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  • Populating a foreign key table with variable user input

    - by Vincent
    I'm working on a website that will be based on user contributed data, submitted using a regular HTML form. To simplify my question, let's say that there will be two fields in the form: "User Name" and "Country" (this is just an example, not the actual site). There will be two tables in the database : "countries" and "users," with "users.country_id" being a foreign key to the "countries" table (one-to-many). The initial database will be empty. Users from all over the world will submit their names and the countries they live in and eventually the "countries" table will get filled out with all of the country names in the world. Since one country can have several alternative names, input like Chile, Chili, Chilli will generate 3 different records in the countries table, but in fact there is only one country. When I search for records from Chile, Chili and Chilli will not be included. So my question is - what would be the best way to deal with a situation like this, with conditions such that the initial database is empty, no other resources are available and everything is based on user input? How can I organize it in such way that Chile, Chili and Chilli would be treated as one country, with minimum manual interference. What are the best practices when it comes to normalizing user submitted data and is there a scientific term for this? I'm sure this is a common problem. Again, I used country names just to simplify my question, it can be anything that has possible different spellings.

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  • Getting table schema from a query

    - by Appu
    As per MSDN, SqlDataReader.GetSchemaTable returns column metadata for the query executed. I am wondering is there a similar method that will give table metadata for the given query? I mean what tables are involved and what aliases it has got. In my application, I get the query and I need to append the where clause programically. Using GetSchemaTable(), I can get the column metadata and the table it belongs to. But even though table has aliases, it still return the real table name. Is there a way to get the aliase name for that table? Following code shows getting the column metadata. const string connectionString = "your_connection_string"; string sql = "select c.id as s,c.firstname from contact as c"; using(SqlConnection connection = new SqlConnection(connectionString)) using(SqlCommand command = new SqlCommand(sql, connection)) { connection.Open(); SqlDataReader reader = command.ExecuteReader(CommandBehavior.KeyInfo); DataTable schema = reader.GetSchemaTable(); foreach (DataRow row in schema.Rows) { foreach (DataColumn column in schema.Columns) { Console.WriteLine(column.ColumnName + " = " + row[column]); } Console.WriteLine("----------------------------------------"); } Console.Read(); } This will give me details of columns correctly. But when I see BaseTableName for column Id, it is giving contact rather than the alias name c. Is there any way to get the table schema and aliases from a query like the above? Any help would be great!

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  • Setting up relations/mappings for a SQLAlchemy many-to-many database

    - by Brent Ramerth
    I'm new to SQLAlchemy and relational databases, and I'm trying to set up a model for an annotated lexicon. I want to support an arbitrary number of key-value annotations for the words which can be added or removed at runtime. Since there will be a lot of repetition in the names of the keys, I don't want to use this solution directly, although the code is similar. My design has word objects and property objects. The words and properties are stored in separate tables with a property_values table that links the two. Here's the code: from sqlalchemy import Column, Integer, String, Table, create_engine from sqlalchemy import MetaData, ForeignKey from sqlalchemy.orm import relation, mapper, sessionmaker from sqlalchemy.ext.declarative import declarative_base engine = create_engine('sqlite:///test.db', echo=True) meta = MetaData(bind=engine) property_values = Table('property_values', meta, Column('word_id', Integer, ForeignKey('words.id')), Column('property_id', Integer, ForeignKey('properties.id')), Column('value', String(20)) ) words = Table('words', meta, Column('id', Integer, primary_key=True), Column('name', String(20)), Column('freq', Integer) ) properties = Table('properties', meta, Column('id', Integer, primary_key=True), Column('name', String(20), nullable=False, unique=True) ) meta.create_all() class Word(object): def __init__(self, name, freq=1): self.name = name self.freq = freq class Property(object): def __init__(self, name): self.name = name mapper(Property, properties) Now I'd like to be able to do the following: Session = sessionmaker(bind=engine) s = Session() word = Word('foo', 42) word['bar'] = 'yes' # or word.bar = 'yes' ? s.add(word) s.commit() Ideally this should add 1|foo|42 to the words table, add 1|bar to the properties table, and add 1|1|yes to the property_values table. However, I don't have the right mappings and relations in place to make this happen. I get the sense from reading the documentation at http://www.sqlalchemy.org/docs/05/mappers.html#association-pattern that I want to use an association proxy or something of that sort here, but the syntax is unclear to me. I experimented with this: mapper(Word, words, properties={ 'properties': relation(Property, secondary=property_values) }) but this mapper only fills in the foreign key values, and I need to fill in the other value as well. Any assistance would be greatly appreciated.

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  • Nhibernate: Stop it from joining to a table that is not needed

    - by Aaron
    I have two tables (tbArea, tbPost) that relate to the following classes. class Area { int ID string Name ... } class Post { int ID string Title Area Area ... } These two classes map up with Fluent Nhibernate. Below is the post mapping. public class PostMapping : ClassMap<Post> { public PostMapping() { Cache.NonStrictReadWrite(); this.Table("tbPost"); Id(x => x.ID) .Column("PostID") .GeneratedBy .Identity(); References(x => x.Area) .ForeignKey("AreaID") .Column("AreaID"); ... } } Any time I perform a query on the Post table "where AreaID = 1(any AreaId)", nhibernate will join to the area table. (What Nhibernate generates for a query) SELECT post fields , area fields (automatically added) FROM tbPost p LEFT JOIN tbArea a on p.areaid = a.areaid where p.areaid = 1 I have tried setting Area to LazyLoad, to Fetch.Select, ReadOnly, and any other setting on the reference and still it will always join to Area. I am trying to optimize the backend database queries, and since I don't need the area object loaded just filtered I would like to eliminate the unnecessary join to Area each time I Query post. What configurations do I need to change or mappings to get area to still be related to post in my objects, but not query it when I filter on AreaID?

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  • best practice - loging events (general) and changes (database)

    - by b0x0rz
    need help with logging all activities on a site as well as database changes. requirements: * should be in database * should be easily searchable by initiator (user name / session id), event (activity type) and event parameters i can think of a database design but either it involves a lot of tables (one per event) so i can log each of the parameters of an event in a separate field OR it involves one table with generic fields (7 int numeric and 7 text types) and log everything in one table with event type field determining what parameter got written where (and hoping that i don't need more than 7 fields of a certain type, or 8 or 9 or whatever number i choose)... example of entries (the usual things): [username] login failed @datetime [username] login successful @datetime [username] changed password @datetime, estimated security of password [low/ok/high/perfect] @datetime [username] clicked result [result number] [result id] after searching for [search string] and got [number of results] @datetime [username] clicked result [result number] [result id] after searching for [search string] and got [number of results] @datetime [username] changed profile name from [old name] to [new name] @datetime [username] verified name with [credit card type] credit card @datetime datbase table [table name] purged of old entries @datetime etc... so anyone dealt with this before? any best practices / links you can share? i've seen it done with the generic solution mentioned above, but somehow that goes against what i learned from database design, but as you can see the sheer number of events that need to be trackable (each user will be able to see this info) is giving me headaches, BUT i do LOVE the one event per table solution more than the generic one. any thoughts? edit: also, is there maybe an authoritative list of such (likely) events somewhere? thnx stack overflow says: the question you're asking appears subjective and is likely to be closed. my answer: probably is subjective, but it is directly related to my issue i have with designing a database / writing my code, so i'd welcome any help. also i tried narrowing down the ideas to 2 so hopefully one of these will prevail, unless there already is an established solution for these kinds of things.

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  • UITableView with Custom Cell only loads one row of data at a time

    - by Anton
    For my table, I've created a custom cell that has two labels. I also have two arrays with data, that I use to respectively assign each label in the cell. My problem, is that when the table is viewed, only the first row has data, and the rest of the data "sorta" loads when I start scrolling down. By "sorta", only the first row will load at a time. The only time I get to see all the data, is when I scroll to the bottom, then scroll up again. I've used the cellForRowAtIndexPath method to load the data into my cell. - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CustomCellIdentifier = @"CustomCellIdentifier"; CustomCell *cell = (CustomCell *)[tableView dequeueReusableCellWithIdentifier:CustomCellIdentifier]; if (cell == nil) { NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"CustomCell" owner:self options:nil]; for (id oneObject in nib) if ([oneObject isKindOfClass:[CustomCell class]]) cell = (CustomCell *)oneObject; } NSUInteger row = [indexPath row]; //I have two tables to fill up, hence the tag if statement if ([tableView tag] == 0) { cell.arriveTimeLabel.text = [homeBoundTimes objectAtIndex:row]; cell.departTimeLabel.text = [homeBoundTimes objectAtIndex:row]; } else if ([tableView tag] == 1) { cell.arriveTimeLabel.text = [workBoundTimes objectAtIndex:row]; cell.departTimeLabel.text = [workBoundTimes objectAtIndex:row]; } return cell; } Is it possible that its only getting called when the top cell is being called?

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  • Reading/Writing DataTables to and from an OleDb Database LINQ

    - by jsmith
    My current project is to take information from an OleDbDatabase and .CSV files and place it all into a larger OleDbDatabase. I have currently read in all the information I need from both .CSV files, and the OleDbDatabase into DataTables.... Where it is getting hairy is writing all of the information back to another OleDbDatabase. Right now my current method is to do something like this: OleDbTransaction myTransaction = null; try { OleDbConnection conn = new OleDbConnection("PROVIDER=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + Database); conn.Open(); OleDbCommand command = conn.CreateCommand(); string strSQL; command.Transaction = myTransaction; strSQL = "Insert into TABLE " + "(FirstName, LastName) values ('" + FirstName + "', '" + LastName + "')"; command.CommandType = CommandType.Text; command.CommandText = strSQL; command.ExecuteNonQuery(); conn.close(); catch (Exception) { // IF invalid data is entered, rolls back the database myTransaction.Rollback(); } Of course, this is very basic and I'm using an SQL command to commit my transactions to a connection. My problem is I could do this, but I have about 200 fields that need inserted over several tables. I'm willing to do the leg work if that's the only way to go. But I feel like there is an easier method. Is there anything in LINQ that could help me out with this?

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  • Moving information between databases

    - by williamjones
    I'm on Postgres, and have two databases on the same machine, and I'd like to move some data from database Source to database Dest. Database Source: Table User has a primary key Table Comments has a primary key Table UserComments is a join table with two foreign keys for User and Comments Dest looks just like Source in structure, but already has information in User and Comments tables that needs to be retained. I'm thinking I'll probably have to do this in a few steps. Step 1, I would dump Source using the Postgres Copy command. Step 2, In Dest I would add a temporary second_key column to both User and Comments, and a new SecondUserComments join table. Step 3, I would import the dumped file into Dest using Copy again, with the keys input into the second_key columns. Step 4, I would add rows to UserComments in Dest based on the contents of SecondUserComments, only using the real primary keys this time. Could this be done with a SQL command or would I need a script? Step 5, delete the SecondUserComments table and remove the second_key columns. Does this sound like the best way to do this, or is there a better way I'm overlooking?

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  • How to Store and Retrieve Images Using MsSQL (Server Management Studio)

    - by Joe Majewski
    I am having difficulties when trying to insert files into an MsSQL database. I'll try to break this down as best as I can: What data type should I be using to store image files (jpeg/png/gif/etc)? Right now my table is using the image data type, but I am curious if varbinary would be a better option. How would I go about inserting the image into the database? Does Microsoft SQL Server Management Studio have any built in functions that allow insertions of files into tables? If so, how is that done? Also, how could this be done through the use of an HTML form with PHP handling the input data and placing it into the table? How would I fetch the image from the table and display it on the page? I understand how to SELECT the cell's contents, but how would I go about translating that into a picture. Would I have to have a header(Content type: image/jpeg)? I have no problem doing any of these things with MySQL, but the MsSQL environment is still new to me, and I am working on a project for my job that requires the use of stored procedures to grab various data. Any and all help is appreciated. Thank you very much for your responses!

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  • SQL Query Math Gymnastics

    - by keruilin
    I have two tables of concern here: users and race_weeks. User has many race_weeks, and race_week belongs to User. Therefore, user_id is a fk in the race_weeks table. I need to perform some challenging math on fields in the race_weeks table in order to return users with the most all-time points. Here are the fields that we need to manipulate in the race_weeks table. races_won (int) races_lost (int) races_tied (int) points_won (int, pos or neg) recordable_type(varchar, Robots can race, but we're only concerned about type 'User') Just so that you fully understand the business logic at work here, over the course of a week a user can participate in many races. The race_week record represents the summary results of the user's races for that week. A user is considered active for the week if races_won, races_lost, or races_tied is greater than 0. Otherwise the user is inactive. So here's what we need to do in our query in order to return users with the most points won (actually net_points_won): Calculate each user's net_points_won (not a field in the DB). To calculate net_points, you take (1000 * count_of_active_weeks) - sum(points__won). (Why 1000? Just imagine that every week the user is spotted a 1000 points to compete and enter races. We want to factor-out what we spot the user because the user could enter only one race for the week for 100 points, and be sitting on 900, which we would skew who actually EARNED the most points.) This one is a little convoluted, so let me know if I can clarify further.

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  • Creating a [materialised]view from generic data in Oracle/Mysql

    - by Andrew White
    I have a generic datamodel with 3 tables CREATE TABLE Properties ( propertyId int(11) NOT NULL AUTO_INCREMENT, name varchar(80) NOT NULL ) CREATE TABLE Customers ( customerId int(11) NOT NULL AUTO_INCREMENT, customerName varchar(80) NOT NULL ) CREATE TABLE PropertyValues ( propertyId int(11) NOT NULL, customerId int(11) NOT NULL, value varchar(80) NOT NULL ) INSERT INTO Properties VALUES (1, 'Age'); INSERT INTO Properties VALUES (2, 'Weight'); INSERT INTO Customers VALUES (1, 'Bob'); INSERT INTO Customers VALUES (2, 'Tom'); INSERT INTO PropertyValues VALUES (1, 1, '34'); INSERT INTO PropertyValues VALUES (2, 1, '80KG'); INSERT INTO PropertyValues VALUES (1, 2, '24'); INSERT INTO PropertyValues VALUES (2, 2, '53KG'); What I would like to do is create a view that has as columns all the ROWS in Properties and has as rows the entries in Customers. The column values are populated from PropertyValues. e.g. customerId Age Weight 1 34 80KG 2 24 53KG I'm thinking I need a stored procedure to do this and perhaps a materialised view (the entries in the table "Properties" change rarely). Any tips?

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  • What's the most efficient query?

    - by Aaron Carlino
    I have a table named Projects that has the following relationships: has many Contributions has many Payments In my result set, I need the following aggregate values: Number of unique contributors (DonorID on the Contribution table) Total contributed (SUM of Amount on Contribution table) Total paid (SUM of PaymentAmount on Payment table) Because there are so many aggregate functions and multiple joins, it gets messy do use standard aggregate functions the the GROUP BY clause. I also need the ability to sort and filter these fields. So I've come up with two options: Using subqueries: SELECT Project.ID AS PROJECT_ID, (SELECT SUM(PaymentAmount) FROM Payment WHERE ProjectID = PROJECT_ID) AS TotalPaidBack, (SELECT COUNT(DISTINCT DonorID) FROM Contribution WHERE RecipientID = PROJECT_ID) AS ContributorCount, (SELECT SUM(Amount) FROM Contribution WHERE RecipientID = PROJECT_ID) AS TotalReceived FROM Project; Using a temporary table: DROP TABLE IF EXISTS Project_Temp; CREATE TEMPORARY TABLE Project_Temp (project_id INT NOT NULL, total_payments INT, total_donors INT, total_received INT, PRIMARY KEY(project_id)) ENGINE=MEMORY; INSERT INTO Project_Temp (project_id,total_payments) SELECT `Project`.ID, IFNULL(SUM(PaymentAmount),0) FROM `Project` LEFT JOIN `Payment` ON ProjectID = `Project`.ID GROUP BY 1; INSERT INTO Project_Temp (project_id,total_donors,total_received) SELECT `Project`.ID, IFNULL(COUNT(DISTINCT DonorID),0), IFNULL(SUM(Amount),0) FROM `Project` LEFT JOIN `Contribution` ON RecipientID = `Project`.ID GROUP BY 1 ON DUPLICATE KEY UPDATE total_donors = VALUES(total_donors), total_received = VALUES(total_received); SELECT * FROM Project_Temp; Tests for both are pretty comparable, in the 0.7 - 0.8 seconds range with 1,000 rows. But I'm really concerned about scalability, and I don't want to have to re-engineer everything as my tables grow. What's the best approach?

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  • How can I make this SQL query more efficient? PHP.

    - by Alan Grant
    Hi all, I have a system whereby a user can view categories that they've subscribed to individually, and also those that are available in the region they belong in by default. So, the tables are as follows: Categories UsersCategories RegionsCategories I'm querying the db for all the categories within their region, and also all the individual categories that they've subscribed to. My query is as follows: Select * FROM (categories c) LEFT JOIN users_categories uc on uc.category_id = c.id LEFT JOIN regions_categories rc on rc.category_id = c.id WHERE (rc.region_id = ? OR uc.user_id = ?) At least I believe that's the query, I'm creating it using Cake's ORM layer, so the exact one is: $conditions = array( array( "OR" => array ( 'RegionsCategories.region_id' => $region_id, 'UsersCategories.user_id' => $user_id ) )); $this->find('all', $conditions); This turns out to be incredibly slow (sometimes around 20 seconds or so. Each table has around 5,000 rows). Is my design at fault here? How can I retrieve both the users' individual categories and those within their region all in one query without it taking ages? Thanks!

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  • Group / User based security. Table / SQL question

    - by Brett
    Hi, I'm setting up a group / user based security system. I have 4 tables as follows: user groups group_user_mappings acl where acl is the mapping between an item_id and either a group or a user. The way I've done the acl table, I have 3 columns of note (actually 4th one as an auto-id, but that is irrelevant) col 1 item_id (item to access) col 3 user_id (user that is allowed to access) col 3 group_id (group that is allowed to access) So for example item1, peter, , item2, , group1 item3, jane, , so either the acl will give access to a user or a group. Any one line in the ACL table with either have an item - user mapping, or an item group. If I want to have a query that returns all objects a user has access to, I think I need to have a SQL query with a UNION, because I need 2 separate queries that join like.. item - acl - group - user AND item - acl - user This I guess will work OK. Is this how its normally done? Am I doing this the right way? Seems a little messy. I was thinking I could get around it by creating a single user group for each person, so I only ever deal with groups in my SQL, but this seems a little messy as well..

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  • Performance impact when using XML columns in a table with MS SQL 2008

    - by Sam Dahan
    I am using a simple table with 6 columns, 3 of which are of XML type, not schema-constrained. When the table reaches a size around 120,000 or 150,000 rows, I see a dramatic performance cost in doing any query in the table. For comparison, I have another table, which grows in size at about the same rate, but only contain scalar types (int, datetime, a few float columns). That table performs perfectly fine even after 200,000 rows. And by the way, I am not using XQuery on the xml columns, i am only using regular SQL query statements. Some specifics: both tables contain a DateTime field called SampleTime. a statement like (it's in a stored procedure but I show you the actual statement) SELECT MAX(sampleTime) SampleTime FROM dbo.MyRecords WHERE PlacementID=@somenumber takes 0 seconds on the table without xml columns, and anything from 13 to 20 seconds on the table with XML columns. That depends on which drive I set my database on. At the moment it sits on a different spindle (not C:) and it takes 13 seconds. Has anyone seen this behavior before, or have any hint at what I am doing wrong? I tried this with SQL 2008 EXPRESS and the full-blown SQL Server 2008, that made no difference. Oh, one last detail: I am doing this from a C# application, .NET 3.5, using SqlConnection, SqlReader, etc.. I'd appreciate some insight into that, thanks! Sam

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  • Process-to-port mapping with SNMP and/or wmi/wmic in java

    - by Niddy888
    I'm trying to use SNMP to map outgoing ports on my host computer with the application running on the computer that is responsible for that communication. When running "netstat -ano" I get access to Protocol, Local Address (with port), Foreign Address (with port), State and PID. But I want to do this entirely without having to execute "cmd" from Java. By using SNMP OID: .1.3.6.1.2.1.25.4 (.iso.org.dod.internet.mgmt.mib-2.host.hrSWRun) I get access to PID (ex. 1704), Name (ex. cmd.exe), Path (ex. C:\Windows\system32) among others. There is an SNMP OID: .1.3.6.1.2.1.6.13 (.iso.org.dod.internet.mgmt.mib-2.tcp.tcpConnTable) that give you access to TCP connection state, local address, local port, remote address, remote port. But NO PID. So to sum up. My question again: Is there a way to "map" these tables together? Either directly in SNMP with other OID's or in conjunction with WMI / WMIC?

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  • Best practice - logging events (general) and changes (database)

    - by b0x0rz
    need help with logging all activities on a site as well as database changes. requirements: * should be in database * should be easily searchable by initiator (user name / session id), event (activity type) and event parameters i can think of a database design but either it involves a lot of tables (one per event) so i can log each of the parameters of an event in a separate field OR it involves one table with generic fields (7 int numeric and 7 text types) and log everything in one table with event type field determining what parameter got written where (and hoping that i don't need more than 7 fields of a certain type, or 8 or 9 or whatever number i choose)... example of entries (the usual things): [username] login failed @datetime [username] login successful @datetime [username] changed password @datetime, estimated security of password [low/ok/high/perfect] @datetime [username] clicked result [result number] [result id] after searching for [search string] and got [number of results] @datetime [username] clicked result [result number] [result id] after searching for [search string] and got [number of results] @datetime [username] changed profile name from [old name] to [new name] @datetime [username] verified name with [credit card type] credit card @datetime datbase table [table name] purged of old entries @datetime via automated process etc... so anyone dealt with this before? any best practices / links you can share? i've seen it done with the generic solution mentioned above, but somehow that goes against what i learned from database design, but as you can see the sheer number of events that need to be trackable (each user will be able to see this info) is giving me headaches, BUT i do LOVE the one event per table solution more than the generic one. any thoughts? edit: also, is there maybe an authoritative list of such (likely) events somewhere? thnx stack overflow says: the question you're asking appears subjective and is likely to be closed. my answer: probably is subjective, but it is directly related to my issue i have with designing a database / writing my code, so i'd welcome any help. also i tried narrowing down the ideas to 2 so hopefully one of these will prevail, unless there already is an established solution for these kinds of things.

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  • stackoverflow tags and related tags

    - by parminder
    Hi Experts, I am working on a website where a user can add tags to their posted books. It is similar to stackover flow, but I am keeping my tags in differnt table. so here are the tables/class in linq to entities. Books { bookId, Title } Tags { Id Tag } BooksTags { Id BookId TagId } Here are few sample records. Books BookId Title 113421 A 113422 B Tags Id Tag 1 ASP 2 C# 3 CSS 4 VB 5 VB.NET 6 PHP 7 java 8 pascal BooksTags Id BookId TagId 1 113421 1 2 113421 2 3 113421 3 4 113421 4 5 113422 1 6 113422 4 7 113422 8 Question 1 : I need to write something in linq to entities queries which gives me data according to the tags say if I want bookIds where tagid =1 it should return bookid 113421 and 113422 as it exists in both the books, but If I ask data for tags 1 and 2 it should return only book 113421 as that is the only book where both the tags are present. Question 2 : I need tags and their count too to show in related tags, so in first case my related tags class should have following result. RelatedTags Tag Count 2 1 3 1 4 2 8 1 in the second case when two tags are requested the result should be like RelatedTags Tag Count 3 1 4 1 I have get the first thing working by converting a sql query in linqer, but that seems like a hell. so want to know if there is any better idea. I have used dyanmic where clause to include two tags. So if someone can help. It will be much appreciated. Thanks Parminder

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  • Constructor and Destructors in C++ [Not a question] [closed]

    - by Jack
    I am using gcc. Please tell me if I am wrong - Lets say I have two classes A & B class A { public: A(){cout<<"A constructor"<<endl;} ~A(){cout<<"A destructor"<<endl;} }; class B:public A { public: B(){cout<<"B constructor"<<endl;} ~B(){cout<<"B destructor"<<endl;} }; 1) The first line in B's constructor should be a call to A's constructor ( I assume compiler automatically inserts it). Also the last line in B's destructor will be a call to A's destructor (compiler does it again). Why was it built this way? 2) When I say A * a = new B(); compiler creates a new B object and checks to see if A is a base class of B and if it is it allows 'a' to point to the newly created object. I guess that is why we don't need any virtual constructors. ( with help from @Tyler McHenry , @Konrad Rudolph) 3) When I write delete a compiler sees that a is an object of type A so it calls A's destructor leading to a problem which is solved by making A's destructor virtual. As user - Little Bobby Tables pointed out to me all destructors have the same name destroy() in memory so we can implement virtual destructors and now the call is made to B's destructor and all is well in C++ land. Please comment.

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  • Hibernate Query for a List of Objects that matches a List of Objects' ids

    - by sal
    Given a classes Foo, Bar which have hibernate mappings to tables Foo, A, B and C public class Foo { Integer aid; Integer bid; Integer cid; ...; } public class Bar { A a; B b; C c; ...; } I build a List fooList of an arbitrary size and I would like to use hibernate to fetch List where the resulting list will look something like this: Bar[1] = [X1,Y2,ZA,...] Bar[2] = [X1,Y2,ZB,...] Bar[3] = [X1,Y2,ZC,...] Bar[4] = [X1,Y3,ZD,...] Bar[5] = [X2,Y4,ZE,...] Bar[6] = [X2,Y4,ZF,...] Bar[7] = [X2,Y5,ZG,...] Bar[8] = ... Where each Xi, Yi and Zi represents a unique object. I know I can iterate fooList and fetch each List and call barList.addAll(...) to build the result list with something like this: List<bar> barList.addAll(s.createQuery("from Bar bar where bar.aid = :aid and ... ") .setEntity("aid", foo.getAid()) .setEntity("bid", foo.getBid()) .setEntity("cid", foo.getCid()) .list(); ); Is there any easier way, ideally one that makes better use of hibernate and make a minimal number of database calls? Am I missing something? Is hibernate not the right tool for this?

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  • Oracle ODBC x64 - getting 0 when selecting a number(9) column

    - by MatsL
    I'm having a really weird problem with a third party web service that uses an ODBC connection to Oracle 10.2.0.3.0. I've written a .NET client that generates the same SQL as the web service so I can find out what's going on. The web service is hosted by IIS 6 that's in x64 mode so we use Oracle x64 client. The oracle client version is 10.2.0.1.0. I have a table that looks like this (I've removed some columns and names): SQL> describe tablename; Name Null? Type ----------------------------------------- -------- ---------------------------- KOD VARCHAR2(30) ORDNING NUMBER(5) AVGIFT NUMBER(9) I then in SQL*Plus issue the following statement: SELECT KOD as kod, AVGIFT as riskPoang FROM tablename Where upper(KODTYP) = 'OBJLIVSV_RISKVERKSAMTYP' ORDER BY ORDNING And I get the following result: KOD RISKPOANG ------------------------------ ---------- Hög risk 55 Mellan risk 35 Låg risk 15 Mycket låg risk 5 But when I execute the exact same SQL using the same DSN on the same machine I get this: Values Kod: Hög risk RiskPoäng: 0 Kod: Mellan risk RiskPoäng: 0 Kod: Låg risk RiskPoäng: 0 Kod: Mycket låg risk RiskPoäng: 0 If I first cast the number to varchar and then back again to number, like this: SELECT KOD as kod, to_number(to_char(AVGIFT, '99'), '9999999999') as riskPoang FROM tablename Where upper(KODTYP) = 'OBJLIVSV_RISKVERKSAMTYP' ORDER BY ORDNING I get the correct result: Values Kod: Hög risk RiskPoäng: 55 Kod: Mellan risk RiskPoäng: 35 Kod: Låg risk RiskPoäng: 15 Kod: Mycket låg risk RiskPoäng: 5 Has anyone else experiences this? It's incredibly annoying and I'm completely stuck and not sure what to do next. We have a third party web service that use these tables so I must get the original SQL-statement to work since I can't modify its code. And pointers are greatly appreciated! :-) Best regards, Mats

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  • Yii CGridView and dropdown filter

    - by Dmitriy Gunchenko
    I created dropdown filter, it's display, but don't worked right. As I anderstand trouble in search() method view: $this->widget('zii.widgets.grid.CGridView', array( 'dataProvider'=>$model->search(), 'filter' => $model, 'columns'=>array( array( 'name' => 'client_id', 'filter' => CHtml::listData(Client::model()->findAll(), 'client_id', 'name'), 'value'=>'$data->client->name' ), 'task' ) )); I have to tables, and they relations are shown down model: public function relations() { // NOTE: you may need to adjust the relation name and the related // class name for the relations automatically generated below. return array( 'client' => array(self::BELONGS_TO, 'Client', 'client_id'), ); } public function search() { // Warning: Please modify the following code to remove attributes that // should not be searched. $criteria=new CDbCriteria; $criteria->with = array('client'); $criteria->compare('task_id',$this->task_id); $criteria->compare('client_id',$this->client_id); $criteria->compare('name',$this->client->name); $criteria->compare('task',$this->task,true); $criteria->compare('start_date',$this->start_date,true); $criteria->compare('end_date',$this->end_date,true); $criteria->compare('complete',$this->complete); return new CActiveDataProvider($this, array( 'criteria'=>$criteria, )); }

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  • using dummy row with NOT NULL to solve DEFAULT NULL

    - by Tony38
    I know having DEFAULT NULLS is not a good practice but I have many optional lookup values which are FK in the system so to solve this issue here is what i am doing: I use NOT NULL for every FK / lookup colunms. I have the first row in every lookup table which is PK id = 1 as a dummy row with just "none" in all the columns. This way I can use NOT NULL in my schema and if needed reference to the none row values PK =1 for FKs which do not have any lookup value. Is this a good design or any other work arounds? EDIT: I have: Neighborhood table Postal table. Every neighborhood has a city, so the FK can be NOT NULL. But not every postal code belongs to a neighborhood. Some do, some don't depending on the country. So if i use NOT NULL for the FK between postal and neighborhood then I will be screwed as there has to be some value entered. So what i am doing in essence is: have a row in every table to be a dummy row just to link the FKs. This way row one in neighborhood table will be: n_id = 1 name =none etc... In postal table I can have: postal_code = 3456A3 FK (city) = Moscow FK (neighborhood_id)=1 as a NOT NULL. If I don't have a dummy row in the neighborhood lookup table then I have to declare FK (neighborhood_id) as a Default null column and store blanks in the table. This is an example but there is a huge number of values which will have blanks then in many tables.

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  • ASP.net MVC Linq-To-SQL Many-To-Many Field Binding

    - by user336858
    Hi there, The short version of this question is "Is there a way to gracefully handle database insertion for an object that has a many-to-many field that has been set up in a partial class?" Apologies if it's been asked before. Example Suppose I have a typical MVC setup with the tables: Posts {PostID, ...} Categories {CategoryID, ...} A post can have more than one category, and a category can identify more than one post. Thus suppose further that I need an extra table: PostCategories {PostID, CategoryID, ...} This handles the many-to-many relationship between posts and categories. As far as I know, there's no way to do this in Linq-to-SQL right now so I have to shoehorn it in by adding a partial Post class to the project to add that functionality. Something like: public partial class Post { public IEnumerable<Category> Categories{ get { ... } set { ... } } } So I can now create a "Create" view that automatically populates a "Categories" UI item. This is where the trouble starts. So here's my question: How do you get automatic object model binding to work cleanly with an object that has a many-to-many relationship to control? The workaround that makes many-to-many relationships possible relies on the Post object having a PostID in order to be associated with CategoryID(s), which is only issued after the Post object has been submitted for validation and insertion. Bit of a Catch22 here. Any terminology, links, or tips you can provide would be tremendously helpful!

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  • World's Most Challening MySQL SQL Query (least I think so...)

    - by keruilin
    Whoever answers this question can claim credit for solving the world's most challenging SQL query, according to yours truly. Working with 3 tables: users, badges, awards. Relationships: user has many awards; award belongs to user; badge has many awards; award belongs to badge. So badge_id and user_id are foreign keys in the awards table. The business logic at work here is that every time a user wins a badge, he/she receives it as an award. A user can be awarded the same badge multiple times. Each badge is assigned a designated point value (point_value is a field in the badges table). For example, BadgeA can be worth 500 Points, BadgeB 1000 Points, and so on. As further example, let's say UserX won BadgeA 10 times and BadgeB 5 times. BadgeA being worth 500 Points, and BadgeB being worth 1000 Points, UserX has accumulated a total of 10,000 Points ((10 x 500) + (5 x 1000)). The end game here is to return a list of top 50 users who have accumulated the most badge points. Can you do it?

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