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  • In SQL Server 2000, how to delete the specified rows in a table that does not have a primary key?

    - by Yousui
    Hi, Let's say we have a table with some data in it. IF OBJECT_ID('dbo.table1') IS NOT NULL BEGIN DROP TABLE dbo.table1; END CREATE TABLE table1 ( DATA INT ); --------------------------------------------------------------------- -- Generating testing data --------------------------------------------------------------------- INSERT INTO dbo.table1(data) SELECT 100 UNION ALL SELECT 200 UNION ALL SELECT NULL UNION ALL SELECT 400 UNION ALL SELECT 400 UNION ALL SELECT 500 UNION ALL SELECT NULL; How to delete the 2nd, 5th, 6th records in the table? The order id defined by the following query. SELECT data FROM dbo.table1 ORDER BY data DESC; Note, this is in SQL Server 2000 environment. Thanks.

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  • how to compress a PNG image using Java

    - by 116213060698242344024
    Hi I would like to know if there is any way in Java to reduce the size of an image (use any kind of compression) that was loaded as a BufferedImage and is going to be saved as an PNG. Maybe some sort of png imagewriteparam? I didnt find anything helpful so im stuck. heres a sample how the image is loaded and saved public static BufferedImage load(String imageUrl) { Image image = new ImageIcon(imageUrl).getImage(); bufferedImage = new BufferedImage(image.getWidth(null), image.getHeight(null), BufferedImage.TYPE_INT_ARGB); Graphics2D g2D = bufferedImage.createGraphics(); g2D.drawImage(image, 0, 0, null); return bufferedImage; } public static void storeImageAsPng(BufferedImage image, String imageUrl) throws IOException { ImageIO.write(image, "png", new File(imageUrl)); }

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  • How to suppress a MongoDDException when proxy can't find a referenced document

    - by Madarco
    We are using Symfony2/DoctrineOdm/MongoDB and when we do: if ($doc.referenceOne != null) { ... } and the $doc.referenceOne contains a MongoDbRef that point to a deleted/lost document, the Doctrine Proxy object raises a MongoDBException. It is possible to tell the Proxy return null instead of raising the exception? Detailed Explanation: Our document: class User { /* @MongoDB\ReferenceOne( ... ) */ private $photo; } If $photo contains a MongoDbRef, but the document is lost/deleted, when we do if ($user.photo) { ... } doctrine will raise a MongoDBException: The "Proxies\DocumentPhotoProxy" document with identifier "4fd8b3ef732bafab7b000000" could not be found We want to suppress the exception since our application can handle null values in that variable. (we could simply log that error, while the exception propagate to a 500 page and disrupt our service)

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  • Is void *p = 0L valid?

    - by Artefacto
    In this answer, sassman initializes a pointer with: zend_class_entry* ce = 0L; My question is – is this valid? I would say it isn't, to initialize the variable with a null pointer either an unadorned (and possibly casted to void *) 0 constant, or some macro that evaluates to that such as NULL should be used. However, I can't find definitive language in the standard that supports this interpretation. All it says is: An integer constant expression with the value 0, or such an expression cast to type void *, is called a null pointer constant.

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  • how i insert values from list of Data Grid View,current time ,EmployeeID using button click event (C

    - by Six fourty
    hi, it show me this error Incorrect syntax near the keyword 'Select' to make to clear Employee ID in this case is FK in the table (Attendance detail) and the other thing is i am using Data Grid View from another table(Employee information) to Show the list of the staff in my form. then i want to transfer each selected cell value from Data Grid View to attendance detail table. 10q private void time_in_Click(object sender, EventArgs e) { employee_InformationDataGridView.SelectedCells[0].Style.ForeColor = Color.Green; time_in.Enabled = false; time_out.Enabled = true; con = new SqlConnection(GlobalClass.conn); con.Open(); SqlCommand cmd = new SqlCommand("Insert into Attendancedetail Values(" + "Select from EmployeeInformation(EmployeeID)" + ",'" + employee_InformationDataGridView.SelectedCells[0] + "','" + DateTime.Now.ToLongDateString() + "','" + null + "','" + null + "','" + DateTime.Now.ToLongTimeString() + "'," + null + ")", con); int i = cmd.ExecuteNonQuery(); MessageBox.Show(i.ToString() + " record inserted"); }

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  • SQL insert default value

    - by Stan
    Say if I have a table like CREATE TABLE [Message] ( [MessageIdx] [int] IDENTITY (1, 1) NOT NULL , [Message] [varchar] (1024) COLLATE Latin1_General_CI_AS NOT NULL , [ValidUntil] [datetime] NULL , CONSTRAINT [PK_Message] PRIMARY KEY CLUSTERED ( [MessageIdx] ) WITH FILLFACTOR = 90 ON [PRIMARY] ) ON [PRIMARY] GO I am trying to insert value without specify column names explicitly. Below statement causes error. How can I do that? Thanks. set identity_insert caconfig..fxmessage on; insert into message values (DEFAULT,'blah',DEFAULT); set identity_insert caconfig..fxmessage off;

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  • Android liveWallpaper background

    - by Beginer Developer
    How do I scroll the background image on an ACTION_MOVE event? Here is my code used to draw the background image: void drawFrame() { final SurfaceHolder holder = getSurfaceHolder(); Canvas c = null; try { c = holder.lockCanvas(); if (c != null) { c.drawBitmap(myBg, 0, 0, mPaint); } } finally { if (c != null) holder.unlockCanvasAndPost(c); } // Reschedule the next redraw mHandler.removeCallbacks(mDrawAnim); if (mVisible && mAnime) { mHandler.postDelayed(mDrawAnim, 50 ); } }

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  • Is this bad coding practice?

    - by user566540
    I'm using PC-lint to analyze my code and theese lines are generating several errors. That makes me wonder if my coding pratice is wrong? char *start; char *end; // Extract the phone number start = (char*) (strchr(data, '\"') +1); end = (char*) strchr(start, '\"'); *end = 0; strlcpy((char*)Fp_smsSender, start , start-(end-1)); EDIT: After your help i now have: char *start; char *end; if (data != NULL) { // Extract the phone number start = strchr(data, '\"'); if (start != NULL) { ++start; end = strchr(start, '\"'); if (end != NULL) { *end = 0; strlcpy((char*)Fp_smsSender, start , FP_MAX_PHONE); } } How does that look?

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  • Understanding memory leak in Android app.

    - by sat
    After going through few articles about performance, Not able to get this statement exactly. "When a Drawable is attached to a view, the view is set as a callback on the drawable" Soln: "Setting the stored drawables’ callbacks to null when the activity is destroyed." What does that mean, e.g. In my app , I initialize an imageButton in onCreate() like this, imgButton= (ImageButton) findViewById(R.id.imagebtn); At later stage, I get an image from an url, get the stream and convert that to drawable, and set image btn like this, imgButton.setImageDrawable(drawable); According to the above statement, when I am exiting my app, say in onDestroy() I have to set stored drawables’ callbacks to null, not able to understand this part ! In this simple case what I have to set as null ? I am using Android 2.2 Froyo, whether this technique is required, or not necessary.

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  • seg violation using pycapsule_new

    - by user1733051
    I am trying some simple c API, where I am using PyCapsule_New to encapsulate a pointer. I am running into segment violation, can some body help me. mystruct *func1(int streamno, char mode,unsigned int options) { char * s; s=malloc(100); return s; } PyObject *Wrapper_func1(PyObject *self, PyObject *args) { int streamno; char mode; unsigned int options; mystruct* result; if (!PyArg_ParseTuple(args,"icI",&streamno,&mode,&options)) return NULL; result = func1(streamno,mode,options); return PyCapsule_New( result,NULL,NULL); }

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  • How to join the results of two tables in django python

    - by user1787524
    I have two models class Weather(model.model): region = models.ForeignKey(Region) district = models.ForeignKey(District) temp_max = models.IntegerField(blank=True, null=True, verbose_name='Max temperature (C)') temp_min = models.IntegerField(blank=True, null=True, verbose_name='Min temperature (C)') and class Plan(model.model): name = tinymce_models.HTMLField(blank=True, null=True) region = models.ForeignKey(Region) district = models.ForeignKey(District) Provided for every region and district have unique row. I want to combine the result so that i can get all the columns of both tables These two Models are not related to each other. ' I need to make the join like join weather w on w.region = A.region and w.distric = A.district so that result contains all the columns in everyobject like obj.temp_max etc

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  • Is there a method I can override on a JavaScript object to control what is displayed by console.log?

    - by agnoster
    I'm thinking in particular of Chrome, though Firebug would be interesting to. I've tried toString() and valueOf(), but neither of those seem to be used. Interestingly, if I take a function it'll display the function definition - but then if I add a toString() method it will show null! var a = function(){}; console.log(a); // output: function (){} a.toString = function(){ return 'a'; }; console.log(a); // output: null a.valueOf = function(){ return 'v'; }; console.log(a); // output: null Any ideas?

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  • How to get the Drive letter and Mount Path - MSDN

    - by new
    Hello all, I get the devices list from the system using SetupDiGetClassDevs Function - MSDN. Also i can able to get the vendor id and product id from the devices. But i cant able to get the drive letter and the mount path For Example if i plug the usb drive means , i have to get the drive letter like "G:/" Please help me to get the drive letter and mount path for the devices if (SetupDiEnumDeviceInterfaces(hDevInfo, NULL,&GUID_DEVINTERFACE_USB_DEVICE,i,&Interface_Info)) { wprintf(L"\tDeviccvcvcveInstanceId : %d\n", i); pspdidd->cbSize = sizeof(*pspdidd); SP_DEVICE_INTERFACE_DETAIL_DATA *pDetData = NULL; DWORD dwDetDataSize = sizeof (SP_DEVICE_INTERFACE_DETAIL_DATA) + 256; pDetData = (SP_DEVICE_INTERFACE_DETAIL_DATA*) malloc (dwDetDataSize); pDetData->cbSize = sizeof (SP_DEVICE_INTERFACE_DETAIL_DATA); SetupDiGetDeviceInterfaceDetail(hDevInfo,&Interface_Info,pDetData,dwDetDataSize, NULL,&DeviceInfoData); qDebug ()<<QString::fromWCharArray( pDetData->DevicePath ); }

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  • Convert JSON data into String

    - by san6086
    Hi I am converting JSON data into String. Please find the JSON data below. I am facing an issue where in the system is unable to convert NULL values into string. Therefore, I am getting the following error: can't convert nil into String (TypeError) JSON DATA: {"success":true,"message":null,"data":null} Code Used: c = Curl::Easy.new(Configuration.fetch("<URL where we can find the above JSON DATA and nothing else>")) # c.follow_location = true # c.http_auth_types = :basic # c.username = Configuration.fetch('auth_user', false) # c.password = Configuration.fetch('auth_pass', false) # c.headers["User-Agent"] = 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.52 Safari/537.17' # c.perform result=JSON.parse(c) puts result["Success"] Please help.

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  • How to change particular column entries in a mysql table when uploading data from csv file?

    - by understack
    I upload data into a mysql table from csv file in a standard way like this: TRUNCATE TABLE table_name; load data local infile '/path/to/file/file_name.csv' into table table_name fields terminated by ',' enclosed by '"' lines terminated by '\r\n' (id, name, type, deleted); All 'deleted' column entries in csv file has either 'current' or 'deleted' value. Question: When csv data is being loaded into table, I want to put current date in table for all those corresponding 'deleted' entries in csv file. And null for 'current' entries. How can I do this? Example: csv file: id_1, name_1, type_1, current id_2, name_1, type_2, deleted id_3, name_3, type_3, current Table after loading this data should look like this: id_1, name_1, type_1, null id_2, name_1, type_2, 2010-05-10 id_3, name_3, type_3, null Edit Probably, I could run another separate query after loading csv file. Wondering if it could be done in same query?

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  • MySQL column names and aliases

    - by user329820
    hi, I have read that after select we use column-names but I have found a statement that was like this: SELECT 'A' FROM T WHERE A = NULL; would you lease help me? thanks (A is a column- name here?) my DBMS is MySQL EDITED : the exact question is this that: Will the above statement produce a row (select all that apply)? Notice that ANSI_NULLS is OFF. I want to know that the above statement will work? because some of you said that we should write IS NULL instead of =null

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  • Flex Builder I want to go from titleWindow to a panel.

    - by dejaninic
    Hi. I'm building an user login page and I want to go from titleWindow to Panel. I'm suing following function but it always takes me back to parentApplication. My question is how can I go to my panel and not to Application page. I know that I'm using parentApplication but what should I use instead??? Here is a part of my code: private function handleLogin(event:ResultEvent):void { Alert.show("You have succesfully logged in.", "Information", Alert.OK, null, null, null, Alert.OK); parentApplication.accountPage.mainService.getAccount(); PopUpManager.removePopUp(this); }

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  • Reversing linked list C

    - by user2976389
    node *rever(node *root) { node *prev = NULL; node *xnew = NULL; while (root != NULL) { xnew = malloc(sizeof(root)); xnew->value = root->value; xnew->next = prev; prev = xnew; root = root->next; } return xnew; } Hello I wrote this linked list reverse function. However it doesn't work(empty response): I suspect it's because of prev index getting overwritten. Could someone explain me whats going on? I know I could find working code on the internet but I wanna know what am I doing wrong. Thanks

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  • trying to use mod_proxy with httpd and tomcat

    - by techsjs2012
    I been trying to use mod_proxy with httpd and tomcat... I have on VirtualBox running Scientific Linux which has httpd and tomcat 6 on it.. I made two nodes of tomcat6. I followed this guide like 10 times and still cant get the 2nd node of tomcat working.. http://www.richardnichols.net/2010/08/5-minute-guide-clustering-apache-tomcat/ Here is the lines from my http.conf file <Proxy balancer://testcluster stickysession=JSESSIONID> BalancerMember ajp://127.0.0.1:8009 min=10 max=100 route=node1 loadfactor=1 BalancerMember ajp://127.0.0.1:8109 min=10 max=100 route=node2 loadfactor=1 </Proxy> ProxyPass /examples balancer://testcluster/examples <Location /balancer-manager> SetHandler balancer-manager AuthType Basic AuthName "Balancer Manager" AuthUserFile "/etc/httpd/conf/.htpasswd" Require valid-user </Location> Now here is my server.xml from node1 <?xml version='1.0' encoding='utf-8'?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- Note: A "Server" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html --> <Server port="8005" shutdown="SHUTDOWN"> <!--APR library loader. Documentation at /docs/apr.html --> <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" /> <!--Initialize Jasper prior to webapps are loaded. Documentation at /docs/jasper-howto.html --> <Listener className="org.apache.catalina.core.JasperListener" /> <!-- Prevent memory leaks due to use of particular java/javax APIs--> <Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" /> <!-- JMX Support for the Tomcat server. Documentation at /docs/non-existent.html --> <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" /> <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" /> <!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html --> <GlobalNamingResources> <!-- Editable user database that can also be used by UserDatabaseRealm to authenticate users --> <Resource name="UserDatabase" auth="Container" type="org.apache.catalina.UserDatabase" description="User database that can be updated and saved" factory="org.apache.catalina.users.MemoryUserDatabaseFactory" pathname="conf/tomcat-users.xml" /> </GlobalNamingResources> <!-- A "Service" is a collection of one or more "Connectors" that share a single "Container" Note: A "Service" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/service.html --> <Service name="Catalina"> <!--The connectors can use a shared executor, you can define one or more named thread pools--> <!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150" minSpareThreads="4"/> --> <!-- A "Connector" represents an endpoint by which requests are received and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html (blocking & non-blocking) Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP) Connector: /docs/apr.html Define a non-SSL HTTP/1.1 Connector on port 8080 <Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- A "Connector" using the shared thread pool--> <!-- <Connector executor="tomcatThreadPool" port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- Define a SSL HTTP/1.1 Connector on port 8443 This connector uses the JSSE configuration, when using APR, the connector should be using the OpenSSL style configuration described in the APR documentation --> <!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150" scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" /> --> <!-- Define an AJP 1.3 Connector on port 8009 --> <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" /> <!-- An Engine represents the entry point (within Catalina) that processes every request. The Engine implementation for Tomcat stand alone analyzes the HTTP headers included with the request, and passes them on to the appropriate Host (virtual host). Documentation at /docs/config/engine.html --> <!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> --> <Engine name="Catalina" defaultHost="localhost" jvmRoute="node1"> <!--For clustering, please take a look at documentation at: /docs/cluster-howto.html (simple how to) /docs/config/cluster.html (reference documentation) --> <!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> --> <!-- The request dumper valve dumps useful debugging information about the request and response data received and sent by Tomcat. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.RequestDumperValve"/> --> <!-- This Realm uses the UserDatabase configured in the global JNDI resources under the key "UserDatabase". Any edits that are performed against this UserDatabase are immediately available for use by the Realm. --> <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> <!-- Define the default virtual host Note: XML Schema validation will not work with Xerces 2.2. --> <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true" xmlValidation="false" xmlNamespaceAware="false"> <!-- SingleSignOn valve, share authentication between web applications Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn" /> --> <!-- Access log processes all example. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="common" resolveHosts="false"/> --> </Host> </Engine> </Service> </Server> now here is the server.xml file from node2 <?xml version='1.0' encoding='utf-8'?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- Note: A "Server" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/server.html --> <Server port="8105" shutdown="SHUTDOWN"> <!--APR library loader. Documentation at /docs/apr.html --> <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" /> <!--Initialize Jasper prior to webapps are loaded. Documentation at /docs/jasper-howto.html --> <Listener className="org.apache.catalina.core.JasperListener" /> <!-- Prevent memory leaks due to use of particular java/javax APIs--> <Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" /> <!-- JMX Support for the Tomcat server. Documentation at /docs/non-existent.html --> <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" /> <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" /> <!-- Global JNDI resources Documentation at /docs/jndi-resources-howto.html --> <GlobalNamingResources> <!-- Editable user database that can also be used by UserDatabaseRealm to authenticate users --> <Resource name="UserDatabase" auth="Container" type="org.apache.catalina.UserDatabase" description="User database that can be updated and saved" factory="org.apache.catalina.users.MemoryUserDatabaseFactory" pathname="conf/tomcat-users.xml" /> </GlobalNamingResources> <!-- A "Service" is a collection of one or more "Connectors" that share a single "Container" Note: A "Service" is not itself a "Container", so you may not define subcomponents such as "Valves" at this level. Documentation at /docs/config/service.html --> <Service name="Catalina"> <!--The connectors can use a shared executor, you can define one or more named thread pools--> <!-- <Executor name="tomcatThreadPool" namePrefix="catalina-exec-" maxThreads="150" minSpareThreads="4"/> --> <!-- A "Connector" represents an endpoint by which requests are received and responses are returned. Documentation at : Java HTTP Connector: /docs/config/http.html (blocking & non-blocking) Java AJP Connector: /docs/config/ajp.html APR (HTTP/AJP) Connector: /docs/apr.html Define a non-SSL HTTP/1.1 Connector on port 8080 <Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- A "Connector" using the shared thread pool--> <!-- <Connector executor="tomcatThreadPool" port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" /> --> <!-- Define a SSL HTTP/1.1 Connector on port 8443 This connector uses the JSSE configuration, when using APR, the connector should be using the OpenSSL style configuration described in the APR documentation --> <!-- <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150" scheme="https" secure="true" clientAuth="false" sslProtocol="TLS" /> --> <!-- Define an AJP 1.3 Connector on port 8009 --> <Connector port="8109" protocol="AJP/1.3" redirectPort="8443" /> <!-- An Engine represents the entry point (within Catalina) that processes every request. The Engine implementation for Tomcat stand alone analyzes the HTTP headers included with the request, and passes them on to the appropriate Host (virtual host). Documentation at /docs/config/engine.html --> <!-- You should set jvmRoute to support load-balancing via AJP ie : <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1"> --> <Engine name="Catalina" defaultHost="localhost" jvmRoute="node2"> <!--For clustering, please take a look at documentation at: /docs/cluster-howto.html (simple how to) /docs/config/cluster.html (reference documentation) --> <!-- <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> --> <!-- The request dumper valve dumps useful debugging information about the request and response data received and sent by Tomcat. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.RequestDumperValve"/> --> <!-- This Realm uses the UserDatabase configured in the global JNDI resources under the key "UserDatabase". Any edits that are performed against this UserDatabase are immediately available for use by the Realm. --> <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/> <!-- Define the default virtual host Note: XML Schema validation will not work with Xerces 2.2. --> <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true" xmlValidation="false" xmlNamespaceAware="false"> <!-- SingleSignOn valve, share authentication between web applications Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.authenticator.SingleSignOn" /> --> <!-- Access log processes all example. Documentation at: /docs/config/valve.html --> <!-- <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="common" resolveHosts="false"/> --> </Host> </Engine> </Service> </Server> I dont know what it is. but I been trying for days

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  • Which programming idiom to choose for this open source library?

    - by Walkman
    I have an interesting question about which programming idiom is easier to use for beginner developers writing concrete file parsing classes. I'm developing an open source library, which one of the main functionality is to parse plain text files and get structured information from them. All of the files contains the same kind of information, but can be in different formats like XML, plain text (each of them is structured differently), etc. There are a common set of information pieces which is the same in all (e.g. player names, table names, some id numbers) There are formats which are very similar to each other, so it's possible to define a common Base class for them to facilitate concrete format parser implementations. So I can clearly define base classes like SplittablePlainTextFormat, XMLFormat, SeparateSummaryFormat, etc. Each of them hints the kind of structure they aim to parse. All of the concrete classes should have the same information pieces, no matter what. To be useful at all, this library needs to define at least 30-40 of these parsers. A couple of them are more important than others (obviously the more popular formats). Now my question is, which is the best programming idiom to choose to facilitate the development of these concrete classes? Let me explain: I think imperative programming is easy to follow even for beginners, because the flow is fixed, the statements just come one after another. Right now, I have this: class SplittableBaseFormat: def parse(self): "Parses the body of the hand history, but first parse header if not yet parsed." if not self.header_parsed: self.parse_header() self._parse_table() self._parse_players() self._parse_button() self._parse_hero() self._parse_preflop() self._parse_street('flop') self._parse_street('turn') self._parse_street('river') self._parse_showdown() self._parse_pot() self._parse_board() self._parse_winners() self._parse_extra() self.parsed = True So the concrete parser need to define these methods in order in any way they want. Easy to follow, but takes longer to implement each individual concrete parser. So what about declarative? In this case Base classes (like SplittableFormat and XMLFormat) would do the heavy lifting based on regex and line/node number declarations in the concrete class, and concrete classes have no code at all, just line numbers and regexes, maybe other kind of rules. Like this: class SplittableFormat: def parse_table(): "Parses TABLE_REGEX and get information" # set attributes here def parse_players(): "parses PLAYER_REGEX and get information" # set attributes here class SpecificFormat1(SplittableFormat): TABLE_REGEX = re.compile('^(?P<table_name>.*) other info \d* etc') TABLE_LINE = 1 PLAYER_REGEX = re.compile('^Player \d: (?P<player_name>.*) has (.*) in chips.') PLAYER_LINE = 16 class SpecificFormat2(SplittableFormat): TABLE_REGEX = re.compile(r'^Tournament #(\d*) (?P<table_name>.*) other info2 \d* etc') TABLE_LINE = 2 PLAYER_REGEX = re.compile(r'^Seat \d: (?P<player_name>.*) has a stack of (\d*)') PLAYER_LINE = 14 So if I want to make it possible for non-developers to write these classes the way to go seems to be the declarative way, however, I'm almost certain I can't eliminate the declarations of regexes, which clearly needs (senior :D) programmers, so should I care about this at all? Do you think it matters to choose one over another or doesn't matter at all? Maybe if somebody wants to work on this project, they will, if not, no matter which idiom I choose. Can I "convert" non-programmers to help developing these? What are your observations? Other considerations: Imperative will allow any kind of work; there is a simple flow, which they can follow but inside that, they can do whatever they want. It would be harder to force a common interface with imperative because of this arbitrary implementations. Declarative will be much more rigid, which is a bad thing, because formats might change over time without any notice. Declarative will be harder for me to develop and takes longer time. Imperative is already ready to release. I hope a nice discussion will happen in this thread about programming idioms regarding which to use when, which is better for open source projects with different scenarios, which is better for wide range of developer skills. TL; DR: Parsing different file formats (plain text, XML) They contains same kind of information Target audience: non-developers, beginners Regex probably cannot be avoided 30-40 concrete parser classes needed Facilitate coding these concrete classes Which idiom is better?

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  • T-SQL Improvements And Data Types in ms sql 2008

    - by Aamir Hasan
     Microsoft SQL Server 2008 is a new version released in the first half of 2008 introducing new properties and capabilities to SQL Server product family. All these new and enhanced capabilities can be defined as the classic words like secure, reliable, scalable and manageable. SQL Server 2008 is secure. It is reliable. SQL2008 is scalable and is more manageable when compared to previous releases. Now we will have a look at the features that are making MS SQL Server 2008 more secure, more reliable, more scalable, etc. in details.Microsoft SQL Server 2008 provides T-SQL enhancements that improve performance and reliability. Itzik discusses composable DML, the ability to declare and initialize variables in the same statement, compound assignment operators, and more reliable object dependency information. Table-Valued ParametersInserts into structures with 1-N cardinality problematicOne order -> N order line items"N" is variable and can be largeDon't want to force a new order for every 20 line itemsOne database round-trip / line item slows things downNo ARRAY data type in SQL ServerXML composition/decomposition used as an alternativeTable-valued parameters solve this problemTable-Valued ParametersSQL Server has table variablesDECLARE @t TABLE (id int);SQL Server 2008 adds strongly typed table variablesCREATE TYPE mytab AS TABLE (id int);DECLARE @t mytab;Parameters must use strongly typed table variables Table Variables are Input OnlyDeclare and initialize TABLE variable  DECLARE @t mytab;  INSERT @t VALUES (1), (2), (3);  EXEC myproc @t;Procedure must declare variable READONLY  CREATE PROCEDURE usetable (    @t mytab READONLY ...)  AS    INSERT INTO lineitems SELECT * FROM @t;    UPDATE @t SET... -- no!T-SQL Syntax EnhancementsSingle statement declare and initialize  DECLARE @iint = 4;Compound Assignment Operators  SET @i += 1;Row constructors  DECLARE @t TABLE (id int, name varchar(20));  INSERT INTO @t VALUES    (1, 'Fred'), (2, 'Jim'), (3, 'Sue');Grouping SetsGrouping Sets allow multiple GROUP BY clauses in a single SQL statementMultiple, arbitrary, sets of subtotalsSingle read pass for performanceNested subtotals provide ever better performanceGrouping Sets are an ANSI-standardCOMPUTE BY is deprecatedGROUPING SETS, ROLLUP, CUBESQL Server 2008 - ANSI-syntax ROLLUP and CUBEPre-2008 non-ANSI syntax is deprecatedWITH ROLLUP produces n+1 different groupings of datawhere n is the number of columns in GROUP BYWITH CUBE produces 2^n different groupingswhere n is the number of columns in GROUP BYGROUPING SETS provide a "halfway measure"Just the number of different groupings you needGrouping Sets are visible in query planGROUPING_ID and GROUPINGGrouping Sets can produce non-homogeneous setsGrouping set includes NULL values for group membersNeed to distinguish by grouping and NULL valuesGROUPING (column expression) returns 0 or 1Is this a group based on column expr. or NULL value?GROUPING_ID (a,b,c) is a bitmaskGROUPING_ID bits are set based on column expressions a, b, and cMERGE StatementMultiple set operations in a single SQL statementUses multiple sets as inputMERGE target USING source ON ...Operations can be INSERT, UPDATE, DELETEOperations based onWHEN MATCHEDWHEN NOT MATCHED [BY TARGET] WHEN NOT MATCHED [BY SOURCE]More on MERGEMERGE statement can reference a $action columnUsed when MERGE used with OUTPUT clauseMultiple WHEN clauses possible For MATCHED and NOT MATCHED BY SOURCEOnly one WHEN clause for NOT MATCHED BY TARGETMERGE can be used with any table sourceA MERGE statement causes triggers to be fired onceRows affected includes total rows affected by all clausesMERGE PerformanceMERGE statement is transactionalNo explicit transaction requiredOne Pass Through TablesAt most a full outer joinMatching rows = when matchedLeft-outer join rows = when not matched by targetRight-outer join rows = when not matched by sourceMERGE and DeterminismUPDATE using a JOIN is non-deterministicIf more than one row in source matches ON clause, either/any row can be used for the UPDATEMERGE is deterministicIf more than one row in source matches ON clause, its an errorKeeping Track of DependenciesNew dependency views replace sp_dependsViews are kept in sync as changes occursys.dm_sql_referenced_entitiesLists all named entities that an object referencesExample: which objects does this stored procedure use?sys.dm_sql_referencing_entities 

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  • Postfix log.... spam attempt?

    - by luri
    I have some weird entries in my mail.log. What I'd like to ask is if postfix is avoiding correctly (according with the main.cf attached below) what seems to be relay attempts, presumably for spamming, or if I can enhance it's security somehow. Feb 2 11:53:25 MYSERVER postfix/smtpd[9094]: connect from catv-80-99-46-143.catv.broadband.hu[80.99.46.143] Feb 2 11:53:25 MYSERVER postfix/smtpd[9094]: warning: non-SMTP command from catv-80-99-46-143.catv.broadband.hu[80.99.46.143]: GET / HTTP/1.1 Feb 2 11:53:25 MYSERVER postfix/smtpd[9094]: disconnect from catv-80-99-46-143.catv.broadband.hu[80.99.46.143] Feb 2 11:56:45 MYSERVER postfix/anvil[9097]: statistics: max connection rate 1/60s for (smtp:80.99.46.143) at Feb 2 11:53:25 Feb 2 11:56:45 MYSERVER postfix/anvil[9097]: statistics: max connection count 1 for (smtp:80.99.46.143) at Feb 2 11:53:25 Feb 2 11:56:45 MYSERVER postfix/anvil[9097]: statistics: max cache size 1 at Feb 2 11:53:25 Feb 2 12:09:19 MYSERVER postfix/smtpd[9302]: connect from vs148181.vserver.de[62.75.148.181] Feb 2 12:09:19 MYSERVER postfix/smtpd[9302]: warning: non-SMTP command from vs148181.vserver.de[62.75.148.181]: GET / HTTP/1.1 Feb 2 12:09:19 MYSERVER postfix/smtpd[9302]: disconnect from vs148181.vserver.de[62.75.148.181] Feb 2 12:12:39 MYSERVER postfix/anvil[9304]: statistics: max connection rate 1/60s for (smtp:62.75.148.181) at Feb 2 12:09:19 Feb 2 12:12:39 MYSERVER postfix/anvil[9304]: statistics: max connection count 1 for (smtp:62.75.148.181) at Feb 2 12:09:19 Feb 2 12:12:39 MYSERVER postfix/anvil[9304]: statistics: max cache size 1 at Feb 2 12:09:19 Feb 2 14:17:02 MYSERVER postfix/smtpd[10847]: connect from unknown[202.46.129.123] Feb 2 14:17:02 MYSERVER postfix/smtpd[10847]: warning: non-SMTP command from unknown[202.46.129.123]: GET / HTTP/1.1 Feb 2 14:17:02 MYSERVER postfix/smtpd[10847]: disconnect from unknown[202.46.129.123] Feb 2 14:20:22 MYSERVER postfix/anvil[10853]: statistics: max connection rate 1/60s for (smtp:202.46.129.123) at Feb 2 14:17:02 Feb 2 14:20:22 MYSERVER postfix/anvil[10853]: statistics: max connection count 1 for (smtp:202.46.129.123) at Feb 2 14:17:02 Feb 2 14:20:22 MYSERVER postfix/anvil[10853]: statistics: max cache size 1 at Feb 2 14:17:02 Feb 2 20:57:33 MYSERVER postfix/smtpd[18452]: warning: 95.110.224.230: hostname host230-224-110-95.serverdedicati.aruba.it verification failed: Name or service not known Feb 2 20:57:33 MYSERVER postfix/smtpd[18452]: connect from unknown[95.110.224.230] Feb 2 20:57:33 MYSERVER postfix/smtpd[18452]: lost connection after CONNECT from unknown[95.110.224.230] Feb 2 20:57:33 MYSERVER postfix/smtpd[18452]: disconnect from unknown[95.110.224.230] Feb 2 21:00:53 MYSERVER postfix/anvil[18455]: statistics: max connection rate 1/60s for (smtp:95.110.224.230) at Feb 2 20:57:33 Feb 2 21:00:53 MYSERVER postfix/anvil[18455]: statistics: max connection count 1 for (smtp:95.110.224.230) at Feb 2 20:57:33 Feb 2 21:00:53 MYSERVER postfix/anvil[18455]: statistics: max cache size 1 at Feb 2 20:57:33 Feb 2 21:13:44 MYSERVER pop3d: Connection, ip=[::ffff:219.94.190.222] Feb 2 21:13:44 MYSERVER pop3d: LOGIN FAILED, user=admin, ip=[::ffff:219.94.190.222] Feb 2 21:13:50 MYSERVER pop3d: LOGIN FAILED, user=test, ip=[::ffff:219.94.190.222] Feb 2 21:13:56 MYSERVER pop3d: LOGIN FAILED, user=danny, ip=[::ffff:219.94.190.222] Feb 2 21:14:01 MYSERVER pop3d: LOGIN FAILED, user=sharon, ip=[::ffff:219.94.190.222] Feb 2 21:14:07 MYSERVER pop3d: LOGIN FAILED, user=aron, ip=[::ffff:219.94.190.222] Feb 2 21:14:12 MYSERVER pop3d: LOGIN FAILED, user=alex, ip=[::ffff:219.94.190.222] Feb 2 21:14:18 MYSERVER pop3d: LOGIN FAILED, user=brett, ip=[::ffff:219.94.190.222] Feb 2 21:14:24 MYSERVER pop3d: LOGIN FAILED, user=mike, ip=[::ffff:219.94.190.222] Feb 2 21:14:29 MYSERVER pop3d: LOGIN FAILED, user=alan, ip=[::ffff:219.94.190.222] Feb 2 21:14:35 MYSERVER pop3d: LOGIN FAILED, user=info, ip=[::ffff:219.94.190.222] Feb 2 21:14:41 MYSERVER pop3d: LOGIN FAILED, user=shop, ip=[::ffff:219.94.190.222] Feb 3 06:49:29 MYSERVER postfix/smtpd[25834]: warning: 71.6.142.196: hostname db4142196.aspadmin.net verification failed: Name or service not known Feb 3 06:49:29 MYSERVER postfix/smtpd[25834]: connect from unknown[71.6.142.196] Feb 3 06:49:29 MYSERVER postfix/smtpd[25834]: lost connection after CONNECT from unknown[71.6.142.196] Feb 3 06:49:29 MYSERVER postfix/smtpd[25834]: disconnect from unknown[71.6.142.196] Feb 3 06:52:49 MYSERVER postfix/anvil[25837]: statistics: max connection rate 1/60s for (smtp:71.6.142.196) at Feb 3 06:49:29 Feb 3 06:52:49 MYSERVER postfix/anvil[25837]: statistics: max connection count 1 for (smtp:71.6.142.196) at Feb 3 06:49:29 Feb 3 06:52:49 MYSERVER postfix/anvil[25837]: statistics: max cache size 1 at Feb 3 06:49:29 I have Postfix 2.7.1-1 running on Ubuntu 10.10. This is my (modified por privacy) main.cf: smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) biff = no append_dot_mydomain = no readme_directory = no smtpd_tls_cert_file = /etc/ssl/certs/smtpd.crt smtpd_tls_key_file = /etc/ssl/private/smtpd.key myhostname = mymailserver.org alias_maps = hash:/etc/aliases alias_database = hash:/etc/aliases myorigin = /etc/mailname mydestination = mymailserver.org, MYSERVER, localhost relayhost = mynetworks = 127.0.0.0/8, 192.168.1.0/24 mailbox_size_limit = 0 recipient_delimiter = + inet_interfaces = all inet_protocols = all home_mailbox = Maildir/ smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination mailbox_command = smtpd_sasl_local_domain = smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous broken_sasl_auth_clients = yes smtpd_tls_security_level = may smtpd_tls_auth_only = no smtp_tls_note_starttls_offer = yes smtpd_tls_CAfile = /etc/ssl/certs/cacert.pem smtpd_tls_loglevel = 1 smtpd_tls_received_header = yes smtpd_tls_session_cache_timeout = 3600s tls_random_source = dev:/dev/urandom smtp_tls_security_level = may

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  • Get to Know a Candidate (9 of 25): Gary Johnson&ndash;Libertarian Party

    - by Brian Lanham
    DISCLAIMER: This is not a post about “Romney” or “Obama”. This is not a post for whom I am voting. Information sourced for Wikipedia. Johnson served as the 29th Governor of New Mexico from 1995 to 2003, as a member of the Republican Party, and is known for his low-tax libertarian views and his strong emphasis on personal health and fitness. While a student at the University of New Mexico in 1974, Johnson sustained himself financially by working as a door-to-door handyman. In 1976 he founded Big J Enterprises, which grew from this one-person venture to become one of New Mexico's largest construction companies. He entered politics for the first time by running for Governor of New Mexico in 1994 on a fiscally conservative, low-tax, anti-crime platform. Johnson won the Republican Party of New Mexico's gubernatorial nomination, and defeated incumbent Democratic governor Bruce King by 50% to 40%. He cut the 10% annual growth in the budget: in part, due to his use of the gubernatorial veto 200 times during his first six months in office, which gained him the nickname "Governor Veto". Johnson sought re-election in 1998, winning by 55% to 45%. In his second term, he concentrated on the issue of school voucher reforms, as well as campaigning for marijuana decriminalization and opposition to the War on Drugs. During his tenure as governor, Johnson adhered to a stringent anti-tax and anti-bureaucracy policy driven by a cost–benefit analysis rationale, setting state and national records for his use of veto powers: more than the other 49 contemporary governors put together. Term-limited, Johnson could not run for re-election at the end of his second term. As a fitness enthusiast, Johnson has taken part in several Ironman Triathlons, and he climbed Mount Everest in May 2003. After leaving office, Johnson founded the non-profit Our America Initiative in 2009, a political advocacy committee seeking to promote policies such as free enterprise, foreign non-interventionism, limited government and privatization. The Libertarian Party is the third largest political party in the United States. It is also identified by many as the fastest growing political party in the United States. The political platform of the Libertarian Party reflects the ideas of libertarianism, favoring minimally regulated markets, a less powerful state, strong civil liberties (including support for Same-sex marriage and other LGBT rights), cannabis legalization and regulation, separation of church and state, open immigration, non-interventionism and neutrality in diplomatic relations (i.e., avoiding foreign military or economic entanglements with other nations), freedom of trade and travel to all foreign countries, and a more responsive and direct democracy. Members of the Libertarian Party have also supported the repeal of NAFTA, CAFTA, and similar trade agreements, as well as the United States' exit from the United Nations, WTO, and NATO. Although there is not an officially labeled political position of the party, it is considered by many to be more right-wing than the Democratic Party but more left-wing than the Republican Party when comparing the parties' positions to each other, placing it at or above the center. In the 30 states where voters can register by party, there are over 282,000 voters registered as Libertarians. Hundreds of Libertarian candidates have been elected or appointed to public office, and thousands have run for office under the Libertarian banner. The Libertarian Party has many firsts in its credit, such as being the first party to get an electoral vote for a woman in a United States presidential election. Learn more about Gary Johnson and Libertarian Party on Wikipedia.

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  • How to set default xrandr settings?

    - by echo-flow
    I'm trying to enable dual monitors in Ubuntu. This is working fine, but every time I do it, desktop effects is disabled. I think I've found the reason why, though: https://wiki.ubuntu.com/X/Config/Multihead/ As with the GNOME XRandR configuration method, setting Virtual to too large a value may result in a loss of hardware acceleration, and thus an inability to use Compiz and its desktop effects. When I use the GNOME monitor applet, or the Monitors configuration in the System menu, the default xrandr settings puts the second monitor to the right of the first, and, as I found with this bug, for most monitors this creates a virtual desktop larger than the maximum 2048 horizontal resolution needed for hardware acceleration on my netbook hardware. So, it seems like if I can modify xrandr's default settings so that it places the new desktop above or below (north or south of) the main LVDS display, then hardware acceleration, and therefore compiz will continue to work. Can anyone tell me, what is the easiest way to achieve this? UPDATE: I have confirmed that multihead support with desktop effects and hardware acceleration works when I move the external monitor display north of the main LVDS display. Right now this involves the following process: plugging in the external monitor, starting the Monitors configuration menu, desktop effects are disabled automatically (and all of the windows on my workspaces are moved to the first workspace), repositioning the external display so that it is north of LVDS display and clicking apply, and then navigating to the Appearance menu and telling it to reenable desktop effects. Is there a simpler way do this? UPDATE 2: OK, so I thought that perhaps the GNOME Monitors configuration screen was trying to be clever, and might be disbling desktop effects. So, I just tried using the xrandr command-line client instead, as follows: xrandr --output VGA1 --above LVDS1 When I do that, desktop effects are still disabled, and I need to manually reenable them. This, despite the fact that hardware acceleration works, and there is never a point where hardware acceleration stops working because the horizontal dimension of the virtual display is too large. So what program is trying to be clever, and is turning off desktop effects when it doesn't need to? And how do I make it stop? If there were a way to re-enable desktop effects from the command line, which I could then put into a script along with the proper xrandr invocation, I would accept that as a workaround. UPDATE 3: OK, here's my script to enable a second monitor with desktop effects. It might be evil, I'm not sure: second-monitor.sh xrandr --output VGA1 --above LVDS1 sleep 3 compiz --replace & The sleep statement might not be necessary. If there's a better way to do this, please let me know. UPDATE 4: This is a Dell Mini Inspiron 1012. Here are my system specifications: lspci -vv 00:02.0 VGA compatible controller: Intel Corporation N10 Family Integrated Graphics Controller Subsystem: Dell Device 041a Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Interrupt: pin A routed to IRQ 29 Region 0: Memory at f0b00000 (32-bit, non-prefetchable) [size=512K] Region 1: I/O ports at 18d0 [size=8] Region 2: Memory at d0000000 (32-bit, prefetchable) [size=256M] Region 3: Memory at f0900000 (32-bit, non-prefetchable) [size=1M] Capabilities: <access denied> Kernel driver in use: i915 Kernel modules: i915 00:02.1 Display controller: Intel Corporation N10 Family Integrated Graphics Controller Subsystem: Dell Device 041a Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Region 0: Memory at f0b80000 (32-bit, non-prefetchable) [size=512K] Capabilities: <access denied> lsmod | grep i915 i915 287458 2 drm_kms_helper 29329 1 i915 drm 162409 3 i915,drm_kms_helper intel_agp 24375 2 i915 i2c_algo_bit 5028 1 i915 video 17375 1 i915

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  • Whether to use UNION or OR in SQL Server Queries

    - by Dinesh Asanka
    Recently I came across with an article on DB2 about using Union instead of OR. So I thought of carrying out a research on SQL Server on what scenarios UNION is optimal in and which scenarios OR would be best. I will analyze this with a few scenarios using samples taken  from the AdventureWorks database Sales.SalesOrderDetail table. Scenario 1: Selecting all columns So we are going to select all columns and you have a non-clustered index on the ProductID column. --Query 1 : OR SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR ProductID =709 OR ProductID =998 OR ProductID =875 OR ProductID =976 OR ProductID =874 --Query 2 : UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 709 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 998 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 875 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 976 UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 874 So query 1 is using OR and the later is using UNION. Let us analyze the execution plans for these queries. Query 1 Query 2 As expected Query 1 will use Clustered Index Scan but Query 2, uses all sorts of things. In this case, since it is using multiple CPUs you might have CX_PACKET waits as well. Let’s look at the profiler results for these two queries: CPU Reads Duration Row Counts OR 78 1252 389 3854 UNION 250 7495 660 3854 You can see from the above table the UNION query is not performing well as the  OR query though both are retuning same no of rows (3854).These results indicate that, for the above scenario UNION should be used. Scenario 2: Non-Clustered and Clustered Index Columns only --Query 1 : OR SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR ProductID =709 OR ProductID =998 OR ProductID =875 OR ProductID =976 OR ProductID =874 GO --Query 2 : UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 709 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 998 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 875 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 976 UNION SELECT ProductID,SalesOrderID, SalesOrderDetailID FROM Sales.SalesOrderDetail WHERE ProductID = 874 GO So this time, we will be selecting only index columns, which means these queries will avoid a data page lookup. As in the previous case we will analyze the execution plans: Query 1 Query 2 Again, Query 2 is more complex than Query 1. Let us look at the profile analysis: CPU Reads Duration Row Counts OR 0 24 208 3854 UNION 0 38 193 3854 In this analyzis, there is only slight difference between OR and UNION. Scenario 3: Selecting all columns for different fields Up to now, we were using only one column (ProductID) in the where clause.  What if we have two columns for where clauses and let us assume both are covered by non-clustered indexes? --Query 1 : OR SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR CarrierTrackingNumber LIKE 'D0B8%' --Query 2 : UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT * FROM Sales.SalesOrderDetail WHERE CarrierTrackingNumber  LIKE 'D0B8%' Query 1 Query 2: As we can see, the query plan for the second query has improved. Let us see the profiler results. CPU Reads Duration Row Counts OR 47 1278 443 1228 UNION 31 1334 400 1228 So in this case too, there is little difference between OR and UNION. Scenario 4: Selecting Clustered index columns for different fields Now let us go only with clustered indexes: --Query 1 : OR SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 OR CarrierTrackingNumber LIKE 'D0B8%' --Query 2 : UNION SELECT * FROM Sales.SalesOrderDetail WHERE ProductID = 714 UNION SELECT * FROM Sales.SalesOrderDetail WHERE CarrierTrackingNumber  LIKE 'D0B8%' Query 1 Query 2 Now both execution plans are almost identical except is an additional Stream Aggregate is used in the first query. This means UNION has advantage over OR in this scenario. Let us see profiler results for these queries again. CPU Reads Duration Row Counts OR 0 319 366 1228 UNION 0 50 193 1228 Now see the differences, in this scenario UNION has somewhat of an advantage over OR. Conclusion Using UNION or OR depends on the scenario you are faced with. So you need to do your analyzing before selecting the appropriate method. Also, above the four scenarios are not all an exhaustive list of scenarios, I selected those for the broad description purposes only.

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