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  • SQL SERVER – Difference Between DATETIME and DATETIME2 – WITH GETDATE

    - by pinaldave
    Earlier I wrote blog post SQL SERVER – Difference Between GETDATE and SYSDATETIME which inspired me to write SQL SERVER – Difference Between DATETIME and DATETIME2. Now earlier two blog post inspired me to write this blog post (and 4 emails and 3 reads from readers). I previously populated DATETIME and DATETIME2 field with SYSDATETIME, which gave me very different behavior as SYSDATETIME was rounded up/down for the DATETIME datatype. I just ran the same experiment but instead of populating SYSDATETIME in this script I will be using GETDATE function. DECLARE @Intveral INT SET @Intveral = 10000 CREATE TABLE #TimeTable (FirstDate DATETIME, LastDate DATETIME2) WHILE (@Intveral > 0) BEGIN INSERT #TimeTable (FirstDate, LastDate) VALUES (GETDATE(), GETDATE()) SET @Intveral = @Intveral - 1 END GO SELECT COUNT(DISTINCT FirstDate) D_FirstDate, COUNT(DISTINCT LastDate) D_LastDate FROM #TimeTable GO SELECT DISTINCT a.FirstDate, b.LastDate FROM #TimeTable a INNER JOIN #TimeTable b ON a.FirstDate = b.LastDate GO SELECT * FROM #TimeTable GO DROP TABLE #TimeTable GO Let us run above script and observe the results. You will find that the values of GETDATE which is populated in both the columns FirstDate and LastDate are very much same. This is because GETDATE is of datatype DATETIME and the precision of the GETDATE is smaller than DATETIME2 there is no rounding happening. In other word, this experiment is pointless. I have included this as I got 4 emails and 3 twitter questions on this subject. If your datatype of variable is smaller than column datatype there is no manipulation of data, if data type of variable is larger than column datatype the data is rounded. Reference: Pinal Dave (http://www.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL DateTime, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Entity Framework version 1- Brief Synopsis and Tips &ndash; Part 1

    - by Rohit Gupta
    To Do Eager loading use Projections (for e.g. from c in context.Contacts select c, c.Addresses)  or use Include Query Builder Methods (Include(“Addresses”)) If there is multi-level hierarchical Data then to eager load all the relationships use Include Query Builder methods like customers.Include("Order.OrderDetail") to include Order and OrderDetail collections or use customers.Include("Order.OrderDetail.Location") to include all Order, OrderDetail and location collections with a single include statement =========================================================================== If the query uses Joins then Include() Query Builder method will be ignored, use Nested Queries instead If the query does projections then Include() Query Builder method will be ignored Use Address.ContactReference.Load() OR Contact.Addresses.Load() if you need to Deferred Load Specific Entity – This will result in extra round trips to the database ObjectQuery<> cannot return anonymous types... it will return a ObjectQuery<DBDataRecord> Only Include method can be added to Linq Query Methods Any Linq Query method can be added to Query Builder methods. If you need to append a Query Builder Method (other than Include) after a LINQ method  then cast the IQueryable<Contact> to ObjectQuery<Contact> and then append the Query Builder method to it =========================================================================== Query Builder methods are Select, Where, Include Methods which use Entity SQL as parameters e.g. "it.StartDate, it.EndDate" When Query Builder methods do projection then they return ObjectQuery<DBDataRecord>, thus to iterate over this collection use contact.Item[“Name”].ToString() When Linq To Entities methods do projection, they return collection of anonymous types --- thus the collection is strongly typed and supports Intellisense EF Object Context can track changes only on Entities, not on Anonymous types. If you use a Defining Query for a EntitySet then the EntitySet becomes readonly since a Defining Query is the same as a View (which is treated as a ReadOnly by default). However if you want to use this EntitySet for insert/update/deletes then we need to map stored procs (as created in the DB) to the insert/update/delete functions of the Entity in the Designer You can use either Execute method or ToList() method to bind data to datasources/bindingsources If you use the Execute Method then remember that you can traverse through the ObjectResult<> collection (returned by Execute) only ONCE. In WPF use ObservableCollection to bind to data sources , for keeping track of changes and letting EF send updates to the DB automatically. Use Extension Methods to add logic to Entities. For e.g. create extension methods for the EntityObject class. Create a method in ObjectContext Partial class and pass the entity as a parameter, then call this method as desired from within each entity. ================================================================ DefiningQueries and Stored Procedures: For Custom Entities, one can use DefiningQuery or Stored Procedures. Thus the Custom Entity Collection will be populated using the DefiningQuery (of the EntitySet) or the Sproc. If you use Sproc to populate the EntityCollection then the query execution is immediate and this execution happens on the Server side and any filters applied will be applied in the Client App. If we use a DefiningQuery then these queries are composable, meaning the filters (if applied to the entityset) will all be sent together as a single query to the DB, returning only filtered results. If the sproc returns results that cannot be mapped to existing entity, then we first create the Entity/EntitySet in the CSDL using Designer, then create a dummy Entity/EntitySet using XML in the SSDL. When creating a EntitySet in the SSDL for this dummy entity, use a TSQL that does not return any results, but does return the relevant columns e.g. select ContactID, FirstName, LastName from dbo.Contact where 1=2 Also insure that the Entity created in the SSDL uses the SQL DataTypes and not .NET DataTypes. If you are unable to open the EDMX file in the designer then note the Errors ... they will give precise info on what is wrong. The Thrid option is to simply create a Native Query in the SSDL using <Function Name="PaymentsforContact" IsComposable="false">   <CommandText>SELECT ActivityId, Activity AS ActivityName, ImagePath, Category FROM dbo.Activities </CommandText></FuncTion> Then map this Function to a existing Entity. This is a quick way to get a custom Entity which is regular Entity with renamed columns or additional columns (which are computed columns). The disadvantage to using this is that It will return all the rows from the Defining query and any filter (if defined) will be applied only at the Client side (after getting all the rows from DB). If you you DefiningQuery instead then we can use that as a Composable Query. The Fourth option (for mapping a READ stored proc results to a non-existent Entity) is to create a View in the Database which returns all the fields that the sproc also returns, then update the Model so that the model contains this View as a Entity. Then map the Read Sproc to this View Entity. The other option would be to simply create the View and remove the sproc altogether. ================================================================ To Execute a SProc that does not return a entity, use a EntityCommand to execute that proc. You cannot call a sproc FunctionImport that does not return Entities From Code, the only way is to use SSDL function calls using EntityCommand.  This changes with EntityFramework Version 4 where you can return Scalar Types, Complex Types, Entities or NonQuery ================================================================ UDF when created as a Function in SSDL, we need to set the Name & IsComposable properties for the Function element. IsComposable is always false for Sprocs, for UDF's set this to true. You cannot call UDF "Function" from within code since you cannot import a UDF Function into the CSDL Model (with Version 1 of EF). only stored procedures can be imported and then mapped to a entity ================================================================ Entity Framework requires properties that are involved in association mappings to be mapped in all of the function mappings for the entity (Insert, Update and Delete). Because Payment has an association to Reservation... hence we need to pass both the paymentId and reservationId to the Delete sproc even though just the paymentId is the PK on the Payment Table. ================================================================ When mapping insert, update and delete procs to a Entity, insure that all the three or none are mapped. Further if you have a base class and derived class in the CSDL, then you must map (ins, upd, del) sprocs to all parent and child entities in the inheritance relationship. Note that this limitation that base and derived entity methods must all must be mapped does not apply when you are mapping Read Stored Procedures.... ================================================================ You can write stored procedures SQL directly into the SSDL by creating a Function element in the SSDL and then once created, you can map this Function to a CSDL Entity directly in the designer during Function Import ================================================================ You can do Entity Splitting such that One Entity maps to multiple tables in the DB. For e.g. the Customer Entity currently derives from Contact Entity...in addition it also references the ContactPersonalInfo Entity. One can copy all properties from the ContactPersonalInfo Entity into the Customer Entity and then Delete the CustomerPersonalInfo entity, finall one needs to map the copied properties to the ContactPersonalInfo Table in Table Mapping (by adding another table (ContactPersonalInfo) to the Table Mapping... this is called Entity Splitting. Thus now when you insert a Customer record, it will automatically create SQL to insert records into the Contact, Customers and ContactPersonalInfo tables even though you have a Single Entity called Customer in the CSDL =================================================================== There is Table by Type Inheritance where another EDM Entity can derive from another EDM entity and absorb the inherted entities properties, for example in the Break Away Geek Adventures EDM, the Customer entity derives (inherits) from the Contact Entity and absorbs all the properties of Contact entity. Thus when you create a Customer Entity in Code and then call context.SaveChanges the Object Context will first create the TSQL to insert into the Contact Table followed by a TSQL to insert into the Customer table =================================================================== Then there is the Table per Hierarchy Inheritance..... where different types are created based on a condition (similar applying a condition to filter a Entity to contain filtered records)... the diference being that the filter condition populates a new Entity Type (derived from the base Entity). In the BreakAway sample the example is Lodging Entity which is a Abstract Entity and Then Resort and NonResort Entities which derive from Lodging Entity and records are filtered based on the value of the Resort Boolean field =================================================================== Then there is Table per Concrete Type Hierarchy where we create a concrete Entity for each table in the database. In the BreakAway sample there is a entity for the Reservation table and another Entity for the OldReservation table even though both the table contain the same number of fields. The OldReservation Entity can then inherit from the Reservation Entity and configure the OldReservation Entity to remove all Scalar Properties from the Entity (since it inherits the properties from Reservation and filters based on ReservationDate field) =================================================================== Complex Types (Complex Properties) Entities in EF can also contain Complex Properties (in addition to Scalar Properties) and these Complex Properties reference a ComplexType (not a EntityType) DropdownList, ListBox, RadioButtonList, CheckboxList, Bulletedlist are examples of List server controls (not data bound controls) these controls cannot use Complex properties during databinding, they need Scalar Properties. So if a Entity contains Complex properties and you need to bind those to list server controls then use projections to return Scalar properties and bind them to the control (the disadvantage is that projected collections are not tracked by the Object Context and hence cannot persist changes to the projected collections bound to controls) ObjectDataSource and EntityDataSource do account for Complex properties and one can bind entities with Complex Properties to Data Source controls and they will be tracked for changes... with no additional plumbing needed to persist changes to these collections bound to controls So DataBound controls like GridView, FormView need to use EntityDataSource or ObjectDataSource as a datasource for entities that contain Complex properties so that changes to the datasource done using the GridView can be persisted to the DB (enabling the controls for updates)....if you cannot use the EntityDataSource you need to flatten the ComplexType Properties using projections With EF Version 4 ComplexTypes are supported by the Designer and can add/remove/compose Complex Types directly using the Designer =================================================================== Conditional Mapping ... is like Table per Hierarchy Inheritance where Entities inherit from a base class and then used conditions to populate the EntitySet (called conditional Mapping). Conditional Mapping has limitations since you can only use =, is null and IS NOT NULL Conditions to do conditional mapping. If you need more operators for filtering/mapping conditionally then use QueryView(or possibly Defining Query) to create a readonly entity. QueryView are readonly by default... the EntitySet created by the QueryView is enabled for change tracking by the ObjectContext, however the ObjectContext cannot create insert/update/delete TSQL statements for these Entities when SaveChanges is called since it is QueryView. One way to get around this limitation is to map stored procedures for the insert/update/delete operations in the Designer. =================================================================== Difference between QueryView and Defining Query : QueryView is defined in the (MSL) Mapping File/section of the EDM XML, whereas the DefiningQuery is defined in the store schema (SSDL). QueryView is written using Entity SQL and is this database agnostic and can be used against any database/Data Layer. DefiningQuery is written using Database Lanaguage i.e. TSQL or PSQL thus you have more control =================================================================== Performance: Lazy loading is deferred loading done automatically. lazy loading is supported with EF version4 and is on by default. If you need to turn it off then use context.ContextOptions.lazyLoadingEnabled = false To improve Performance consider PreCompiling the ObjectQuery using the CompiledQuery.Compile method

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  • URL Parts available to URL Rewrite Rules

    - by OWScott
    URL Rewrite is a powerful URL rewriting tool available for IIS7 and newer.  Your rewriting options are almost unlimited, giving you the ability to optimize URLs for search engine optimization (SEO), support multiple domain names on a single site, hiding complex paths and much more. URL Rewrite allows you to use any Server Variable as conditions, and with URL Rewrite 2.0, you can also update them on the fly.  To see all variables available to your site, see this post. An understanding of the parts of a complete URL are essential to working with URL Rewrite, so I’ll include the basics here.  Ruslan Yakushev’s configuration reference was my authoritative source for this. Take this URL for example: The URL is http://www.bing.com/search?q=IIS+url+rewrite The parts of the URL are: http(s)://<host>:<port>/<path>?<querystring> Part Example Server Variable http(s) http SERVER_PORT_SECURE or HTTPS = on/off <host> www.bing.com HTTP_HOST <port> Default is 80 SERVER_PORT <path> search The rule pattern in URL Rewrite <path> /search PATH_INFO <querystring> q=IIS+url+rewrite QUERY_STRING entire URL path with querystring /search?q=IIS+url+rewrite REQUEST_URI It’s important to note that /, : and ? aren’t included in some of the server variables. Understanding which slashes are included is important to creating successful rules.

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  • How to set the service endPoint URI dynamically in SOA Suite 11gR1 by Sylvain Grosjean’s

    - by JuergenKress
    Use Case : This example demonstrates how to get the URI of the backend service from a repository and how to set it dynamically to our partnerLink (dynamicPartnerLink). Implementation steps : Create a dvm file Create a BPEL component Add the endPointURI variable and assign the uri Set the endpointURI property in the invoke activity 1. Create a DVM file : In order to define our repository, we are going to use DVM (Data Value Maps) : For more explanation regarding DVM, you should read this documentation. 2. Create a BPEL Component : First you need to implement the simple bpel process like this : - The AssignPayload is used to set the inputvariable of our invoke activity. - The AssignEndpointURI is used to dynamically set the endPointURI variable from our DVM repository - The invoke activity to call the external service Read the complete article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: human task,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress,Sylvain Grosjean

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  • PHP won't load php.ini

    - by Chuck
    I am racking my brain here and I must be doing something really stupid. I'm trying to setup PHP on Win2008 R2/IIS 7.5. I unpacked php538 into c:\php538 and renamed the php.ini-development to php.ini. Then i tried going to a command prompt and running: c:\php358\php -info I get: Configuration File (php.ini) Path => C:\windows Loaded Configuration File => (none)Scan this dir for additional .ini files => (none) Additional .ini files parsed => (none) Loaded Configuration File => (none) Scan this dir for additional .ini files => (none) Additional .ini files parsed => (none) I have tried using php5217. I tried putting php.ini in c:\windows. I tried creating the PHPRC envrionment variable and pointing it to c:\php358. Every time I have the same problem. PHP does not find or load the ini file. If I run: c:\php358\php -c php.ini -info Then it will load the file. But I shouldn't have to do this for PHP to find the file in the same directory, in the Windows directory, or using the environment variable, so I'm stumped. When I try to run PHP from IIS I get a 500 error and I can only assume at this time it is because it can't find and load the php.ini file correctly. I see similar questions on here, but none seem to address the problem I am having.

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  • A dacpac limitation – Deploy dacpac wizard does not understand SqlCmd variables

    - by jamiet
    Since the release of SQL Server 2012 I have become a big fan of using dacpacs for deploying SQL Server databases (for reasons that I will explain some other day) and I chose to use a dacpac to distribute my recently announced utility sp_ssiscatalog (read: Introducing sp_ssiscatalog (v1.0.0.0)). Unfortunately if you read that blog post you may have taken note of the following: Ordinarily a dacpac can be deployed to a SQL Server from SSMS using the Deploy Dacpac wizard however in this case there is a limitation. Due to sp_ssiscatalog referring to objects in the SSIS Catalog (which it has to do of course) the dacpac contains a SqlCmd variable to store the name of the database that underpins the SSIS Catalog; unfortunately the Deploy Dacpac wizard in SSMS has a rather gaping limitation in that it cannot deploy dacpacs containing SqlCmd variables. I think it is worth calling out this limitation separately in this blog post because its a limitation that all dacpac users need to be aware of. If you try and deploy the dacpac containing sp_ssiscatalog using the wizard in SSMS then this is what you will see: TITLE: Microsoft SQL Server Management Studio ------------------------------ Could not deploy package. (Microsoft.SqlServer.Dac) ------------------------------ ADDITIONAL INFORMATION: Missing values for the following SqlCmd variables:SSISDB. (Microsoft.Data.Tools.Schema.Sql) ------------------------------ BUTTONS: OK ------------------------------ The message is quite correct. The SSDT DB project that I used to build this dacpac *does* have a SqlCmd variable in it called SSISDB: Quite simply, the Dac Deployment wizard in SSMS is not capable of deploying such dacpacs. Your only option for deploying such dacpacs is to use the command-line tool sqlpackage.exe. Generally I use sqlpackage.exe anyway (which is why it has taken me months to encounter the aforementioned problem) and have found it preferable to using a GUI-based wizard. Your mileage may vary. @Jamiet

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  • How to write PowerShell code part 1 (Using external xml configuration file)

    - by ybbest
    In this post, I will show you how to use external xml file with PowerShell. The advantage for doing so is that you can avoid other people to open up your PowerShell code to make the configuration changes; instead all they need to do is to change the xml file. I will refactor my site creation script as an example; you can download the script here and refactored code here. 1. As you can see below, I hard code all the variables in the script itself. $url = "http://ybbest" $WebsiteName = "Ybbest" $WebsiteDesc = "Ybbest test site" $Template = "STS#0" $PrimaryLogin = "contoso\administrator" $PrimaryDisplay = "administrator" $PrimaryEmail = "[email protected]" $MembersGroup = "$WebsiteName Members" $ViewersGroup = "$WebsiteName Viewers" 2. Next, I will show you how to manipulate xml file using PowerShell. You can use the get-content to grab the content of the file. [xml] $xmlconfigurations=get-content .\SiteCollection.xml 3. Then you can set it to variable (the variable has to be typed [xml] after that you can read the content of the xml content, PowerShell also give you nice IntelliSense by press the Tab key. [xml] $xmlconfigurations=get-content .\SiteCollection.xml $xmlconfigurations.SiteCollection $xmlconfigurations.SiteCollection.SiteName 4. After refactoring my code, I can set the variables using the xml file as below. #Set the parameters $siteInformation=$xmlinput.SiteCollection $url = $siteInformation.URL $siteName = $siteInformation.SiteName $siteDesc = $siteInformation.SiteDescription $Template = $siteInformation.SiteTemplate $PrimaryLogin = $siteInformation.PrimaryLogin $PrimaryDisplay = $siteInformation.PrimaryDisplayName $PrimaryEmail = $siteInformation.PrimaryLoginEmail $MembersGroup = "$WebsiteName Members" $ViewersGroup = "$WebsiteName Viewers"

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  • Clustering Basics and Challenges

    - by Karoly Vegh
    For upcoming posts it seemed to be a good idea to dedicate some time for cluster basic concepts and theory. This post misses a lot of details that would explode the articlesize, should you have questions, do not hesitate to ask them in the comments.  The goal here is to get some concepts straight. I can't promise to give you an overall complete definitions of cluster, cluster agent, quorum, voting, fencing, split brain condition, so the following is more of an explanation. Here we go. -------- Cluster, HA, failover, switchover, scalability -------- An attempted definition of a Cluster: A cluster is a set (2+) server nodes dedicated to keep application services alive, communicating through the cluster software/framework with eachother, test and probe health status of servernodes/services and with quorum based decisions and with switchover/failover techniques keep the application services running on them available. That is, should a node that runs a service unexpectedly lose functionality/connection, the other ones would take over the and run the services, so that availability is guaranteed. To provide availability while strictly sticking to a consistent clusterconfiguration is the main goal of a cluster.  At this point we have to add that this defines a HA-cluster, a High-Availability cluster, where the clusternodes are planned to run the services in an active-standby, or failover fashion. An example could be a single instance database. Some applications can be run in a distributed or scalable fashion. In the latter case instances of the application run actively on separate clusternodes serving servicerequests simultaneously. An example for this version could be a webserver that forwards connection requests to many backend servers in a round-robin way. Or a database running in active-active RAC setup.  -------- Cluster arhitecture, interconnect, topologies -------- Now, what is a cluster made of? Servers, right. These servers (the clusternodes) need to communicate. This of course happens over the network, usually over dedicated network interfaces interconnecting all the clusternodes. These connection are called interconnects.How many clusternodes are in a cluster? There are different cluster topologies. The most simple one is a clustered pair topology, involving only two clusternodes:  There are several more topologies, clicking the image above will take you to the relevant documentation. Also, to answer the question Solaris Cluster allows you to run up to 16 servers in a cluster. Where shall these clusternodes be placed? A very important question. The right answer is: It depends on what you plan to achieve with the cluster. Do you plan to avoid only a server outage? Then you can place them right next to eachother in the datacenter. Do you need to avoid DataCenter outage? In that case of course you should place them at least in different fire zones. Or in two geographically distant DataCenters to avoid disasters like floods, large-scale fires or power outages. We call this a stretched- or campus cluster, the clusternodes being several kilometers away from eachother. To cover really large distances, you probably need to move to a GeoCluster, which is a different kind of animal.  What is a geocluster? A Geographic Cluster in Solaris Cluster terms is actually a metacluster between two, separate (locally-HA) clusters.  -------- Cluster resource types, agents, resources, resource groups -------- So how does the cluster manage my applications? The cluster needs to start, stop and probe your applications. If you application runs, the cluster needs to check regularly if the application state is healthy, does it respond over the network, does it have all the processes running, etc. This is called probing. If the cluster deems the application is in a faulty state, then it can try to restart it locally or decide to switch (stop on node A, start on node B) the service. Starting, stopping and probing are the three actions that a cluster agent does. There are many different kinds of agents included in Solaris Cluster, but you can build your own too. Examples are an agent that manages (mounts, moves) ZFS filesystems, or the Oracle DB HA agent that cares about the database, or an agent that moves a floating IP address between nodes. There are lots of other agents included for Apache, Tomcat, MySQL, Oracle DB, Oracle Weblogic, Zones, LDoms, NFS, DNS, etc.We also need to clarify the difference between a cluster resource and the cluster resource group.A cluster resource is something that is managed by a cluster agent. Cluster resource types are included in Solaris cluster (see above, e.g. HAStoragePlus, HA-Oracle, LogicalHost). You can group cluster resources into cluster resourcegroups, and switch these groups together from one node to another. To stick to the example above, to move an Oracle DB service from one node to another, you have to switch the group between nodes, and the agents of the cluster resources in the group will do the following:  On node A Shut down the DB Unconfigure the LogicalHost IP the DB Listener listens on unmount the filesystem   Then, on node B: mount the FS configure the IP  startup the DB -------- Voting, Quorum, Split Brain Condition, Fencing, Amnesia -------- How do the clusternodes agree upon their action? How do they decide which node runs what services? Another important question. Running a cluster is a strictly democratic thing.Every node has votes, and you need the majority of votes to have the deciding power. Now, this is usually no problem, clusternodes think very much all alike. Still, every action needs to be governed upon in a productive system, and has to be agreed upon. Agreeing is easy as long as the clusternodes all behave and talk to eachother over the interconnect. But if the interconnect is gone/down, this all gets tricky and confusing. Clusternodes think like this: "My job is to run these services. The other node does not answer my interconnect communication, it must be down. I'd better take control and run the services!". The problem is, as I have already mentioned, clusternodes very much think alike. If the interconnect is gone, they all assume the other node is down, and they all want to mount the data backend, enable the IP and run the database. Double IPs, double mounts, double DB instances - now that is trouble. Also, in a 2-node cluster they both have only 50% of the votes, that is, they themselves alone are not allowed to run a cluster.  This is where you need a quorum device. According to Wikipedia, the "requirement for a quorum is protection against totally unrepresentative action in the name of the body by an unduly small number of persons.". They need additional votes to run the cluster. For this requirement a 2-node cluster needs a quorum device or a quorum server. If the interconnect is gone, (this is what we call a split brain condition) both nodes start to race and try to reserve the quorum device to themselves. They do this, because the quorum device bears an additional vote, that could ensure majority (50% +1). The one that manages to lock the quorum device (e.g. if it's an FC LUN, it SCSI reserves it) wins the right to build/run a cluster, the other one - realizing he was late - panics/reboots to ensure the cluster config stays consistent.  Losing the interconnect isn't only endangering the availability of services, but it also endangers the cluster configuration consistence. Just imagine node A being down and during that the cluster configuration changes. Now node B goes down, and node A comes up. It isn't uptodate about the cluster configuration's changes so it will refuse to start a cluster, since that would lead to cluster amnesia, that is the cluster had some changes, but now runs with an older cluster configuration repository state, that is it's like it forgot about the changes.  Also, to ensure application data consistence, the clusternode that wins the race makes sure that a server that isn't part of or can't currently join the cluster can access the devices. This procedure is called fencing. This usually happens to storage LUNs via SCSI reservation.  Now, another important question: Where do I place the quorum disk?  Imagine having two sites, two separate datacenters, one in the north of the city and the other one in the south part of it. You run a stretched cluster in the clustered pair topology. Where do you place the quorum disk/server? If you put it into the north DC, and that gets hit by a meteor, you lose one clusternode, which isn't a problem, but you also lose your quorum, and the south clusternode can't keep the cluster running lacking the votes. This problem can't be solved with two sites and a campus cluster. You will need a third site to either place the quorum server to, or a third clusternode. Otherwise, lacking majority, if you lose the site that had your quorum, you lose the cluster. Okay, we covered the very basics. We haven't talked about virtualization support, CCR, ClusterFilesystems, DID devices, affinities, storage-replication, management tools, upgrade procedures - should those be interesting for you, let me know in the comments, along with any other questions. Given enough demand I'd be glad to write a followup post too. Now I really want to move on to the second part in the series: ClusterInstallation.  Oh, as for additional source of information, I recommend the documentation: http://docs.oracle.com/cd/E23623_01/index.html, and the OTN Oracle Solaris Cluster site: http://www.oracle.com/technetwork/server-storage/solaris-cluster/index.html

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  • VLOOKUP in Excel, part 2: Using VLOOKUP without a database

    - by Mark Virtue
    In a recent article, we introduced the Excel function called VLOOKUP and explained how it could be used to retrieve information from a database into a cell in a local worksheet.  In that article we mentioned that there were two uses for VLOOKUP, and only one of them dealt with querying databases.  In this article, the second and final in the VLOOKUP series, we examine this other, lesser known use for the VLOOKUP function. If you haven’t already done so, please read the first VLOOKUP article – this article will assume that many of the concepts explained in that article are already known to the reader. When working with databases, VLOOKUP is passed a “unique identifier” that serves to identify which data record we wish to find in the database (e.g. a product code or customer ID).  This unique identifier must exist in the database, otherwise VLOOKUP returns us an error.  In this article, we will examine a way of using VLOOKUP where the identifier doesn’t need to exist in the database at all.  It’s almost as if VLOOKUP can adopt a “near enough is good enough” approach to returning the data we’re looking for.  In certain circumstances, this is exactly what we need. We will illustrate this article with a real-world example – that of calculating the commissions that are generated on a set of sales figures.  We will start with a very simple scenario, and then progressively make it more complex, until the only rational solution to the problem is to use VLOOKUP.  The initial scenario in our fictitious company works like this:  If a salesperson creates more than $30,000 worth of sales in a given year, the commission they earn on those sales is 30%.  Otherwise their commission is only 20%.  So far this is a pretty simple worksheet: To use this worksheet, the salesperson enters their sales figures in cell B1, and the formula in cell B2 calculates the correct commission rate they are entitled to receive, which is used in cell B3 to calculate the total commission that the salesperson is owed (which is a simple multiplication of B1 and B2). The cell B2 contains the only interesting part of this worksheet – the formula for deciding which commission rate to use: the one below the threshold of $30,000, or the one above the threshold.  This formula makes use of the Excel function called IF.  For those readers that are not familiar with IF, it works like this: IF(condition,value if true,value if false) Where the condition is an expression that evaluates to either true or false.  In the example above, the condition is the expression B1<B5, which can be read as “Is B1 less than B5?”, or, put another way, “Are the total sales less than the threshold”.  If the answer to this question is “yes” (true), then we use the value if true parameter of the function, namely B6 in this case – the commission rate if the sales total was below the threshold.  If the answer to the question is “no” (false), then we use the value if false parameter of the function, namely B7 in this case – the commission rate if the sales total was above the threshold. As you can see, using a sales total of $20,000 gives us a commission rate of 20% in cell B2.  If we enter a value of $40,000, we get a different commission rate: So our spreadsheet is working. Let’s make it more complex.  Let’s introduce a second threshold:  If the salesperson earns more than $40,000, then their commission rate increases to 40%: Easy enough to understand in the real world, but in cell B2 our formula is getting more complex.  If you look closely at the formula, you’ll see that the third parameter of the original IF function (the value if false) is now an entire IF function in its own right.  This is called a nested function (a function within a function).  It’s perfectly valid in Excel (it even works!), but it’s harder to read and understand. We’re not going to go into the nuts and bolts of how and why this works, nor will we examine the nuances of nested functions.  This is a tutorial on VLOOKUP, not on Excel in general. Anyway, it gets worse!  What about when we decide that if they earn more than $50,000 then they’re entitled to 50% commission, and if they earn more than $60,000 then they’re entitled to 60% commission? Now the formula in cell B2, while correct, has become virtually unreadable.  No-one should have to write formulae where the functions are nested four levels deep!  Surely there must be a simpler way? There certainly is.  VLOOKUP to the rescue! Let’s redesign the worksheet a bit.  We’ll keep all the same figures, but organize it in a new way, a more tabular way: Take a moment and verify for yourself that the new Rate Table works exactly the same as the series of thresholds above. Conceptually, what we’re about to do is use VLOOKUP to look up the salesperson’s sales total (from B1) in the rate table and return to us the corresponding commission rate.  Note that the salesperson may have indeed created sales that are not one of the five values in the rate table ($0, $30,000, $40,000, $50,000 or $60,000).  They may have created sales of $34,988.  It’s important to note that $34,988 does not appear in the rate table.  Let’s see if VLOOKUP can solve our problem anyway… We select cell B2 (the location we want to put our formula), and then insert the VLOOKUP function from the Formulas tab: The Function Arguments box for VLOOKUP appears.  We fill in the arguments (parameters) one by one, starting with the Lookup_value, which is, in this case, the sales total from cell B1.  We place the cursor in the Lookup_value field and then click once on cell B1: Next we need to specify to VLOOKUP what table to lookup this data in.  In this example, it’s the rate table, of course.  We place the cursor in the Table_array field, and then highlight the entire rate table – excluding the headings: Next we must specify which column in the table contains the information we want our formula to return to us.  In this case we want the commission rate, which is found in the second column in the table, so we therefore enter a 2 into the Col_index_num field: Finally we enter a value in the Range_lookup field. Important:  It is the use of this field that differentiates the two ways of using VLOOKUP.  To use VLOOKUP with a database, this final parameter, Range_lookup, must always be set to FALSE, but with this other use of VLOOKUP, we must either leave it blank or enter a value of TRUE.  When using VLOOKUP, it is vital that you make the correct choice for this final parameter. To be explicit, we will enter a value of true in the Range_lookup field.  It would also be fine to leave it blank, as this is the default value: We have completed all the parameters.  We now click the OK button, and Excel builds our VLOOKUP formula for us: If we experiment with a few different sales total amounts, we can satisfy ourselves that the formula is working. Conclusion In the “database” version of VLOOKUP, where the Range_lookup parameter is FALSE, the value passed in the first parameter (Lookup_value) must be present in the database.  In other words, we’re looking for an exact match. But in this other use of VLOOKUP, we are not necessarily looking for an exact match.  In this case, “near enough is good enough”.  But what do we mean by “near enough”?  Let’s use an example:  When searching for a commission rate on a sales total of $34,988, our VLOOKUP formula will return us a value of 30%, which is the correct answer.  Why did it choose the row in the table containing 30% ?  What, in fact, does “near enough” mean in this case?  Let’s be precise: When Range_lookup is set to TRUE (or omitted), VLOOKUP will look in column 1 and match the highest value that is not greater than the Lookup_value parameter. It’s also important to note that for this system to work, the table must be sorted in ascending order on column 1! If you would like to practice with VLOOKUP, the sample file illustrated in this article can be downloaded from here. Similar Articles Productive Geek Tips Using VLOOKUP in ExcelImport Microsoft Access Data Into ExcelImport an Access Database into ExcelCopy a Group of Cells in Excel 2007 to the Clipboard as an ImageShare Access Data with Excel in Office 2010 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Quickly Schedule Meetings With NeedtoMeet Share Flickr Photos On Facebook Automatically Are You Blocked On Gtalk? Find out Discover Latest Android Apps On AppBrain The Ultimate Guide For YouTube Lovers Will it Blend? iPad Edition

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  • A dacpac limitation – Deploy dacpac wizard does not understand SqlCmd variables

    - by jamiet
    Since the release of SQL Server 2012 I have become a big fan of using dacpacs for deploying SQL Server databases (for reasons that I will explain some other day) and I chose to use a dacpac to distribute my recently announced utility sp_ssiscatalog (read: Introducing sp_ssiscatalog (v1.0.0.0)). Unfortunately if you read that blog post you may have taken note of the following: Ordinarily a dacpac can be deployed to a SQL Server from SSMS using the Deploy Dacpac wizard however in this case there is a limitation. Due to sp_ssiscatalog referring to objects in the SSIS Catalog (which it has to do of course) the dacpac contains a SqlCmd variable to store the name of the database that underpins the SSIS Catalog; unfortunately the Deploy Dacpac wizard in SSMS has a rather gaping limitation in that it cannot deploy dacpacs containing SqlCmd variables. I think it is worth calling out this limitation separately in this blog post because its a limitation that all dacpac users need to be aware of. If you try and deploy the dacpac containing sp_ssiscatalog using the wizard in SSMS then this is what you will see: TITLE: Microsoft SQL Server Management Studio ------------------------------ Could not deploy package. (Microsoft.SqlServer.Dac) ------------------------------ ADDITIONAL INFORMATION: Missing values for the following SqlCmd variables:SSISDB. (Microsoft.Data.Tools.Schema.Sql) ------------------------------ BUTTONS: OK ------------------------------ The message is quite correct. The SSDT DB project that I used to build this dacpac *does* have a SqlCmd variable in it called SSISDB: Quite simply, the Dac Deployment wizard in SSMS is not capable of deploying such dacpacs. Your only option for deploying such dacpacs is to use the command-line tool sqlpackage.exe. Generally I use sqlpackage.exe anyway (which is why it has taken me months to encounter the aforementioned problem) and have found it preferable to using a GUI-based wizard. Your mileage may vary. @Jamiet

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  • How to write PowerShell code part 1 (Using external xml configuration file)

    - by ybbest
    In this post, I will show you how to use external xml file with PowerShell. The advantage for doing so is that you can avoid other people to open up your PowerShell code to make the configuration changes; instead all they need to do is to change the xml file. I will refactor my site creation script as an example; you can download the script here and refactored code here. 1. As you can see below, I hard code all the variables in the script itself. $url = "http://ybbest" $WebsiteName = "Ybbest" $WebsiteDesc = "Ybbest test site" $Template = "STS#0" $PrimaryLogin = "contoso\administrator" $PrimaryDisplay = "administrator" $PrimaryEmail = "[email protected]" $MembersGroup = "$WebsiteName Members" $ViewersGroup = "$WebsiteName Viewers" 2. Next, I will show you how to manipulate xml file using PowerShell. You can use the get-content to grab the content of the file. [xml] $xmlconfigurations=get-content .\SiteCollection.xml 3. Then you can set it to variable (the variable has to be typed [xml] after that you can read the content of the xml content, PowerShell also give you nice IntelliSense by press the Tab key. [xml] $xmlconfigurations=get-content .\SiteCollection.xml $xmlconfigurations.SiteCollection $xmlconfigurations.SiteCollection.SiteName 4. After refactoring my code, I can set the variables using the xml file as below. #Set the parameters $siteInformation=$xmlinput.SiteCollection $url = $siteInformation.URL $siteName = $siteInformation.SiteName $siteDesc = $siteInformation.SiteDescription $Template = $siteInformation.SiteTemplate $PrimaryLogin = $siteInformation.PrimaryLogin $PrimaryDisplay = $siteInformation.PrimaryDisplayName $PrimaryEmail = $siteInformation.PrimaryLoginEmail $MembersGroup = "$WebsiteName Members" $ViewersGroup = "$WebsiteName Viewers"

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  • Operator of the week - Assert

    - by Fabiano Amorim
    Well my friends, I was wondering how to help you in a practical way to understand execution plans. So I think I'll talk about the Showplan Operators. Showplan Operators are used by the Query Optimizer (QO) to build the query plan in order to perform a specified operation. A query plan will consist of many physical operators. The Query Optimizer uses a simple language that represents each physical operation by an operator, and each operator is represented in the graphical execution plan by an icon. I'll try to talk about one operator every week, but so as to avoid having to continue to write about these operators for years, I'll mention only of those that are more common: The first being the Assert. The Assert is used to verify a certain condition, it validates a Constraint on every row to ensure that the condition was met. If, for example, our DDL includes a check constraint which specifies only two valid values for a column, the Assert will, for every row, validate the value passed to the column to ensure that input is consistent with the check constraint. Assert  and Check Constraints: Let's see where the SQL Server uses that information in practice. Take the following T-SQL: IF OBJECT_ID('Tab1') IS NOT NULL   DROP TABLE Tab1 GO CREATE TABLE Tab1(ID Integer, Gender CHAR(1))  GO  ALTER TABLE TAB1 ADD CONSTRAINT ck_Gender_M_F CHECK(Gender IN('M','F'))  GO INSERT INTO Tab1(ID, Gender) VALUES(1,'X') GO To the command above the SQL Server has generated the following execution plan: As we can see, the execution plan uses the Assert operator to check that the inserted value doesn't violate the Check Constraint. In this specific case, the Assert applies the rule, 'if the value is different to "F" and different to "M" than return 0 otherwise returns NULL'. The Assert operator is programmed to show an error if the returned value is not NULL; in other words, the returned value is not a "M" or "F". Assert checking Foreign Keys Now let's take a look at an example where the Assert is used to validate a foreign key constraint. Suppose we have this  query: ALTER TABLE Tab1 ADD ID_Genders INT GO  IF OBJECT_ID('Tab2') IS NOT NULL   DROP TABLE Tab2 GO CREATE TABLE Tab2(ID Integer PRIMARY KEY, Gender CHAR(1))  GO  INSERT INTO Tab2(ID, Gender) VALUES(1, 'F') INSERT INTO Tab2(ID, Gender) VALUES(2, 'M') INSERT INTO Tab2(ID, Gender) VALUES(3, 'N') GO  ALTER TABLE Tab1 ADD CONSTRAINT fk_Tab2 FOREIGN KEY (ID_Genders) REFERENCES Tab2(ID) GO  INSERT INTO Tab1(ID, ID_Genders, Gender) VALUES(1, 4, 'X') Let's look at the text execution plan to see what these Assert operators were doing. To see the text execution plan just execute SET SHOWPLAN_TEXT ON before run the insert command. |--Assert(WHERE:(CASE WHEN NOT [Pass1008] AND [Expr1007] IS NULL THEN (0) ELSE NULL END))      |--Nested Loops(Left Semi Join, PASSTHRU:([Tab1].[ID_Genders] IS NULL), OUTER REFERENCES:([Tab1].[ID_Genders]), DEFINE:([Expr1007] = [PROBE VALUE]))           |--Assert(WHERE:(CASE WHEN [Tab1].[Gender]<>'F' AND [Tab1].[Gender]<>'M' THEN (0) ELSE NULL END))           |    |--Clustered Index Insert(OBJECT:([Tab1].[PK]), SET:([Tab1].[ID] = RaiseIfNullInsert([@1]),[Tab1].[ID_Genders] = [@2],[Tab1].[Gender] = [Expr1003]), DEFINE:([Expr1003]=CONVERT_IMPLICIT(char(1),[@3],0)))           |--Clustered Index Seek(OBJECT:([Tab2].[PK]), SEEK:([Tab2].[ID]=[Tab1].[ID_Genders]) ORDERED FORWARD) Here we can see the Assert operator twice, first (looking down to up in the text plan and the right to left in the graphical plan) validating the Check Constraint. The same concept showed above is used, if the exit value is "0" than keep running the query, but if NULL is returned shows an exception. The second Assert is validating the result of the Tab1 and Tab2 join. It is interesting to see the "[Expr1007] IS NULL". To understand that you need to know what this Expr1007 is, look at the Probe Value (green text) in the text plan and you will see that it is the result of the join. If the value passed to the INSERT at the column ID_Gender exists in the table Tab2, then that probe will return the join value; otherwise it will return NULL. So the Assert is checking the value of the search at the Tab2; if the value that is passed to the INSERT is not found  then Assert will show one exception. If the value passed to the column ID_Genders is NULL than the SQL can't show a exception, in that case it returns "0" and keeps running the query. If you run the INSERT above, the SQL will show an exception because of the "X" value, but if you change the "X" to "F" and run again, it will show an exception because of the value "4". If you change the value "4" to NULL, 1, 2 or 3 the insert will be executed without any error. Assert checking a SubQuery: The Assert operator is also used to check one subquery. As we know, one scalar subquery can't validly return more than one value: Sometimes, however, a  mistake happens, and a subquery attempts to return more than one value . Here the Assert comes into play by validating the condition that a scalar subquery returns just one value. Take the following query: INSERT INTO Tab1(ID_TipoSexo, Sexo) VALUES((SELECT ID_TipoSexo FROM Tab1), 'F')    INSERT INTO Tab1(ID_TipoSexo, Sexo) VALUES((SELECT ID_TipoSexo FROM Tab1), 'F')    |--Assert(WHERE:(CASE WHEN NOT [Pass1016] AND [Expr1015] IS NULL THEN (0) ELSE NULL END))        |--Nested Loops(Left Semi Join, PASSTHRU:([tempdb].[dbo].[Tab1].[ID_TipoSexo] IS NULL), OUTER REFERENCES:([tempdb].[dbo].[Tab1].[ID_TipoSexo]), DEFINE:([Expr1015] = [PROBE VALUE]))              |--Assert(WHERE:([Expr1017]))             |    |--Compute Scalar(DEFINE:([Expr1017]=CASE WHEN [tempdb].[dbo].[Tab1].[Sexo]<>'F' AND [tempdb].[dbo].[Tab1].[Sexo]<>'M' THEN (0) ELSE NULL END))              |         |--Clustered Index Insert(OBJECT:([tempdb].[dbo].[Tab1].[PK__Tab1__3214EC277097A3C8]), SET:([tempdb].[dbo].[Tab1].[ID_TipoSexo] = [Expr1008],[tempdb].[dbo].[Tab1].[Sexo] = [Expr1009],[tempdb].[dbo].[Tab1].[ID] = [Expr1003]))              |              |--Top(TOP EXPRESSION:((1)))              |                   |--Compute Scalar(DEFINE:([Expr1008]=[Expr1014], [Expr1009]='F'))              |                        |--Nested Loops(Left Outer Join)              |                             |--Compute Scalar(DEFINE:([Expr1003]=getidentity((1856985942),(2),NULL)))              |                             |    |--Constant Scan              |                             |--Assert(WHERE:(CASE WHEN [Expr1013]>(1) THEN (0) ELSE NULL END))              |                                  |--Stream Aggregate(DEFINE:([Expr1013]=Count(*), [Expr1014]=ANY([tempdb].[dbo].[Tab1].[ID_TipoSexo])))             |                                       |--Clustered Index Scan(OBJECT:([tempdb].[dbo].[Tab1].[PK__Tab1__3214EC277097A3C8]))              |--Clustered Index Seek(OBJECT:([tempdb].[dbo].[Tab2].[PK__Tab2__3214EC27755C58E5]), SEEK:([tempdb].[dbo].[Tab2].[ID]=[tempdb].[dbo].[Tab1].[ID_TipoSexo]) ORDERED FORWARD)  You can see from this text showplan that SQL Server as generated a Stream Aggregate to count how many rows the SubQuery will return, This value is then passed to the Assert which then does its job by checking its validity. Is very interesting to see that  the Query Optimizer is smart enough be able to avoid using assert operators when they are not necessary. For instance: INSERT INTO Tab1(ID_TipoSexo, Sexo) VALUES((SELECT ID_TipoSexo FROM Tab1 WHERE ID = 1), 'F') INSERT INTO Tab1(ID_TipoSexo, Sexo) VALUES((SELECT TOP 1 ID_TipoSexo FROM Tab1), 'F')  For both these INSERTs, the Query Optimiser is smart enough to know that only one row will ever be returned, so there is no need to use the Assert. Well, that's all folks, I see you next week with more "Operators". Cheers, Fabiano

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  • Why does display:table-cell not center content without display:table?

    - by Samuel
    I'm looking for the most efficient (or elegant) way to vertically and horizontally center content of variable height. I've come up with this: http://cssdeck.com/t/2veysdkg/16, which uses css tables to vertically center the main content. My demands for writing this particular piece of code were: Must be able to center variable and fixed width content vertically and horizontally Centered content must be inside the normal document flow (so no overlapping) Sticky footer and normal header of 100% width As few hacks, ugly code or non-semantic html as possible I didn't care about support for IE6, IE7 (I'll use a different stylesheet for them) The weird thing is that the demands above are only met when the header and footer are set to table-row, and the body-tag to display:table. Which is weird because as I understand it the css will generate anonymous table elements when parent table elements are missing. So table-cell should work without all the surrounding elements, but yet I've not been able to make it work. If it were up to me I would prefer to not mess with the display mode for the body tag, and leave the header and footer on display:block. But I've not been able to make it work. Does anyone understand why this doesn't work?

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  • SQL SERVER – Table Variables and Transactions – SQL in Sixty Seconds #007 – Video

    - by pinaldave
    Today’s SQL in Sixty Seconds video is inspired from my presentation at TechEd India 2012 on Misconception and Resolution. Quite often I have seen people getting confused with certain behavior of the T-SQL. They expect SQL to behave certain way and SQL Server behave differently. This kind of issue often creates confusion and frustration. Sometime I have seen them also confusing it with bug and submitting the bug, where reality is totally different. Similar concept which are going to see today. I have seen quite commonly developer assuming that table various will be rolled back when transaction is rolled back. This sixty seconds video describes that table various are not rolled back when transactions are rolled back. More on Errors: Difference Temp Table and Table Variable – Effect of Transaction Effect of TRANSACTION on Local Variable – After ROLLBACK and After COMMIT Debate – Table Variables vs Temporary Tables – Quiz – Puzzle – 13 of 31 I encourage you to submit your ideas for SQL in Sixty Seconds. We will try to accommodate as many as we can. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL in Sixty Seconds, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Video

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  • emca fails with "Database instance is unavailable" though available

    - by Giri Mandalika
    The following example shows the symptoms of failure, and the exact error message. $ emca -repos create ... Password for SYSMAN user: Do you wish to continue? [yes(Y)/no(N)]: Y Nov 19, 2012 10:33:42 AM oracle.sysman.emcp.DatabaseChecks \ checkDbAvailabilityImpl WARNING: ORA-01034: ORACLE not available Nov 19, 2012 10:33:42 AM oracle.sysman.emcp.DatabaseChecks \ throwDBUnavailableException SEVERE: Database instance is unavailable. Fix the ORA error thrown and run EM Configuration Assistant again. Some of the possible reasons may be : 1) Database may not be up. 2) Database is started setting environment variable ORACLE_HOME with trailing '/'. Reset ORACLE_HOME and bounce the database. For eg. Database is started setting environment variable ORACLE_HOME=/scratch/db/ . Reset ORACLE_HOME=/scratch/db and bounce the database. Fix: Ensure that the ORACLE_HOME is pointing to the right location in $ORACLE_HOME/bin/emca file. Rather than installing from scratch, if ORACLE_HOME was copied over from another location, likely it results in wrong location for ORACLE_HOME in several Enterprise Manager (EM) specific scripts and files. It usually happens when the directory structure on the target machine is not identical to the structure on the original/source machine, including the top level directory location where Oracle RDBMS was installed properly using the installer.

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  • Database Web Service using Toplink DB Provider

    - by Vishal Jain
    With JDeveloper 11gR2 you can now create database based web services using JAX-WS Provider. The key differences between this and the already existing PL/SQL Web Services support is:Based on JAX-WS ProviderSupports SQL Queries for creating Web ServicesSupports Table CRUD OperationsThis is present as a new option in the New Gallery under 'Web Services'When you invoke the New Gallery option, it present you with three options to choose from:In this entry I will explain the options of creating service based on SQL queries and Table CRUD operations.SQL Query based Service When you select this option, on 'Next' page it asks you for the DB Conn details. You can also choose if you want SOAP 1.1 or 1.2 format. For this example, I will proceed with SOAP 1.1, the default option.On the Next page, you can give the SQL query. The wizard support Bind Variables, so you can parametrize your queries. Give "?" as a input parameter you want to give at runtime, and the "Bind Variables" button will get enabled. Here you can specify the name and type of the variable.Finish the wizard. Now you can test your service in Analyzer:See that the bind variable specified comes as a input parameter in the Analyzer Input Form:CRUD OperationsFor this, At Step 2 of Wizard, select the radio button "Generate Table CRUD Service Provider"At the next step, select the DB Connection and the table for which you want to generate the default set of operations:Finish the Wizard. Now, run the service in Analyzer for a quick check.See that all the basic operations are exposed:

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  • Is there any functional difference between immutable value types and immutable reference types?

    - by Kendall Frey
    Value types are types which do not have an identity. When one variable is modified, other instances are not. Using Javascript syntax as an example, here is how a value type works. var foo = { a: 42 }; var bar = foo; bar.a = 0; // foo.a is still 42 Reference types are types which do have an identity. When one variable is modified, other instances are as well. Here is how a reference type works. var foo = { a: 42 }; var bar = foo; bar.a = 0; // foo.a is now 0 Note how the example uses mutatable objects to show the difference. If the objects were immutable, you couldn't do that, so that kind of testing for value/reference types doesn't work. Is there any functional difference between immutable value types and immutable reference types? Is there any algorithm that can tell the difference between a reference type and a value type if they are immutable? Reflection is cheating. I'm wondering this mostly out of curiosity.

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  • Am I wrong to disagree with A Gentle Introduction to symfony's template best practices?

    - by AndrewKS
    I am currently learning symfony and going through the book A Gentle Introduction to symfony and came across this section in "Chapter 4: The Basics of Page Creation" on creating templates (or views): "If you need to execute some PHP code in the template, you should avoid using the usual PHP syntax, as shown in Listing 4-4. Instead, write your templates using the PHP alternative syntax, as shown in Listing 4-5, to keep the code understandable for non-PHP programmers." Listing 4-4 - The Usual PHP Syntax, Good for Actions, But Bad for Templates <p>Hello, world!</p> <?php if ($test) { echo "<p>".time()."</p>"; } ?> (The ironic thing about this is that echo statement would look even better if time was variable declared in the controller, because then you could just embed the variable in the string instead of concatenating) Listing 4-5 - The Alternative PHP Syntax, Good for Templates <p>Hello, world!</p> <?php if ($test): ?> <p><?php echo time(); ?> </p><?php endif; ?> I fail to see how listing 4-5 makes the code "understandable for non-PHP programmers", and its readability is shaky at best. 4-4 looks much more readable to me. Are there any programmers who are using symfony that write their templates like those in 4-4 rather than 4-5? Are there reasons I should use one over the other? There is the very slim chance that somewhere down the road someone less technical could be editing it the template, but how does 4-5 actually make it more understandable to them?

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  • Keeping multiple root directories in a single partition

    - by intuited
    I'm working out a partition scheme for a new install. I'd like to keep the root filesystem fairly small and static, so that I can use LVM snapshots to do backups without having to allocate a ton of space for the snapshot. However, I'd also like to keep the number of total partitions small. Even with LVM, there's inevitably some wasted space and it's still annoying and vaguely dangerous to allocate more. So there seem to be a couple of different options: Have the partition that will contain bulky, variable files, like /srv, /var, and /home, be the root partition, and arrange for the core system state — /etc, /usr, /lib, etc. — to live in a second partition. These files can (I think) be backed up using a different backup scheme, and I don't think LVM snapshots will be necessary for them. The opposite: putting the big variable directories on the second partition, and having the essential system directories live on the root FS. Either of these options require that certain directories be pointers of some variety to subdirectories of a second partition. I'm aware of two different ways to do this: symlinks and bind-mounts. Is one better than the other for this purpose? Is there another option? Do any of the various Ubuntu installation media/strategies support this style of partition layout?

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  • extra configuration needed after installing SSL certificate?

    - by ptriek
    We recently developed two rather simple PHP applications for AXA (European bank). URL's are axa.tfo.be/incentives/cipres and axa.tfo.be/incentives/zrkk (access to both sites is restricted to visitors with cookies with encrypted passwords) On a previous security audit by an external company several security issues have been found. All these issues have been solved by a collleague PHP developer. However, one last requirement has been added - all data should be transfered over https. My php collegue is on holiday, however - and unavailable at the moment. So I contacted my host, and asked for installing SSL certificate. I myself have no knowledge/experience with SSL, so I'm a bit at loss for the following problems. Comodo SSL certificate + unique IP address has been installed today by my webhost for subdomain axa.tfo.be (by www.combell.be). However, it doesn't seem to be working. I posted a question about this earlier today, and was told not to worry, see link: http://serverfault.com/questions/339320/what-happens-if-you-install-an-ssl-certificate Current problems: the web applications aren't accessible over https, http works though (if a valid cookie is available) there's a static html page at http://axa.tfo.be/incentives/cipres/static.html, even that page is only accessible over http My webhost is telling me that 'my application probably doesn't support SSL', and has asked me to set an SSL variable to true in my php code. So my questions: I have basic knowledge of php, but don't know where to start regarding the 'php ssl variable'. The sites have been online for some time, and have been developed for regular php access. (Google didn't bring me any help, either.) Can anyone point me in the right direction, or give me some clues about whether/what I should ask my webhost for further assistance? (I'm a bit on a tight schedule, the sites will be audited again on monday, and it's a customer i wouldn't want to loose...) Thanks for looking into this, and sorry if my questions sound a bit nooby - I'm a webdesigner, not a server specialist...

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  • How to implement a stack of game states in C++

    - by Lisandro Vaccaro
    I'm new to C++ and as a college proyect I'm building a 2D platformer with some classmates, I recently read that it's a good idea to have a stack of gamestates instead of a single global variable with the game state (which is what I have now) but I'm not sure how to do it. Currently this is my implementation: class GameState { public: virtual ~GameState(){}; virtual void handle_events() = 0; virtual void logic() = 0; virtual void render() = 0; }; class Menu : public GameState { public: Menu(); ~Menu(); void handle_events(); void logic(); void render(); }; Then I have a global variable of type GameState: GameState *currentState = NULL; And in my Main I define the currentState and call it's methods: int main(){ currentState = new Menu(); currentState.handle_events(); } How can I implement a stack or something similar to go from that to something like this: int main(){ statesStack.push(new Menu()); statesStack.getTop().handle_events(); }

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  • .htaccess URL rewriting friendly URL with 2 parameters, the second parameter is optional

    - by letsworktogether
    I'm kind of stuck at this part and was hoping that I'd get some assistance. I'm building a highscores page in PHP, that's going great, it works. However, I dislike the idea of index.php?skill=name and therefore wanted a bit of SEO in this. I have successfully replaced the url with a more friendly version: highscores/skill/name And this is where the problem starts, I have added pagination to the highscores and the page is read from the HTTP_GET page variable ($_GET['page']). I dislike the idea of highscores/skill/name&page=2 and was hoping if you guys could assist me to make the url like the following: Page 1, so accessing the file without declaring the page number: DOMAIN.TLD/highscores/skill/name Page 1 so now the page variable is needed: DOMAIN.TLD/highscores/skill/name/2 As you can tell the "2" will define page 2 and load the correct data for page 2. However, I'm having much trouble in my .htaccess file to configure it this way. RewriteRule ^highscores\/skill\/(.*?)(\/(.*?)*)$ highscores/skills.php?skill=$1&page=$2 [L] # Skills page That is my latest attempt in order to get it to work, unfortunately it does not work, it makes the page look horrible (CSS doesn't work) and it doesn't go to the page specified on the URL.

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  • Animating Tile with Blitting taking up Memory.

    - by Kid
    I am trying to animate a specific tile in my 2d Array, using blitting. The animation consists of three different 16x16 sprites in a tilesheet. Now that works perfect with the code below. BUT it's causing memory leakage. Every second the FlashPlayer is taking up +140 kb more in memory. What part of the following code could possibly cause the leak: //The variable Rectangle finds where on the 2d array we should clear the pixels //Fillrect follows up by setting alpha 0 at that spot before we copy in nxt Sprite //Tiletype is a variable that holds what kind of tile the next tile in animation is //(from tileSheet) //drawTile() gets Sprite from tilesheet and copyPixels it into right position on canvas public function animateSprite():void{ tileGround.bitmapData.lock(); if(anmArray[0].tileType > 42){ anmArray[0].tileType = 40; frameCount = 0; } var rect:Rectangle = new Rectangle(anmArray[0].xtile * ts, anmArray[0].ytile * ts, ts, ts); tileGround.bitmapData.fillRect(rect, 0); anmArray[0].tileType = 40 + frameCount; drawTile(anmArray[0].tileType, anmArray[0].xtile, anmArray[0].ytile); frameCount++; tileGround.bitmapData.unlock(); } public function drawTile(spriteType:int, xt:int, yt:int):void{ var tileSprite:Bitmap = getImageFromSheet(spriteType, ts); var rec:Rectangle = new Rectangle(0, 0, ts, ts); var pt:Point = new Point(xt * ts, yt * ts); tileGround.bitmapData.copyPixels(tileSprite.bitmapData, rec, pt, null, null, true); } public function getImageFromSheet(spriteType:int, size:int):Bitmap{ var sheetColumns:int = tSheet.width/ts; var col:int = spriteType % sheetColumns; var row:int = Math.floor(spriteType/sheetColumns); var rec:Rectangle = new Rectangle(col * ts, row * ts, size, size); var pt:Point = new Point(0,0); var correctTile:Bitmap = new Bitmap(new BitmapData(size, size, false, 0)); correctTile.bitmapData.copyPixels(tSheet, rec, pt, null, null, true); return correctTile; }

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  • What is the best practice for when to check if something needs to be done?

    - by changokun
    Let's say I have a function that does x. I pass it a variable, and if the variable is not null, it does some action. And I have an array of variables and I'm going to run this function on each one. Inside the function, it seems like a good practice is to check if the argument is null before proceeding. A null argument is not an error, it just causes an early return. I could loop through the array and pass each value to the function, and the function will work great. Is there any value to checking if the var is null and only calling the function if it is not null during the loop? This doubles up on the checking for null, but: Is there any gained value? Is there any gain on not calling a function? Any readability gain on the loop in the parent code? For the sake of my question, let's assume that checking for null will always be the case. I can see how checking for some object property might change over time, which makes the first check a bad idea. Pseudo code example: for(thing in array) { x(thing) } Versus: for(thing in array) { if(thing not null) x(thing) } If there are language-specific concerns, I'm a web developer working in PHP and JavaScript.

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  • Play Updated Retro Arcade Games for Free Courtesy of Microsoft

    - by Jason Fitzpatrick
    As part of a promotion for Internet Explorer 10, Microsoft comissioned Atari to update several classic retro games from the arcade and the Atari consoles. Fortunately for those of us looking for a retro gaming fix, you can play the games in any HTML5-enabled browser. While game play is really smooth on most games there are a few little quirks that using Internet Explorer 10 does take care of. First, if you’re not on IE10, you’ll see a little advertisement before you begin playing each game. Second, some games call on some of the new touch/motion variable functionality built into IE10 for the Windows 8 tablet experience and they’ll stall out when they reach the point in the game they need to call that variable. That said, we played quite a few games without any hiccups at all. Hit up the link below to play classics like Asteroids, Lunar Lander, Pong, Super Breakout, and more. Atari IE10 Promo Gallery [Atari] HTG Explains: Why Do Hard Drives Show the Wrong Capacity in Windows? Java is Insecure and Awful, It’s Time to Disable It, and Here’s How What Are the Windows A: and B: Drives Used For?

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