the program, and then open it agian and call LoadData(), I don't see the new info that I inserted before. I got some data that I used SQL lite GUI app to insert, and I can see that data every time I call the LoadData() method, but not mine. Do I need to do somthing else to make sure SQL lite saves all the data?

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  • Need help with simple NHibernate mapping...

    - by mplarsen
    Need help with a simple NHibernate relationship... Tables/Classes Request ------- RequestId Title … Keywords ------- RequestID (key) Keyword (key) Request mapping file <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="CR.Model" assembly="CR"> <class name="CR.Model.Request, CR table="[dbo].[Request]" lazy="true"> <id name="Id" column="[RequestID]"> <generator class="native" /> </id> <property name="RequestorID" column="[RequestorID]" /> <property name="RequestorOther" column="[RequestorOther]" /> … Keyword?? </class> </hibernate-mapping> How do I simply map multiple keywords to a request? I don't need another mapping file for the keyword class, do I? It's be great if I could not only get the associated keywords, but add them too...

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  • MySQL Multiple Table Join

    - by hitman001
    I have a 3 tables that I'm trying to join and get distinct results. CREATE TABLE `car` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(255) NOT NULL DEFAULT '', PRIMARY KEY (`id`) ) ENGINE=InnoDB mysql> select * from car; +----+-------+ | id | name | +----+-------+ | 1 | acura | +----+-------+ CREATE TABLE `tires` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `tire_desc` varchar(255) DEFAULT NULL, `car_id` int(10) unsigned NOT NULL, PRIMARY KEY (`id`), KEY `new_fk_constraint` (`car_id`), CONSTRAINT `new_fk_constraint` FOREIGN KEY (`car_id`) REFERENCES `car` (`id`) ON DELETE CASCADE ON UPDATE CASCADE ) ENGINE=InnoDB mysql> select * from tires; +----+-------------+--------+ | id | tire_desc | car_id | +----+-------------+--------+ | 1 | front_right | 1 | | 2 | front_left | 1 | +----+-------------+--------+ CREATE TABLE `lights` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `lights_desc` varchar(255) NOT NULL, `car_id` int(10) unsigned NOT NULL, PRIMARY KEY (`id`), KEY `new1_fk_constraint` (`car_id`), CONSTRAINT `new1_fk_constraint` FOREIGN KEY (`car_id`) REFERENCES `car` (`id`) ON DELETE CASCADE ON UPDATE CASCADE ) ENGINE=InnoDB mysql> select * from lights; +----+-------------+--------+ | id | lights_desc | car_id | +----+-------------+--------+ | 1 | right_light | 1 | | 2 | left_light | 1 | +----+-------------+--------+ Here is my query. mysql> SELECT name, group_concat(tire_desc), group_concat(lights_desc) FROM car left join tires on car.id = tires.car_id left join lights on car.id = car_id group by car.id; +-------+-----------------------------------------------+-----------------------------------------------+ | name | group_concat(tire_desc) | group_concat(lights_desc) | +-------+-----------------------------------------------+-----------------------------------------------+ | acura | front_right,front_right,front_left,front_left | right_light,left_light,right_light,left_light | +-------+-----------------------------------------------+-----------------------------------------------+ I get duplicate entires and this is what I would like to get. +-------+-----------------------------------------------+--------------------------------+ | name | group_concat(tire_desc) | group_concat(lights_desc) | +-------+-----------------------------------------------+--------------------------------+ | acura | front_right,front_left | right_light,left_light | +-------+-----------------------------------------------+--------------------------------+ I cannot use distinct in group_concat because I might have legitimate duplicates which I would like to keep. Is there any way to do this query using joins and not using inner selects like the statement below? SELECT name, (select group_concat(tire_desc) from tires where car.id = tires.car_id), (select group_concat(lights_desc) from lights where car.id = lights.car_id) FROM car Also, if I will use inner selects, will there be any performance issues over joins?

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  • Java: over-typed structures? To have many types in Object[]?

    - by HH
    Term over-type structure = a data structure that accepts different types, can be primitive or user-defined. I think ruby supports many types in structures such as tables. I tried a table with types 'String', 'char' and 'File' in Java but errs. How can I have over-typed structure in Java? How to show types in declaration? What about in initilization? Suppose a structure: INDEX VAR FILETYPE //0 -> file FILE //1 -> lineMap SizeSequence //2 -> type char //3 -> binary boolean //4 -> name String //5 -> path String Code import java.io.*; import java.util.*; public class Object { public static void print(char a) { System.out.println(a); } public static void print(String s) { System.out.println(s); } public static void main(String[] args) { Object[] d = new Object[6]; d[0] = new File("."); d[2] = 'T'; d[4] = "."; print(d[2]); print(d[4]); } } Errors Object.java:18: incompatible types found : java.io.File required: Object d[0] = new File("."); ^ Object.java:19: incompatible types found : char required: Object d[2] = 'T'; ^

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  • Css absolute position don't work in MS WORD

    - by Tim
    Hello! This is a sample: <html> <head> <title>word test</title> </head> <body> <div style='position: absolute; width: 30px; height: 50px; top: 100px; left: 20px; border-color: black; border-width: 1px; border-style: solid;'> <p>Hello!</p> </div> </body> </html> Save it as "word.doc" and open in MS WORD. Absolute position don't work! Div is rendered on the top of document and with 100% width. Why? I can't use a html tables. Version on ms word: 2003

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  • table column accepting "0" as a member Id

    - by user682417
    I have two tables one is members table with columns member id , member first name, member last name. I have another table guest passes with columns guest pass id and member id and issue date . I have a list view that will displays guest passes details (I.e) like member name and issue date and I have two text boxes those are for entering member name and issue date . member name text box is auto complete text box that working fine.... but the problem is when I am entering the name that is not in member table at this time it will accept and displays a blank field in list view in member name column and member id is stored as "0" in guest pass table ...... I don't want to display the member name empty blank and I don t want to store "0" in guest pass table and this is the insert statement sql2 = @"INSERT INTO guestpasses(member_Id,guestPass_IssueDate)"; sql2 += " VALUES("; sql2 += "'" + tbCGuestPassesMemberId.Text + "'"; sql2 += ",'" + tbIssueDate.Text + "'"; guestpassmemberId = memberid is there any validation that need to be done can any one suggestions on this pls... and this is the auto complete text box statement sql = @"SELECT member_Id FROM members WHERE concat(member_Firstname,'',member_Lastname) ='" + tbMemberName.Text+"'"; if (dt != null) { if (dt.Rows.Count > 0) { tbCGuestPassesMemberId.Text = Convert.ToInt32(dt.Rows[0] ["member_Id"]).ToString(); } } can any one help me on this ... is there any type of validation with sql query pls help me .....

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  • "Add another item" form functionality

    - by GSTAR
    I have a form that lets a user enter their career history - it's a very simple form with only 3 fields - type (dropdown), details (textfield) and year (dropdown). Basically I want to include some dynamic functionality whereby the user can enter multiple items on the same page and then submit them all in one go. I had a search on Google and found some examples but they were all based on tables - my markup is based on DIV tags: <div class="form-fields"> <div class="row"> <label for="type">Type</label> <select id="type" name="type"> <option value="Work">Work</option> </select> </div> <div class="row"> <label for="details">Details</label> <input id="details" type="text" name="details" /> </div> <div class="row"> <label for="year">Year</label> <select id="year" name="year"> <option value="2010">2010</option> </select> </div> </div> So basically the 3 DIV tags with class "row" need to be duplicated, or to simplify things - the div "form-fields" could just be duplicated. I am also aware that the input names would have to converted to array format. Additionally each item will require a "remove" button. There will be a main submit button at the bottom which submits all the data. Anyone got an elegant solution for this?

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  • Are programming languages and methods ineffective? (assembler and C knowledge needed)

    - by b-gen-jack-o-neill
    Hi, for a long time, I am thinking and studying output of C language compiler in asemlber form, as well as CPU architecture. I know this may be silly to you, but it seems to me that something is very ineffective. Please, don´t be angry if I am wrong, and there is some reason I do not see for all these principles. I will be very glad if you tell me why is it designed this way. I actually trully believe I am wrong, I know the genius minds of people which get PCs together knew a reason to do so. What exactly, do you ask? I´ll tell you right away, I use C as a example: 1, Stack local scope memory allocation: So, typical local memory allocation uses stack. Just copy esp to ebp and than allocate all the memory via ebp. OK, I would understand this if you explicitly need allocate RAM by default stack values, but if I do understand it correctly, modern OS use paging as a translation layer between application and physical RAM, when adress you desire is further translated before reaching actuall RAM byte. So why don´t just say 0x00000000 is int a,0x00000004 is int b and so? And access them just by mov 0x00000000,#10? Becouse you wont actually access memory blocks 0x00000000 and 0x00000004 but those your OS set the paging tables to. Actually, since memory allocation by ebp and esp use indirect adressing, "my" way would be even faster. 2, Variable allocation duplicitly: When you run aaplication, Loader load its code into RAM. When you create variable, or string, compiler generates code that pushes these values on the top o stack when created in main. So there is actuall instruction for do so, and that actuall number in memory. So, there are 2 entries of the same value in RAM. One in fomr of instruction, second in form of actuall bytes in the RAM. But why? Why not to just when declaring variable count at which memory block it would be, than when used, just insert this memory location?

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