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  • sqlite on iphone can open db but not prepare statements

    - by jan
    I'm brand new to using sqlite so I may have missed something basic. I've created a database and copied it into my app's document's directory. I'm able to open it but when I make a call to sqlite3_prepare_v2 I receive SQLITE_ERROR, "SQL error or missing database". here's my code: sqlite3 *database; if(sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK) { sqlite3_stmt *compiledStatement; NSString *sqlStatement = @"select * from dbname"; int result = sqlite3_prepare_v2(database, [sqlStatement UTF8String], -1, &compiledStatement, nil); ... } the same sql statement works in the terminal. I've found this question in a few places either without answers or with solutions that don't fix my problem. I'm hoping someone here will be able to help. Thanks.

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  • Save blob to DB using hibernate

    - by Link123
    Hey! I tried save file to MySQL using blob with hibernate3. But I always have java.lang.UnsupportedOperationException: Blob may not be manipulated from creating session org.hibernate.lob.BlobImpl.excep(BlobImpl.java:127) Here some code. package com.uni.domain; public class File extends Identifier { private byte[] data; private String contentType; public byte[] getData() { return data; } public File() {} public void setData(byte[] photo) { this.data = photo; } public boolean isNew() { return true; } public String getContentType() { return contentType; } public void setContentType(String contentType) { this.contentType = contentType; } } package com.uni.domain; import org.hibernate.Hibernate; import org.hibernate.HibernateException; import org.hibernate.usertype.UserType; import java.io.InputStream; import java.io.OutputStream; import java.io.Serializable; import java.sql.*; import java.util.Arrays; public class PhotoType implements UserType { public int[] sqlTypes() { return new int[]{Types.BLOB}; } public Class returnedClass() { return byte[].class; } public boolean equals(Object o, Object o1) throws HibernateException { return Arrays.equals((byte[]) o, (byte[]) o1); } public int hashCode(Object o) throws HibernateException { return o.hashCode(); } public Object nullSafeGet(ResultSet resultSet, String[] strings, Object o) throws HibernateException, SQLException { Blob blob = resultSet.getBlob(strings[0]); return blob.getBytes(1, (int) blob.length()); } public void nullSafeSet(PreparedStatement st, Object value, int index) throws HibernateException, SQLException { st.setBlob(index, Hibernate.createBlob((byte[]) value)); } public Object deepCopy(Object value) { if (value == null) return null; byte[] bytes = (byte[]) value; byte[] result = new byte[bytes.length]; System.arraycopy(bytes, 0, result, 0, bytes.length); return result; } public boolean isMutable() { return true; } public Serializable disassemble(Object o) throws HibernateException { return null; . } public Object assemble(Serializable serializable, Object o) throws HibernateException { return null; . } public Object replace(Object o, Object o1, Object o2) throws HibernateException { return null; . } <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping package="com.uni.domain"> <class name="com.uni.domain.File"> <id name="id"> <generator class="native"/> </id> <property name="data" type="com.uni.domain.FleType"/> <property name="contentType"/> </class> </hibernate-mapping> Help me please. Where I’m wrong?

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  • SSRS - Oracle DB, Passing Date parameter

    - by davidl98
    Using SSRS with an Oracle Database. I need to prompt the user when running the report to enter a date for report. What is the best way to add in the parameter in my SSRS Report. Having problem finding the right date format. under the "Report Parameter" menu, I have setup the Report Parameters using the DateTime Datatype. Keep getting this error "ORA-01843: Not a Valid Month" Thank you for your help. Select a.OPR_Name, a.OPR, a.Trans_Desc, a.Trans_Start_Date, Cast(a.S_Date as date) as S_Date, Sum(a.Duration) as T From ( Select US_F.OPR_Name, ITH_F.OPR, ITH_F.ITH_RID, ITH_F.TRANSACT, Transact.DESC_1 as Trans_Desc, To_CHAR(ITH_F.Start_Time,'DD-Mon-YY') as Trans_Start_Date, To_CHAR(ITH_F.Start_Time,'MM/DD/YYYY') as S_Date, Substr(To_CHAR(ITH_F.Start_Time,'HH24:MI'),1,6) as Start_Time, To_CHAR(ITH_F.End_Time,'DD-Mon-YY') as Trans_End_Date, Substr(To_CHAR(ITH_F.End_Time,'HH24:MI'),1,6) as End_Time, Cast(Case When To_CHAR(ITH_F.Start_Time,'DD-Mon-YY') = To_CHAR(ITH_F.End_Time,'DD-Mon-YY') Then (((To_CHAR(ITH_F.End_Time,'SSSSS') - To_CHAR(ITH_F.Start_Time,'SSSSS')) / 60))/60 Else ((86399 - (To_CHAR(ITH_F.Start_Time,'SSSSS')) + To_CHAR(ITH_F.End_Time,'SSSSS'))/60)/60 End as Decimal(3,1)) as Duration from Elite_76_W1.ITH_F Left Join Elite_76_W1.Transact on Transact.Transact = ITH_F.Transact Left Join Elite_76_W1.US_F on US_F.OPR = ITH_F.OPR Where ITH_F.TRANSACT not in ('ASN','QC','LGOT') ) a Where a.S_Date = @Event_Date Having Sum(a.Duration) < 0 Group By a.OPR_Name, a.OPR, a.Trans_Desc, a.Trans_Start_Date, a.S_Date Order by a.OPR_Name

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  • Best Practise to populate Fact and Dimension Tables from Transactional Flat DB

    - by alex25
    Hi! I want to populate a star schema / cube in SSIS / SSAS. I prepared all my dimension tables and my fact table, primary keys etc. The source is a 'flat' (item level) table and my problem is now how to split it up and get it from one into the respective tables. I did a fair bit of googling but couldn't find a satisfying solution to the problem. One would imagine that this is a rather common problem/situation in BI development?! Thanks, alexl

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  • Atomikos with Hibernate will exhaust db connections

    - by peter
    I am testing an application (Spring 2.5, Hibernate 3.5.0 Beta, Atomikos 3.6.2, and Postgreql 8.4.2) with the configuration for the DAO listed below. The problem that I see is that the pool of 10 connections with the dataSource gets exhausted after the 10's transaction. I know 'hibernate.connection.release_mode' has no effect unless the session is obtained with openSession rather then using a contextual session. I am wandering if anyone has found a way to instruct atomikos code to release connections after any transaction. Thank you Peter <bean id="dataSource" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init" destroy-method="close"> <property name="uniqueResourceName"><value>XADBMS</value></property> <property name="xaDataSourceClassName"> <value>org.postgresql.xa.PGXADataSource</value> </property> <property name="xaProperties"> <props> <prop key="databaseName">${jdbc.name}</prop> <prop key="serverName">${jdbc.server}</prop> <prop key="portNumber">${jdbc.port}</prop> <prop key="user">${jdbc.username}</prop> <prop key="password">${jdbc.password}</prop> </props> </property> <property name="poolSize"><value>10</value></property> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> <property name="dataSource"> <ref bean="dataSource" /> </property> <property name="mappingResources"> <list> <value>Abc.hbm.xml</value> </list> </property> <property name="hibernateProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</prop> <prop key="hibernate.show_sql">on</prop> <prop key="hibernate.format_sql">true</prop> <prop key="hibernate.connection.isolation">3</prop> <prop key="hibernate.current_session_context_class">jta</prop> <prop key="hibernate.transaction.factory_class">org.hibernate.transaction.JTATransactionFactory</prop> <prop key="hibernate.transaction.manager_lookup_class">com.atomikos.icatch.jta.hibernate3.TransactionManagerLookup</prop> <prop key="hibernate.connection.release_mode">auto</prop> <prop key="hibernate.current_session_context_class">org.hibernate.context.JTASessionContext</prop> <prop key="hibernate.transaction.auto_close_session">true</prop> </props> </property> </bean> <!-- Transaction definition here --> <bean id="userTransactionService" class="com.atomikos.icatch.config.UserTransactionServiceImp" init-method="init" destroy-method="shutdownForce"> <constructor-arg> <props> <prop key="com.atomikos.icatch.service"> com.atomikos.icatch.standalone.UserTransactionServiceFactory </prop> </props> </constructor-arg> </bean> <!-- Construct Atomikos UserTransactionManager, needed to configure Spring --> <bean id="AtomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager" init-method="init" destroy-method="close" depends-on="userTransactionService"> <property name="forceShutdown" value="false" /> </bean> <!-- Also use Atomikos UserTransactionImp, needed to configure Spring --> <bean id="AtomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp" depends-on="userTransactionService"> <property name="transactionTimeout" value="300" /> </bean> <!-- Configure the Spring framework to use JTA transactions from Atomikos --> <bean id="txManager" class="org.springframework.transaction.jta.JtaTransactionManager" depends-on="userTransactionService"> <property name="transactionManager" ref="AtomikosTransactionManager" /> <property name="userTransaction" ref="AtomikosUserTransaction" /> </bean> <!-- the transactional advice (what 'happens'; see the <aop:advisor/> bean below) --> <tx:advice id="txAdvice" transaction-manager="txManager"> <tx:attributes> <!-- all methods starting with 'get' are read-only --> <tx:method name="get*" read-only="true" propagation="REQUIRED"/> <!-- other methods use the default transaction settings (see below) --> <tx:method name="*" propagation="REQUIRED"/> </tx:attributes> </tx:advice> <aop:config> <aop:advisor pointcut="execution(* *.*.AbcDao.*(..))" advice-ref="txAdvice"/> </aop:config> <!-- DAO objects --> <bean id="abcDao" class="test.dao.impl.HibernateAbcDao" scope="singleton"> <property name="sessionFactory" ref="sessionFactory"/> </bean>

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  • Error when running rake db:create

    - by Amy
    Hi, I am trying to setup an ror app but I keep getting this error. Any ideas as to what may be causing the problem? /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require' /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:156:in `require' /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:521:in `new_constants_in' /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:156:in `require' /home/projects/testproject/lib/tasks/more_tasks.rake:3 /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:145:in `load_without_new_constant_marking' /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:145:in `load' /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:521:in `new_constants_in' /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:145:in `load' /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/tasks/rails.rb:9 /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/tasks/rails.rb:9:in `each' /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/tasks/rails.rb:9 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require' /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' /home/projects/testproject/Rakefile:10 /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2383:in `load' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2383:in `raw_load_rakefile' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2017:in `load_rakefile' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2016:in `load_rakefile' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2000:in `run' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/lib/rake.rb:1998:in `run' /usr/lib/ruby/gems/1.8/gems/rake-0.8.7/bin/rake:31 /usr/bin/rake:19:in `load' /usr/bin/rake:19

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  • Difficulty setting ArrayList to java.sql.Blob to save in DB using hibernate

    - by me_here
    I'm trying to save a java ArrayList in a database (H2) by setting it as a blob, for retrieval later. If this is a bad approach, please say - I haven't been able to find much information on this area. I have a column of type Blob in the database, and Hibernate maps to this with java.sql.Blob. The code I'm struggling with is: Drawings drawing = new Drawings(); try { ByteArrayOutputStream bos = new ByteArrayOutputStream(); ObjectOutputStream oos = null; oos = new ObjectOutputStream(bos); oos.writeObject(plan.drawingPane21.pointList); byte[] buff = bos.toByteArray(); Blob drawingBlob = null; drawingBlob.setBytes(0, buff); drawing.setDrawingObject(drawingBlob); } catch (Exception e){ System.err.println(e); } The object I'm trying to save into a blob (plan.drawingPane21.pointList) is of type ArrayList<DrawingDot>, DrawingDot being a custom class implementing Serializable. My code is failing on the line drawingBlob.setBytes(0, buff); with a NullPointerException. Help appreciated.

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  • Connecting to external MySQL DB from a web server not running MySQL

    - by jrb04c
    While I've been working with MySQL for years, this is the first time I've run across this very newbie-esq issue. Due to a client demand, I must host their website files (PHP) on a IIS server that is not running MySQL (instead, they are running MSSQL). However, I have developed the site using a MySQL database which is located on an external host (Rackspace Cloud). Obviously, my mysql_connect function is now bombing because MySQL is not running on localhost. Question: Is it even possible to hit an external MySQL database if localhost is not running MySQL? Apologies for the rookie question, and many thanks in advance.

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  • MD5 hash with salt for keeping password in DB in C#

    - by abatishchev
    Could you please advise me some easy algorithm for hashing user password by MD5, but with salt for increasing reliability. Now I have this one: private static string GenerateHash(string value) { var data = System.Text.Encoding.ASCII.GetBytes(value); data = System.Security.Cryptography.MD5.Create().ComputeHash(data); return Convert.ToBase64String(data); }

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  • Receiving DB update events in .NET from SQLite

    - by Dan Tao
    I've recently discovered the awesomeness of SQLite, specifically the .NET wrapper for SQLite at http://sqlite.phxsoftware.com/. Now, suppose I'm developing software that will be running on multiple machines on the same network. Nothing crazy, probably only 5 or 6 machines. And each of these instances of the software will be accessing an SQLite database stored in a file in a shared directory (is this a bad idea? If so, tell me!). Is there a way for each instance of the app to be notifiied if one instance updates the database file? One obvious way would be to use the FileSystemWatcher class, read the entire database into a DataSet, and then ... you know ... enumerate through the entire thing to see what's new ... but yeah, that seems pretty idiotic, actually. Is there such a thing as a provider of SQLite updates? Does this even make sense as a question? I'm also pretty much a newbie when it comes to ADO.NET, so I might be approaching the problem from the entirely wrong angle.

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  • Light-weight client/server DB?

    - by OverTheRainbow
    Hello, (This question falls between programming and finding a tool, so I guess I'll ask here in SO since it has more activity than SuperUser.) I like the simplicity of SQLite, but by design, it doesn't support concurrent access. The apps I write don't have heavy needs, so I'd like to avoid heavier solutions like MySQL that are more difficult to deploy (remote customers with usually no computer personnel). Does someone know of a good solution that would offer the following features? Client available for VB.Net applications The server itself doesn't have to be a .Net application. Actually, I'd rather a bare-metal server so that it can run even on embedded Linux hosts with less RAM/CPU than regular PC's Easy install: the client part should either be statically linked inside the client application or be available as a single DLL, and the server should just be a single EXE listening for queries, à la Fossil (http://www.fossil-scm.org) clients can locate the server on the LAN by broadcasting data picked up by the server, so users don't have to write down the IP address and paste it into each client open-source, or moderately priced closed-source Thank you.

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  • fast retrieval from MYSQL DB

    - by trojanwarrior3000
    I have a table of users - It contains around millions of rows (user-id is the primary key). I just want to retrieve user-id and their joining date. using "select user-id,joining date from table user" requires lot of time.Is there a fast way to query/retrieve the same data from this table?

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  • Setting up a multi-site CMS, collecting thoughts about the DB schema

    - by Ben Fransen
    Hello all, I'm collecting some thoughts about creating a multisite CMS. In my opinion there are two major approaches. All data is stored into 1 database, giving me the advantage of single point of updates; Seperated databases, so each client has its own database. Giving me the advantage to measure bandwith. Option 1 gives me the disadvantage of measuring bandwith while option is giving me the disadvantage of a single point of update structure. Are there any generic approaches for creating a sort of update system? So my clients can download a small package (maybe a zip with a conf file to tell the updatescript where to put all the files and how to extend the database??) Do you guys have some thougths about the best solution for a situation like this? I have my own webserver, full access to all resources and I'm developing in PHP with MySQL as DBMS. I hope to hear from you and I surely appreciate any effort you make to help me further! Greets from Holland, Ben Fransen

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  • How to transfer SQLite db to web server

    - by Shane
    Hi, I have an application that creates an SQLite database and saves information to it over the course of a day. At the end of the day i want to export this database to a web server. Could anyone point me in the right direction for this? Should I use httppost or put. I have researched this myself online but there seems to be so many different ways to explore. The server side does not exist yet either. I have access to an apache server so i am hoping to use that. Could anyone advise me the best/most simple way to do this? Thanks

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  • Save all xml nodes to db without looping through it

    - by AndreMiranda
    I have this xml: <Path> <Record> <ID>6534808</ID> <Distance>1.05553036073736</Distance> </Record> <Record> <ID>6542471</ID> <Distance>1.05553036073736</Distance> </Record> ... and about more 500 nodes </Path> And I'm using the code below to get all "Record" nodes: XmlNodeList paths = xDoc.SelectNodes("//Record"); And, after that, I save each record to database. But, the problem is that I'm using a foreach to loop through this nodes and the count of this nodes may be more than 500, sometimes it gets up to 1000 "Records" node. And this gets too long... Is there a way to save all of these nodes without looping through it? Thanks!!

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  • How update DB table with DataSet

    - by Paul
    I am begginer with ADO.NET , I try update table with DataSet. O client side I have dataset with one table. I send this dataset on service side (it is ASP.NET Web Service). On Service side I try update table in database, but it dont 't work. public bool Update(DataSet ds) { SqlConnection conn = null; SqlDataAdapter da = null; SqlCommand cmd = null; try { string sql = "UPDATE * FROM Tab1"; string connStr = WebConfigurationManager.ConnectionStrings["Employees"].ConnectionString; conn = new SqlConnection(connStr); conn.Open(); cmd=new SqlCommand(sql,conn); da = new SqlDataAdapter(sql, conn); da.UpdateCommand = cmd; da.Update(ds.Tables[0]); return true; } catch (Exception ex) { throw ex; } finally { if (conn != null) conn.Close(); if (da != null) da.Dispose(); } } Where can be problem?

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  • DB comparison tools

    - by Dimi Toulakis
    Has someone experience with database comparison tools? Which one you would recommend? We are currently using "SQLCompare" from Redgate, but I am curious to know if there are better tools on the market. The main requirement is that they should be able to compare scripts folder against a live database. Thanks, Dimi

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  • Creating Membership Tables, SPROCs, Views in Attached DB

    - by azamsharp
    I have AdventureWorks database mdf file in my VS 2010 project. Is there anyway I can create Membership tables inside my AdventureWorks database. I know I can detach the database attach in SQL SERVER 2008. Create the tables and then detach. But I don't have SQL SERVER 2008 and I want to see if this can be done using command line tool. I tried this but no use: aspnet_regsql.exe -d AdventureWorks.mdf -A mr -E -S .\SQLEXPRESS Update: If I right click and see the properties of the AdventureWorks.mdf database then it shows the name as "C4BE6C8DA139A060D14925377A7E63D0_64A_10\ADVENTUREWORKSWEBFORMS\ADVENTUREWORKSWEBFORMS\ADVENTUREWORKS\APP_DATA\ADVENTUREWORKS.MDF" This is interesting!

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  • Microsoft OLE DB Provider for SQL Server error '80040e14' Could not find stored procedure

    - by BBlake
    I am migrating a classic ASP web app to new servers. The database back end is migrating from SQL Server 2000 to SQL Server 2008, and the app is moving from Win2000 x86 to Win2003R2 x64. I am getting the above error on every single stored procedure call within the application. I have verified: Yes, the SQL user is set up, using correct username and password Yes, the SQL user has execute permissions on the stored procedures in the database Yes, I have updated the TypeLib references to the new UUID Yes, I have logged into the database via SSMS with the SQL user id and it can see and execute the stored procedures just fine in SSMS, but not from the web app. Yes, the SQL user has the database set as its default database. The most frustrating thing is it works fine on the DEV server, but not on the production server. I have gone through every IIS setting 5 or 6 times and the web app is set up precisely the same in both environments. The only difference is the database server name in the connection string (DEV vs prod) EDIT: I have also tried pointing the prod web box at the dev database server and get the same error so I'm fairly sure the issue isn't on the database side.

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  • rake db:migrate gives a uninitialized class variable @@configuration in Rails error

    - by PK
    uninitialized class variable @@configuration in Rails /usr/lib/ruby/gems/1.8/gems/rails-2.1.0/lib/initializer.rb:19:in `configuration' /usr/lib/ruby/gems/1.8/gems/thoughtbot-factory_girl-1.2.2/lib/factory_girl.rb:24 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:36:in `gem_original_require' This is the initial part of the enviroment.rb: RAILS_GEM_VERSION = '2.1.0' unless defined? RAILS_GEM_VERSION require File.join(File.dirname(__FILE__), 'boot') Rails::Initializer.run do |config| config.gem "oauth", :version => "0.2.7", :lib => "oauth"

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  • useing my own db info to replace parts of a url and open in a iframe

    - by Morpheus Lucid
    print ("http://maps.google.com/maps/api/staticmap?center=");echo $City;print (",");echo $City;print (","); echo $State;print ("&zoom=14&size=500x500&maptype=roadmap&markers=color:blue|label:S|"); echo $Latitude;print (",");echo $Longitude;print ("&sensor=false")"); when page is loaded it prints right but would like to take the results from this and put into a iframe so when page loads it shows the map of the entry

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  • C# check age of db Item

    - by Jacob Huggart
    Hello All, I am using C# to send an email with an encrypted link. The encrypted portion of the link contains a time stamp that needs to be used to verify if the link is more than 48 hours old. How do I compare an old time to the current time and find out if the old time is more than 48 hours ago? This is what I have now: var hours = DateTime.Now.Ticks - data.DTM.Value.Ticks; //data.DTM = stored time stamp if (hours.CompareTo(48) > 1) //if link is more than 48 hours old, deny access. return View("LinkExpired"); } Comparing ticks seems like it's a very backwards way to do it and I know that the hours.CompareTo would have to be adjusted if I stick with comparing ticks. How can I just get a value for the number of hours that have passed?

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  • Building a many-to-many db schema using only an unpredictable number of foreign keys

    - by user1449855
    Good afternoon (at least around here), I have a many-to-many relationship schema that I'm having trouble building. The main problem is that I'm only working with primary and foreign keys (no varchars or enums to simplify things) and the number of many-to-many relationships is not predictable and can increase at any time. I looked around at various questions and couldn't find something that directly addressed this issue. I split the problem in half, so I now have two one-to-many schemas. One is solved but the other is giving me fits. Let's assume table FOO is a standard, boring table that has a simple primary key. It's the one in the one-to-many relationship. Table BAR can relate to multiple keys of FOO. The number of related keys is not known beforehand. An example: From a query FOO returns ids 3, 4, 5. BAR needs a unique key that relates to 3, 4, 5 (though there could be any number of ids returned) The usual join table does not work: Table FOO_BAR primary_key | foo_id | bar_id | Since FOO returns 3 unique keys and here bar_id has a one-to-one relationship with foo_id. Having two join tables does not seem to work either, as it still can't map foo_ids 3, 4, 5 to a single bar_id. Table FOO_TO_BAR primary_key | foo_id | bar_to_foo_id | Table BAR_TO_FOO primary_key | foo_to_bar_id | bar_id | What am I doing wrong? Am I making things more complicated than they are? How should I approach the problem? Thanks a lot for the help.

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