Search Results

Search found 36773 results on 1471 pages for 'sql statement syntax'.

Page 731/1471 | < Previous Page | 727 728 729 730 731 732 733 734 735 736 737 738  | Next Page >

  • [C#] How to create a constructor of a class that return a collection of instances of that class?

    - by codemonkie
    My program has the following class definition: public sealed class Subscriber { private subscription; public Subscriber(int id) { using (DataContext dc = new DataContext()) { this.subscription = dc._GetSubscription(id).SingleOrDefault(); } } } ,where _GetSubscription() is a sproc which returns a value of type ISingleResult<_GetSubscriptionResult> Say, I have a list of type List<int> full of 1000 ids and I want to create a collection of subscribers of type List<Subscriber>. How can I do that without calling the constructor in a loop for 1000 times? Since I am trying to avoid switching the DataContext on/off so frequently that may stress the database. TIA.

    Read the article

  • MySQL Query involving column names containing math operators

    - by devil_fingers
    I'm a MySQL scrub, and I have asked around and checked around the internet for what I'm sure will turn out to be something obvious, but I'm very frustrated with what I thought would be a very, very simple query not working. So here goes. Please be gentle. Basically, in a large database, some of the column names contain mathematical operators like "/" and "+." (Don't ask, it's not my database, I can't do anything about it). Here is the "essence" of my query (I took out the irrelevant stuff for the sake of this question): SELECT PlayerId, Season, WPA/LI AS WPALI FROM tht.stats_batting_master WHERE Season = "2010" AND teamid > 0 AND PA >= 502 GROUP BY playerid ORDER BY WPALI DESC When I run this, it returns "Unknown column 'LI' in 'field list'," I assume because it sees the "/" in WPA/LI as a division sign. Like I said, I'm sure this is easy enough to work around (it must be given how much this database is used), but I haven't' been able to figure out how. Thanks in advance for any help.

    Read the article

  • Exporting many tables on Oracle

    - by Adomas
    Hi, I would like to know, how to export many tables from oracle DB. I use exp.exe, create file expdat.dmp and so on. I choose to export only tables and there I must write which ones. Is there any chance of getting all of them? thanks

    Read the article

  • Why is this postgresql query so slow?

    - by user315975
    I'm no database expert, but I have enough knowledge to get myself into trouble, as is the case here. This query SELECT DISTINCT p.* FROM points p, areas a, contacts c WHERE ( p.latitude > 43.6511659465 AND p.latitude < 43.6711659465 AND p.longitude > -79.4677941889 AND p.longitude < -79.4477941889) AND p.resource_type = 'Contact' AND c.user_id = 6 is extremely slow. The points table has fewer than 2000 records, but it takes about 8 seconds to execute. There are indexes on the latitude and longitude columns. Removing the clause concering the resource_type and user_id make no difference. The latitude and longitude fields are both formatted as number(15,10) -- I need the precision for some calculations. There are many, many other queries in this project where points are compared, but no execution time problems. What's going on?

    Read the article

  • What is the reason not to use select * ?

    - by Chris Lively
    I've seen a number of people claim that you should specifically name each column you want in your select query. Assuming I'm going to use all of the columns anyway, why would I not use SELECT *? Even considering the question from 9/24, I don't think this is an exact duplicate as I'm approaching the issue from a slightly different perspective. One of our principles is to not optimize before it's time. With that in mind, it seems like using SELECT * should be the preferred method until it is proven to be a resource issue or the schema is pretty much set in stone. Which, as we know, won't occur until development is completely done. That said, is there an overriding issue to not use SELECT *?

    Read the article

  • How would I associate a "Note" class to 4+ classes without creating lookup table for each associatio

    - by Gthompson83
    Im creating a project tasklist application. I have project, section, task, issue classes, and would like to use one class to be able to add simple notes to any object instance of those classes. The task, issue tables both use a standard identity field as a primary key. The section table has a two field primary key. The project table has a single int primary key defined by the user. Is there a way to associate the note class with each of these without using a seperate lookup table for each class? I'm not so sure my original idea is a decent way to implement this. I considered the following (each variable mapping to a field n the notes table. Private _NoteId As Integer Private _ProjectId As Integer Private _SectionId As Integer Private _SectionId2 As Integer Private _TaskId As Integer Private _IssueId As Integer Private _Note As String Private _UserId As Guid Then I would be able to write seperate methods (getProjectNotes, getTaskNotes) to get notes attached to each class. I started writing this a few weeks ago but got pulled away before i could finish. When revisiting this code today my first thought "this is retarded". Thoughts on drawbacks to this design?

    Read the article

  • Why is Postgres doing a Hash in this query?

    - by Claudiu
    I have two tables: A and P. I want to get information out of all rows in A whose id is in a temporary table I created, tmp_ids. However, there is additional information about A in the P table, foo, and I want to get this info as well. I have the following query: SELECT A.H_id AS hid, A.id AS aid, P.foo, A.pos, A.size FROM tmp_ids, P, A WHERE tmp_ids.id = A.H_id AND P.id = A.P_id I noticed it going slowly, and when I asked Postgres to explain, I noticed that it combines tmp_ids with an index on A I created for H_id with a nested loop. However, it hashes all of P before doing a Hash join with the result of the first merge. P is quite large and I think this is what's taking all the time. Why would it create a hash there? P.id is P's primary key, and A.P_id has an index of its own.

    Read the article

  • Basic Hibernate question using and sql query

    - by Aerosteak
    Hello Sorry if this is basic but I cannot find the solution anywhere. I have an java Object ‘Person’ with 3 properties firstname,lastname and username. I have an Oracle Store procedure returning a Resultset with the 3 column. All works fine for that. Now I have another StoreProcedure that will only return firstname and lastname but not username. I get the following error : « could not read column value from result set username. » Hibernate tries to fetch the username property from the resultset. If I remove the property username, then it works. Do I have to Create a Special Pojo for Each type of resultset or can I tell Hibernate what to map for each result set? Please help.

    Read the article

  • Oracle sql developer can acess from loalhost but not ip address

    - by Welcome Always
    Here i have installed widows server 2008 64 orale 11g r2 64 now i want to access this from the ip address that i have set to my server not working i can't access trough the ip address.... when i use on my application .....local host it can get connected but when i add the ip for example 10.0.0.2 it's not connecting now simply also on local when i write the ip address it's not connecting but with localhost works fine..... so even i have used listener. regards

    Read the article

  • SELECT set of most recent id, amount FROM table, where id occurs many times

    - by Jon Cram
    I have a table recording the amount of data transferred by a given service on a given date. One record is entered daily for a given service. I'd like to be able to retrieve the most recent amount for a set of services. Example data set: serviceId | amount | date ------------------------------- 1 | 8 | 2010-04-12 2 | 11 | 2010-04-12 2 | 14 | 2010-04-11 3 | 9 | 2010-04-11 1 | 6 | 2010-04-10 2 | 5 | 2010-04-10 3 | 22 | 2010-04-10 4 | 17 | 2010-04-19 Desired response (service ids 1,2,3): serviceId | amount | date ------------------------------- 1 | 8 | 2010-04-12 2 | 11 | 2010-04-12 3 | 9 | 2010-04-11 Desired response (service ids 2, 4): serviceId | amount | date ------------------------------- 2 | 11 | 2010-04-12 4 | 17 | 2010-04-19 This retrieves the equivalent as running the following once per serviceId: SELECT serviceId, amount, date FROM table WHERE serviceId = <given serviceId> ORDER BY date DESC LIMIT 0,1 I understand how I can retrieve the data I want in X queries. I'm interested to see how I can retrieve the same data using either a single query or at the very least less than X queries. I'm very interested to see what might be the most efficient approach. The table currently contains 28809 records. I appreciate that there are other questions that cover selecting the most recent set of records. I have examined three such questions but have been unable to apply the solutions to my problem.

    Read the article

  • Violation of primary key constraint, multiple users

    - by MC.
    Lets say UserA and UserB both have an application open and are working with the same type of data. UserA inserts a record into the table with value 10 (PrimaryKey='A'), UserB does not currently see the value UserA entered and attempts to insert a new value of 20 (PrimaryKey='A'). What I wanted in this situation was a DBConcurrencyException, but instead what I have is a primary key violation. I understand why, but I have no idea how to resolve this. What is a good practice to deal with such a circumstance? I do not want to merge before updating the database because I want an error to inform the user that multiple users updated this data.

    Read the article

  • LINQ Left Join And Right Join

    - by raja
    Hi, I need a help, I have two dataTable called A and B , i need all rows from A and matching row of B Ex: A: B: User | age| Data ID | age|Growth 1 |2 |43.5 1 |2 |46.5 2 |3 |44.5 1 |5 |49.5 3 |4 |45.6 1 |6 |48.5 I need Out Put: User | age| Data |Growth ------------------------ 1 |2 |43.5 |46.5 2 |3 |44.5 | 3 |4 |45.6 |

    Read the article

  • Access is re-writing - and breaking - my query!

    - by FrustratedWithFormsDesigner
    I have a query in MS Access (2003) that makes use of a subquery. The subquery part looks like this: ...FROM (SELECT id, dt, details FROM all_recs WHERE def_cd="ABC-00123") AS q1,... And when I switch to Table View to verify the results, all is OK. Then, I wanted the result of this query to be printed on the page header for a report (the query returns a single row that is page-header stuff). I get an error because the query is suddenly re-written as: ...FROM [SELECT id, dt, details FROM all_recs WHERE def_cd="ABC-00123"; ] AS q1,... So it's Ok that the round brackets are automatically replaced by square brackets, Access feels it needs to do that, fine! But why is it adding the ; into the subquery, which causes it to fail? I suppose I could just create new query objects for these subqueries, but it seems a little silly that I should have to do that.

    Read the article

  • SQL query INSERT not working inserting values into my DB.

    - by Aiden Ryan
    Hello, I'm trying to insert registration data into a database but my php code isn't inserting the values into the DB although I'm not getting any errors either, can someone help me? this is the code i'm currently using: $connect = mysql_connect("localhost","myusername","mypassword"); mysql_select_db("application"); $queryreg = mysql_query('INSERT INTO users("username","password","email","date") VALUES("$username","$password","$email","$date")'); die ("You Have Been Registered."); I just need to add the username password email and date into the fields i have specified but it won't work, please someone help!

    Read the article

  • JQuery Onclick display selected info

    - by Emily
    I want to display the selected price, category and size on the dropdown slideingDiv. But what I have done below is not working. I have try to echo out to see if the data have been sent thought but I got nothing. Is anything wrong with my code? Script <script type="text/javascript"> $(document).ready(function () { $(".slidingDiv").hide(); $(".show_hide").show(); $('.show_hide').click(function () { $(".slidingDiv").slideToggle(); }); }); </script> Button <button a href="product.php?ProdID=<?php echo $id; ?>" class="show_hide" id="button" name="button">Add to cart</a></button> PHP <div class="slidingDiv"> <?php dbconnect(); $pid = $_POST['pid']; $length = $_POST["size"]; $qty = $_POST['Qty']; $Category = $_POST['Category']; $stmt4 = $conn->prepare(" SELECT Product.Name as ProductName, Category.Name, size, Price FROM item_Product, Product, Category WHERE Product.ProdID =:pid AND size= :length AND Category.Name = :Category Limit 1"); $stmt4->bindParam('pid',$pid); $stmt4->bindParam('length',$length); $stmt4->bindParam('Category',$Category); $stmt4->execute(); foreach ($stmt4->fetchAll(PDO::FETCH_ASSOC) as $row4 ) { $product_name = $row4["ProductName"]; $price = $row4["Price"]; $length = $row4["size"]; $Category = $row4["Name"]; ?> Item was added shopping bag </br> Name:<?php echo $row4['ProductName']; ?> </br> Length:<?php echo $row4['size']; ?> </br> Category:<?php echo $row4['Name']; ?> </br> Price:<?php echo $row4['Price']; ?> </br> <?php } ?> <a href="cart.php">View Cart</a> </div>

    Read the article

  • mySQL: Order by field size/length

    - by Sadi
    Here is a table structure (e.g. test): __________________________________________ | Field Name | Data Type | |________________|_________________________| | id | BIGINT (20) | |________________|_________________________| | title | varchar(25) | |________________|_________________________| | description | text | |________________|_________________________| A query like: SELECT * FROM TEST ORDER BY description; But I would like to order by the field size/length of the field description. The field type will be TEXT or BLOB.

    Read the article

  • Can I concatenate multiple MySQL rows into one field?

    - by Dean
    Using MySQL, I can do something like select hobbies from peoples_hobbies where person_id = 5; and get: shopping fishing coding but instead I just want 1 row, 1 col: shopping, fishing, coding The reason is that I'm selecting multiple values from multiple tables, and after all the joins I've got a lot more rows than I'd like. I've looked for a function on MySQL Doc and it doesn't look like the CONCAT or CONCAT_WS functions accept result sets, so does anyone here know how to do this?

    Read the article

  • Group and count in Rails

    - by alamodey
    I have this bit of code and I get an empty object. @results = PollRoles.find( :all, :select => 'option_id, count(*) count', :group => 'option_id', :conditions => ["poll_id = ?", @poll.id]) Is this the correct way of writing the query? I want a collection of records that have an option id and the number of times that option id is found in the PollRoles model. EDIT: This is how I''m iterating through the results: <% @results.each do |result| %> <% @option = Option.find_by_id(result.option_id) %> <%= @option.question %> <%= result.count %> <% end %>

    Read the article

  • How to add user customized data to database?

    - by CSharperWithJava
    I am trying to design a sqlite database that will store notes. Each of these notes will have common fields like title, due date, details, priority, and completed. In addition though, I would like to add data for more specialized notes like price for shopping list items and author/publisher data for books. I also want to have a few general purpose fields that users can fill with whatever text data they want. How can I design my database table in this case? I could just have a field for each piece of data for every note, but that would waste a lot of fields and I'd like to have other options and suggestions.

    Read the article

  • What are the Limitations for Connecting to an Access Query in Excel

    - by thornomad
    I have an Access 2007 database that has a number of tables, some are fairly large (100,000+ records); I have created a union query to pull some of the same types of data from multiple tables into one large query for pivot table manipulation and reporting. For example: SELECT Language FROM Table1 UNION ALL SELECT Language FROM Table2 UNION ALL SELECT Language FROM Table3; This works. I found, quickly, however, that a union query will not show up when connecting to the datasource from Excel 2007. So, I created a second query to reference the union query. Like so: SELECT * FROM [The Above Union Query]; This query works and it, initially, was accessible from Excel. Time passed, I've added more data. Suddenly, when I connect to my Access database from Excel my query referencing the union has disappeared. MS Access shows no signs of an issue (data displays in Access) and my other non-union queries are showing up in Excel 2007 ... but not the one that references the union. What could be going on? Why did it disappear? I noticed if I switch some of the referenced tables in the union query to a smaller table (with less rows) all of sudden the query appears in Excel again. At least, I think that's what the difference is. I really can't put my finger on why some of the union queries won't show up and some will. Am stumped and need some guidance. Thanks.

    Read the article

  • Showing multiple models in a single ListView

    - by Veer
    I've three models (Contacts, Notes, Reminders). I want to search all these and produce the filtered result in a single listview and depending upon the selection I've to display the corresponding view(UserControl) to its right. I want the right way of implementing the design or atleast alternatives to this method that I've tried. Now I've tried it using a IntegratedViewModel having all the properties from all the three models. public class IntegratedViewModel { ContactModel _contactModel; NoteModel _noteModel; public IntegratedViewModel(ContactModel contactModel) { _contactModel = contactModel; } // similarly for other models also public string DisplayTitle // For displaying in ListView { get; //same as set set { If(_contactModel != null) return _contactModel.Name; If(_noteModel != null) return _noteModel.Title; } } // All other properties from the three models includin the Name/Title properties for displaying them in the corresponding views(UserControl) } Now I set the itemsSource as the List<IntegratedViewModel>. I've to now bind the visibility of the views to some properties in the MainViewModel. I tried setting bool properties like IsContactViewSelected, IsNoteViewSelected using the setter of SelectedEntity property which is bound to the ListView's SelectedItem. public SelectedEntity { //get set { oldvalue = _selectedEntity; _selectedEntity = value; // now i find the Type of model selected using oldvalue.ModelType // where ModelType is a property in the IntegratedViewModel // according to the type, i set one of the above bool properties to false // and do the same for _selectedEntity but set the property to true // so that the view corresponding to the selectedEntityType is visible // and others are collapsed } } Here is the problem: For eg: let us say, I selected an item of type ContactModel, the old selection being NoteModel. I set the property IsNoteModelSelected to false according to the oldvalue, it sets the property and then Raises the propertychanged event and does not go and check the remaining if condition where i check for _selectedEntity which is used to set the IsContactModelSelected to true.

    Read the article

  • How to verify if two tables have exactly the same data?

    - by SiLent SoNG
    Basically we have one table (original table) and it is backed up into another table (backup table); thus the two tables have exactly the same schema. At the beginning both tables (original table and backup table) contains exactly the same set of data. After sometime for some reason I need to verify whether dataset in the original table has changed or not. In order to do this I have to compare the dataset in the original table against the backup table. Let's say the original table has the following schema: `create table LemmasMapping ( lemma1 int, lemma2 int, index ix_lemma1 using btree (lemma1), index ix_lemma2 using btree (lemma2) )` How could I achieve the dataset comparision? Update: the table does not have a primary key. It simply stores mappings between two ids.

    Read the article

< Previous Page | 727 728 729 730 731 732 733 734 735 736 737 738  | Next Page >