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  • Swap unique indexed column values in database.

    - by Ramesh Soni
    I have a database table and one of the fields (not primary key) is having unique index on it. Now I want to swap values under this column for two rows. How could this be done? Two hack I know are: Delete both rows and re-insert them Update rows with some other value and swap and then update to actual value. But I don't want to go for these as they do not seem to be the appropriate solution to the problem. Could anyone help me out?

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  • Why wont this sort in Solr work?

    - by Camran
    I need to sort on a date-field type, which name is "mod_date". It works like this in the browser adress-bar: http://localhost:8983/solr/select/?&q=bmw&sort=mod_date+desc But I am using a phpSolr client which sends an URL to Solr, and the url sent is this: fq=+category%3A%22Bilar%22+%2B+car_action%3AS%C3%A4ljes&version=1.2&wt=json&json.nl=map&q=%2A%3A%2A&start=0&rows=5&sort=mod_date+desc // This wont work and is echoed after this in php: $queryString = http_build_query($params, null, $this->_queryStringDelimiter); $queryString = preg_replace('/%5B(?:[0-9]|[1-9][0-9]+)%5D=/', '=', $queryString); This wont work, I dont know why! Everything else works fine, all right fields are returned. But the sort doesn't work. Any ideas? Thanks BTW: The field "mod_date" contains something like: 2010-03-04T19:37:22.5Z EDIT: First I use PHP to send this to a SolrPhpClient which is another php-file called service.php: require_once('../SolrPhpClient/Apache/Solr/Service.php'); $solr = new Apache_Solr_Service('localhost', 8983, '/solr/'); $results = $solr->search($querystring, $p, $limit, $solr_params); $solr_params is an array which contains the solr-parameters (q, fq, etc). Now, in service.php: $params['version'] = self::SOLR_VERSION; // common parameters in this interface $params['wt'] = self::SOLR_WRITER; $params['json.nl'] = $this->_namedListTreatment; $params['q'] = $query; $params['sort'] = 'mod_date desc'; // HERE IS THE SORT I HAVE PROBLEM WITH $params['start'] = $offset; $params['rows'] = $limit; $queryString = http_build_query($params, null, $this->_queryStringDelimiter); $queryString = preg_replace('/%5B(?:[0-9]|[1-9][0-9]+)%5D=/', '=', $queryString); if ($method == self::METHOD_GET) { return $this->_sendRawGet($this->_searchUrl . $this->_queryDelimiter . $queryString); } else if ($method == self::METHOD_POST) { return $this->_sendRawPost($this->_searchUrl, $queryString, FALSE, 'application/x-www-form-urlencoded'); } The $results contain the results from Solr... So this is the way I need to get to work (via php). This code below (also on top of this Q) works but thats because I paste it into the adress bar manually, not via the PHPclient. But thats just for debugging, I need to get it to work via the PHPclient: http://localhost:8983/solr/select/?&q=bmw&sort=mod_date+des // Not via phpclient, but works UPDATE (2010-03-08): I have tried Donovans codes (the urls) and they work fine. Now, I have noticed that it is one of the parameters causing the 'SORT' not to work. This parameter is the "wt" parameter. If we take the url from top of this Q, (fq=+category%3A%22Bilar%22+%2B+car_action%3AS%C3%A4ljes&version=1.2&wt=json&json.nl=map&q=%2A%3A%2A&start=0&rows=5&sort=mod_date+desc), and just simply remove the "wt" parameter, then the sort works. BUT the results appear differently, thus making my php code not able to recognize the results I believe. Donovan would know this I think. I am guessing in order for the PHPClient to work, the results must be in a specific structure, which gets messed up as soon as I remove the wt parameter. Donovan, help me please... Here is some background what I use your SolrPhpClient for: I have a classifieds website, which uses MySql. But for the searching I am using Solr to search some indexed fields. Then Solr returns an array of ID:numbers (for all matches of the search criteria). Then I use those ID:numbers to find everything in a MySql db and fetch all other information (example is not searchable information). So simplified: Search - Solr returns all matches in an array of ID:nrs - Id:numbers from Solr are the same as the Id numbers in the MySql db, so I can just make a simple match agains every record with the ID matching the ID from the Solr results array. I don't use Faceting, no boosting, no relevancy or other fancy stuff. I only sort by the latest classified put, and give the option to users to also sort on the cheapest price. Nothing more. Then I use the "fq" parameter to do queries on different fields in Solr depending on category chosen by users (example "cars" in this case which in my language is "Bilar"). I am really stuck with this problem here... Thanks for all help

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  • How to optimise MySQL query containing a subquery?

    - by aidan
    I have two tables, House and Person. For any row in House, there can be 0, 1 or many corresponding rows in Person. But, of those people, a maximum of one will have a status of "ACTIVE", the others will all have a status of "CANCELLED". e.g. SELECT * FROM House LEFT JOIN Person ON House.ID = Person.HouseID House.ID | Person.ID | Person.Status 1 | 1 | CANCELLED 1 | 2 | CANCELLED 1 | 3 | ACTIVE 2 | 1 | ACTIVE 3 | NULL | NULL 4 | 4 | CANCELLED I want to filter out the cancelled rows, and get something like this: House.ID | Person.ID | Person.Status 1 | 3 | ACTIVE 2 | 1 | ACTIVE 3 | NULL | NULL 4 | NULL | NULL I've achieved this with the following sub select: SELECT * FROM House LEFT JOIN ( SELECT * FROM Person WHERE Person.Status != "CANCELLED" ) Person ON House.ID = Person.HouseID ...which works, but breaks all the indexes. Is there a better solution that doesn't? I'm using MySQL and all relevant columns are indexed. EXPLAIN lists nothing in possible_keys. Thanks.

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  • Entity Framework doesn't like 0..1 to * relationships.

    - by Orion Adrian
    I have a database framework where I have two tables. The first table has a single column that is an identity and primary key. The second table contains two columns. One is a nvarchar primary key and the other is a nullable foreign key to the first table. On the default import of the database I get the following error: Condition cannot be specified for Column member 'ForeignKeyId' because it is marked with a 'Computed' or 'Identity' StoreGeneratedPattern. where ForeignKeyId is the second foreign key reference in the second table. Is this just something the entity model doesn't do? Or am I missing something?

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  • How to have multiple tables with multiple joins

    - by williamsdb
    I have three tables that I need to join together and get a combination of results. I have tried using left/right joins but they don't give the desired results. For example: Table 1 - STAFF id name 1 John 2 Fred Table 2 - STAFFMOBILERIGHTS id staffid mobilerightsid rights --this table is empty-- Table 3 - MOBILERIGHTS id rightname 1 Login 2 View and what I need is this as the result... id name id staffid mobilerightsid rights id rightname 1 John null null null null 1 login 1 John null null null null 2 View 2 Fred null null null null 1 login 2 Fred null null null null 2 View I have tried the following : SELECT * FROM STAFFMOBILERIGHTS SMR RIGHT JOIN STAFF STA ON STA.STAFFID = SMR.STAFFID RIGHT JOIN MOBILERIGHTS MRI ON MRI.ID = SMR.MOBILERIGHTSID But this only returns two rows as follows: id name id staffid mobilerightsid rights id rightname null null null null null null 1 login null null null null null null 2 View Can what I am trying to achieve be done and if so how? Thanks

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  • LINQ for Java tool

    - by Milhous
    Would a LINQ for java be a useful tool? I have been working on a tool that will allow a Java object to map to a row in a database. Would this be useful for Java programmers? What features would be useful?

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  • Return order of MySQL SHOW COLUMNS

    - by rich
    Hey guys. Simple one this, but one I can't seem to find any information on so here goes. I need to find the columns in a specific table, which is no problem.... SHOW COLUMNS FROM tablename LIKE '%ColumnPrefix%'; But I need to know what order they will be returned, preferable by choosing to order the results ascending alphabetically. I have had no luck with using ORDER BY Field. Any ideas? Cheers!

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  • Subset sum problem

    - by MadBoy
    I'm having a problem with counting which is continuation of this question. I am not really a math person so it's really hard for me to figure out this subset sum problem which was suggested as resolution. I'm having 4 ArrayList in which I hold data: alId, alTransaction, alNumber, alPrice Type | Transaction | Number | Price 8 | Buy | 95.00000000 | 305.00000000 8 | Buy | 126.00000000 | 305.00000000 8 | Buy | 93.00000000 | 306.00000000 8 | Transfer out | 221.00000000 | 305.00000000 8 | Transfer in | 221.00000000 | 305.00000000 8 | Sell | 93.00000000 | 360.00000000 8 | Sell | 95.00000000 | 360.00000000 8 | Sell | 126.00000000 | 360.00000000 8 | Buy | 276.00000000 | 380.00000000 In the end I'm trying to get what's left for customer and what's left I put into 3 array lists: alNew (corresponds to alNumber), alNewPoIle (corresponds to alPrice), and alNewCo (corrseponds to alID) ArrayList alNew = new ArrayList(); ArrayList alNewPoIle = new ArrayList(); ArrayList alNewCo = new ArrayList(); for (int i = 0; i < alTransaction.Count; i++) { string tempAkcjeCzynnosc = (string) alTransaction[i]; string tempAkcjeInId = (string) alID[i]; decimal varAkcjeCena = (decimal) alPrice[i]; decimal varAkcjeIlosc = (decimal) alNumber[i]; int index; switch (tempAkcjeCzynnosc) { case "Transfer out": case "Sell": index = alNew.IndexOf(varAkcjeIlosc); if (index != -1) { alNew.RemoveAt(index); alNewPoIle.RemoveAt(index); alNewCo.RemoveAt(index); } else { ArrayList alTemp = new ArrayList(); decimal varAkcjeSuma = 0; for (int j = 0; j < alNew.Count; j ++) { string akcjeInId = (string) alNewCo[j]; decimal akcjeCena = (decimal) alNewPoIle[j]; decimal akcjeIlosc = (decimal) alNew[j]; if (tempAkcjeInId == akcjeInId && akcjeCena == varAkcjeCena) { alTemp.Add(j); varAkcjeSuma = varAkcjeSuma + akcjeIlosc; } } if (varAkcjeSuma == varAkcjeIlosc) { for (int j = alTemp.Count -1 ; j >=0 ; j --) { int tempIndex = (int) alTemp[j]; alNew.RemoveAt(tempIndex); alNewPoIle.RemoveAt(tempIndex); alNewCo.RemoveAt(tempIndex); } } } break; case "Transfer In": case "Buy": alNew.Add(varAkcjeIlosc); alNewPoIle.Add(varAkcjeCena); alNewCo.Add(tempAkcjeInId); break; } } Basically I'm adding and removing things from Array depending on Transaction Type, Transaction ID and Numbers. I'm adding numbers to ArrayList like 156, 340 (when it is TransferIn or Buy) etc and then i remove them doing it like 156, 340 (when it's TransferOut, Sell). My solution works for that without a problem. The problem I have is that for some old data employees were entering sum's like 1500 instead of 500+400+100+500. How would I change it so that when there's Sell/TransferOut or Buy/Transfer In and there's no match inside ArrayList it should try to add multiple items from thatArrayList and find elements that combine into aggregate. Inside my code I tried to resolve that problem with simple summing everything when there's no match (index == 1) if (index != -1) { alNew.RemoveAt(index); alNewPoIle.RemoveAt(index); alNewCo.RemoveAt(index); } else { ArrayList alTemp = new ArrayList(); decimal varAkcjeSuma = 0; for (int j = 0; j < alNew.Count; j ++) { string akcjeInId = (string) alNewCo[j]; decimal akcjeCena = (decimal) alNewPoIle[j]; decimal akcjeIlosc = (decimal) alNew[j]; if (tempAkcjeInId == akcjeInId && akcjeCena == varAkcjeCena) { alTemp.Add(j); varAkcjeSuma = varAkcjeSuma + akcjeIlosc; } } if (varAkcjeSuma == varAkcjeIlosc) { for (int j = alTemp.Count -1 ; j >=0 ; j --) { int tempIndex = (int) alTemp[j]; alNew.RemoveAt(tempIndex); alNewPoIle.RemoveAt(tempIndex); alNewCo.RemoveAt(tempIndex); } } But it only works if certain conditions are met, and fails for the rest.

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  • Get list of duplicate rows in MySql

    - by user347033
    Hi, i have a table like this ID nachname vorname 1 john doe 2 john doe 3 jim doe 4 Michael Knight I need a query that will return all the fields (select *) from the records that have the same nachname and vorname (in this case, records 1 and 2). Can anyone help me with this? Thanks

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  • query optimization

    - by Gaurav
    I have a query of the form SELECT uid1,uid2 FROM friend WHERE uid1 IN (SELECT uid2 FROM friend WHERE uid1='.$user_id.') and uid2 IN (SELECT uid2 FROM friend WHERE uid1='.$user_id.') The problem now is that the nested query SELECT uid2 FROM friend WHERE uid1='.$user_id.' returns a very large number of ids(approx. 5000). The table structure of the friend table is uid1(int), uid2(int). This table is used to determine whether two users are linked together as friends. Any workaround? Can I write the query in a different way? Or is there some other way to solve this issue. I'm sure I am not the first person to face such a problem. Any help would be greatly appreciated.

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  • Increase increment size to match GUID advantage

    - by TenaciousImpy
    Hi, I've been thinking of implementing this system, but can't help but feel there's a catch somewhere. One of the points of using GUID over incrementing int is that, in the future, if you were to merge databases together, you wouldn't have any clashes over the primary key/identifier. However, my approach is to set the increment size to X where X is the number of servers I'll most likely have in the future. Then, on each server, have the seed be an increment over the seed number on the previous server. That way, during merging, there would be no clashes with the primary key. Is this a safe, normal method or have I gone mental :)? Thanks

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  • Howto monitor traffic between IIS and MSSQL

    - by kockiren
    Hello @all, i try to check how much traffic flows between MSSQL Server and IIS Server in different Locations. There are 1 ipcop in every Location and i download the tcpdump file from one Firewall and search for DST=ipmssql and SRC=ipIIS but i did not find the ip from the Database Server. But there are traffic between both. Any suggestions why i did not find the IP Adress from the MSSQL Server? Is this an configuration failure in IPCop or is the Traffic between ISS and MSSQL so strange :-) Regards Rene

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  • Best Way to Generate Unique and consecutives numbers in Oracle

    - by RRUZ
    I need to generate unique and consecutive numbers (for use on an invoice), in a fast and reliable way. currently use a Oracle sequence, but in some cases generated numbers are not consecutive because of exceptions that may occur. I thought a couple of solutions to manage this problem, but neither of they convincing me. What solution do you recommend? Use a select max () SELECT MAX (NVL (doc_num, 0)) +1 FROM invoices Use a table to store the last number generated for the invoice. UPDATE docs_numbers SET last_invoice = last_invoice + 1 Another Solution?

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  • Jasper error: Caused by SQLServerException: Transaction (Process ID 58) was deadlocked on thread | c

    - by Saky
    I got the above error in my jasper report mail. The query that is used in the report is quite complicated (for me). Reading different posts I conclude that to solve this the I have to change the query to SET TRANSACTION ISOLATION LEVEL REPEATABLE READ GO BEGIN TRANSACTION ... my query ... COMMIT TRANSACTION ? I wonder if this is the correct way to solve the error and that if it has any side effects? Has it happened to anyone in the Jasper reports? Does anyone know if there is a better solution exist to the problem? (Although that I have not yet tested the above solution, if anyone can give any insight on this will be helpful.)

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  • Date format error in vb.net ?

    - by ahmed
    I get this error when I run the application Incorrect syntax near 12, on debugging I found that this error is caused due to the # along with the date. Dim backdate as datetime backdate = DateTime.Now.AddDays(-1) on binding the data to the grid to filter the backdate records this error is caused Incorrect syntax near 12. myqry = " select SRNO,SUBJECT,ID where datesend =" backdate Now i am trying to extract only the date or shall I divide the date into day , month and year with DATEPART and take into a variable or convert the date or what should i do , Please help ???

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  • date comparisons in Rails

    - by aressidi
    Hi there, I'm having trouble with a date comparison in a named scope. I'm trying to determine if an event is current based on its start and end date. Here's the named scope I'm using which kind of works, though not for events that have the same start and end date. named_scope :date_current, :conditions => ["Date(start_date) <= ? AND Date(end_date) >= ?", Time.now, Time.now] This returns the following record, though it should return two records, not one... >> Event.date_current => [#<Event id: 2161, start_date: "2010-02-15 00:00:00", end_date: "2010-02-21 00:00:00", ...] What it's not returning is this as well >> Event.find(:last) => #<Event id: 2671, start_date: "2010-02-16 00:00:00", end_date: "2010-02-16 00:00:00", ...> The server time seems to be in UTC and I presume that the entries are being stored in the DB in UTC. Any ideas as to what I'm doing wrong or what to try? Thanks!

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  • make multiple, composite query in oracle

    - by Meloun
    How can i make multiple, composite query in oracle? for example this several queries in one step? 1 CREATE TABLE test (id NUMBER PRIMARY KEY, name VARCHAR2(30)); 2 CREATE SEQUENCE test_sequence START WITH 1 INCREMENT BY 1; 3 CREATE OR REPLACE TRIGGER test_trigger BEFORE INSERT ON test REFERENCING NEW AS NEW FOR EACH ROW BEGIN SELECT test_sequence.nextval INTO :NEW.ID FROM dual; END; 4 INSERT INTO test (name) VALUES ('Jon'); 5 INSERT INTO test (name) VALUES ('Meloun');

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  • how to update tables' structures keeping current data

    - by Leon
    I have an c# application that uses tables from sqlserver 2008 database (runs on standalone pc with local sqlserver). Initially i install database on this pc with some initial data (there are some tables that application uses and the user doesn't touch). The question is - how can i upgrade this database after user created some new data without harming it (i continue developing and can add some new tables or stored procedures or add some columns to existing tables). Thanks in advance!

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  • What is the most efficient/elegant way to parse a flat table into a tree?

    - by Tomalak
    Assume you have a flat table that stores an ordered tree hierarchy: Id Name ParentId Order 1 'Node 1' 0 10 2 'Node 1.1' 1 10 3 'Node 2' 0 20 4 'Node 1.1.1' 2 10 5 'Node 2.1' 3 10 6 'Node 1.2' 1 20 What minimalistic approach would you use to output that to HTML (or text, for that matter) as a correctly ordered, correctly intended tree? Assume further you only have basic data structures (arrays and hashmaps), no fancy objects with parent/children references, no ORM, no framework, just your two hands. The table is represented as a result set, which can be accessed randomly. Pseudo code or plain English is okay, this is purely a conceptional question. Bonus question: Is there a fundamentally better way to store a tree structure like this in a RDBMS? EDITS AND ADDITIONS To answer one commenter's (Mark Bessey's) question: A root node is not necessary, because it is never going to be displayed anyway. ParentId = 0 is the convention to express "these are top level". The Order column defines how nodes with the same parent are going to be sorted. The "result set" I spoke of can be pictured as an array of hashmaps (to stay in that terminology). For my example was meant to be already there. Some answers go the extra mile and construct it first, but thats okay. The tree can be arbitrarily deep. Each node can have N children. I did not exactly have a "millions of entries" tree in mind, though. Don't mistake my choice of node naming ('Node 1.1.1') for something to rely on. The nodes could equally well be called 'Frank' or 'Bob', no naming structure is implied, this was merely to make it readable. I have posted my own solution so you guys can pull it to pieces.

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  • Need some serious help with self join issue.

    - by kralco626
    Well as you may know, you cannot index a view with a self join. Well actually even two joins of the same table, even if it's not technically a self join. A couple of guys from microsoft came up with a work around. But it's so complicated I don't understand it!!! The solution to the problem is here: http://jmkehayias.blogspot.com/2008/12/creating-indexed-view-with-self-join.html The view I want to apply this work around to is: create VIEW vw_lookup_test WITH SCHEMABINDING AS select count_big(*) as [count_all], awc_txt, city_nm, str_nm, stru_no, o.circt_cstdn_nm [owner], t.circt_cstdn_nm [tech], dvc.circt_nm, data_orgtn_yr from ((dbo.dvc join dbo.circt on dvc.circt_nm = circt.circt_nm) join dbo.circt_cstdn o on circt.circt_cstdn_user_id = o.circt_cstdn_user_id) join dbo.circt_cstdn t on dvc.circt_cstdn_user_id = t.circt_cstdn_user_id group by awc_txt, city_nm, str_nm, stru_no, o.circt_cstdn_nm, t.circt_cstdn_nm, dvc.circt_nm, data_orgtn_yr go Any help would be greatly apreciated!!! Thanks so much in advance!

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  • How do you compare dates in a LINQ query?

    - by Gina
    I am tring to compare a date from a asp calendar control to a date in the table.... here's what i have... it doesn't like the == ? var query = from details in db.TD_TravelCalendar_Details where details.StartDate == calStartDate.SelectedDate && details.EndDate == calEndDate.SelectedDate select details;

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