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Great Reads

Inverted Indexes: A Scala Step-by-Step Implementation Guide

by Leonid Chashnikov

Discover an efficient way to implement document search using inverted index

SQL Index Manager – Free GUI Tool for Index Maintenance on SQL Server and Azure

by Sergii Syrovatchenko

Open source index maintenance tool for SQL Server and Azure

Database performance optimization part 2 (Index maintenance)

by Kanasz Robert

In this second part of series of articles about database performance optimization I will discuss about index maintenance.

Database performance optimization part 1 (Indexing strategies)

by Kanasz Robert

In this first part of series of articles about database performance optimization I will discuss about indexing strategies and index maintenance.

Latest Articles

Inverted Indexes: A Scala Step-by-Step Implementation Guide

by Leonid Chashnikov

Discover an efficient way to implement document search using inverted index

SQL Index Manager – Free GUI Tool for Index Maintenance on SQL Server and Azure

by Sergii Syrovatchenko

Open source index maintenance tool for SQL Server and Azure

InputSplit Indexing on Mapreduce

by Antoine Amend

Create custom indexes for improving Mapreduce performance

by Ronnie Mukherjee

B-tree Indexes

All Articles

Indexes

Sort two arrays with corresponded indexes

25 Apr 2012 by VJ Reddy

The Array.Sort(Of TKey, TValue) Method (TKey(), TValue(), IComparer(Of TKey)) explained here http://msdn.microsoft.com/en-us/library/x8kwfbye.aspx[^] can be used for this purpose. In the present case, as the sorting is to be done in Descending order IComparer is required, which is explained here...

Indexed Vertex Blending with the Direct3D Pipeline

27 Jun 2012 by bearsomg

Hello. I am currently working on a rendering engine which is meant to render character animations. Right now I am working on vertex blending to make the body parts move with the bones.For each vertex declaration, I have a short that represents the first bone's weight, and 2 shorts...

Find index of a String in a String Array

18 Oct 2013 by Harshil_Raval

Hi,try this.int TextIndex = Array.FindIndex(inputstringarray, m => m == "Is");//replace "Is" with your other desired textHope it helps you.

Find index of a String in a String Array

18 Oct 2013 by BillWoodruff

I'd like to suggest you use the form of the String.Split method that removes "empty entries:"// defining the char[] used to Split in advance // can save memory if you are using it repeatedlyprivate char[] splitCharAry = new char[] { '\'' };string str =...

List<object> with indexed String

23 Jan 2015 by Tomas Takac

Use Dictionary[^]:public Dictionary data = new Dictionarypublic object Test(string indexName){ return data[indexName];}

Inverted Indexes: A Scala Step-by-Step Implementation Guide

25 Sep 2023 by Leonid Chashnikov

Discover an efficient way to implement document search using inverted index

SQL Server fulltext index auto population?

16 Aug 2011 by Zach Swanson

I have a table with a full-text index that is essentially a denormalized view of several tables that is automatically updated when any of the base tables are updated via triggers. This table is primarily used for a nightly operation, but I would like to use it for more real-time things if I...

PHP Error on my Primary content page

20 Nov 2011 by Sergey Alexandrovich Kryukov

You need to show the HTML code with menu you use to get to this "primary content page" or your AJAX call if you use any, but basically the problem is simple:The PHP variable _GET is an associated container of form data using HTTP method "get" indexed by keys each representing a name...

Sort two arrays with corresponded indexes

25 Apr 2012 by Member 8312096

Dear All,I have two arrays (array1 and array2)with double type data. I want to sort array1 to ascending order, and array2 with corresponding to the array1 indexes. Is this possible? Example below,Array1(0) = 2.30 Array1(1) = 4.20Array1(2) = 1.90Array1(3) = 0.20Array1(4) = 0.88...

DataGridview seleted Rows indexes ?

12 Dec 2012 by Aarti Meswania

as below...dim First_selected_row_Ind = dataGridView1.SelectedRows(0).Indexdim Last_selected_row_Ind = dataGridView1.SelectedRows(datagridview1.selectedrows.count-1).IndexHappy Coding!:)

what is meant by indexers in c#.net

16 Jan 2013 by __TR__

Google[^] gave me about 1,140,000 results when i entered this question's subject in search query. Next time you post a question in this forum make sure you have googled for the information. If you are not good in searching for information through google go through the below article. You might...

java.lang.IndexOutOfBoundsExce...

22 Apr 2013 by Niral Soni

I have made some changes to your block, have a look and let me know if that works...Rather then going backward (i-1, i-2), I rewrite the logic for going forward (i, i+1).So, when you are at i=0, you actually calculates slope for (i and i+1) to a max value of 9 (happyRating.size() -...

Adding more columns slows down the SELECT query

27 Jun 2013 by ArunRajendra

You can improve the performace by creating multiple index with different combinations of columns as per the need. The other option is if you want to fetch the columns let's say colB, colC, colD only based on colA index then you can use include while creating the index as shown in the example....

How to properly index hstore tags column to faster search for keys

6 Jul 2013 by Radu-Stefan Zugravu

Hi,I imported a large area of OpenStreetMap's planet.osm file into a postgresql database. The database contains a table called nodes. Each node has a geometry column called geom and a hstore column called tags. I need to extract nodes along a line that have certain keys in the tags column....

Find index of a String in a String Array

18 Oct 2013 by Timberbird

Ok, we have Array static member, we have for cycle... what are we missing? Right, Linq expressions! :)You could try the following:int[] indexes = inputstringarray.Select((str, index) => str.Equals("Is", StringComparison.InvariantCulture) ? index : -1).Where(iElement => iElement >=...

Hide certain row from combobox C#

17 Dec 2013 by An@nd Rajan10

for (int i = 0; i

SelectedIndexChanged

Difference between clustered and non clustered index in sql server

14 Jan 2014 by Christian Graus

While I agree that the best way to answer this would have been google, I will just add that a clustered index is super fast for searches, and slows down deletes and ( to a lesser degree ) changes to data. If you have a primary key on your table, it is a clustered index by default, so if you...

using position (index) number to find words in text files? java

2 May 2015 by Richard MacCutchan

First you will need to use a StreamReader class to read the file. You will also need some way of identifiying where each paragraph ends. Once you have that then you can use the String class to split the paragraph into an array of words. That will allow you to find a specific item by index. You...

How to check if a value exists in any key in PHP array

3 Mar 2017 by Peter Leow

Try this:or demo[^]

Sql database file not created and not opened

14 May 2017 by OriginalGriff

You can't attach the database for the reason given in the error message: "the server was not found or was not accessible". Start by looking at your connection string and find out what SQL instance you are trying to connect to. Then look at what the instance(s) you have available are called, and...

Tower of hanoi, index error

30 Oct 2017 by OriginalGriff

If you get an "Index out of range" error, it means that you have tried to access an array or other collection, but the index number you tried to fetch is not in the collection - it's either negative, or larger than the number of elements in the collection minus one (because indexes start at...

Invalid index when passing parameter to crystal report in VB.NET

28 Mar 2018 by an0ther1

As per the comment above by Richard, the Report cannot locate a parameter with the name "Deal_Date" In my opinion you are better off looping through the Parameter fields and checking the name before you populate, the following will work; If(crRpt.DataDefinition.ParameterFields.Count > 0) Then ...

Two index of a table can be activated at the same time

26 Apr 2018 by OriginalGriff

One way to do it might be to use a computed column and index that: How to create indexes on SQL Server computed columns[^] Other than that, you can have multiple indexes on the same table. It's really going to depend on what you are doing with the table, there aren't any "one size fits all"...

Two index of a table can be activated at the same time

26 Apr 2018 by Richard Deeming

Check out the estimated or actual execution plan in SSMS to see which index is being used: Display the Estimated Execution Plan | Microsoft Docs[^] Display an Actual Execution Plan | Microsoft Docs[^] You can create an index on multiple columns, which might help. However, since you're selecting...

Two index of a table can be activated at the same time

26 Apr 2018 by Wendelius

First of all, you don't activate indexes. SQL Server optimizer makes the decision if an index (or several indexes) will be used or not. Your job is to ensure that you have proper indexes in place, but also that you don't over-index since that would degrade performance for modifications. Having...

How to index an exisiting code first database?

22 Apr 2020 by ishan_shah

In the migration, You should add your index creation to the up() method and a drop statement to the Down() method to enable downgrading the database schema namespace TestLib.Migrations { using System.Data.Entity.Migrations; public...

How should I change my code to eliminate the index error

16 Jun 2022 by OriginalGriff

Indexes in Python (like most other languages) start at zero, and run to the number of elements minus one. So a three element array arr would have legitimate indexe of 0, 1, and 2 only - any other value is outside the bounds of the array and will...

[Solved] how do we properly down-cast an array of base object? Can we truly downcast/type-punning from base type to derive type and then properly call its non-constexp or const mem-func?

18 Jul 2022 by CPallini

If the classes DeriveOne, DeriveTwo derive polymorphically from Base then you may use dynamic_cast, e.g.std::cout (base[0]))->getStr()

Unable to access website

16 Oct 2023 by Dave Kreskowiak

Your code is assuming this line: ds = ObjAdd.DisplayPrayerTime(); is returning a bunch of rows. It does not check to see if any tables or rows have been returned by DisplayPrayerTime. Why is it not returning rows? Nobody can tell you because...

SQL Server fulltext index auto population?

16 Aug 2011 by Wendelius

Most likely the background population you saw is another term for tracking changes.If you add large amount of data in your nightly operations, I would suggest that you drop the index before nightly operations, do the operations and then create the index again (so not using rebuild). When...

PHP Error on my Primary content page

20 Nov 2011 by Anthony Bond

I'm working on a php website for my class. I'm currently in the process of learning and understanding the switch code, and how it utilizes the menukey index. For some reason I keep getting this error on my page "Notice: Undefined index: menukey in D:../../../../index.php on line 24". However...

Building document store with search capability

26 Jan 2012 by skyforever

Hi all,I need to create a document store with search capabilities. Sounds simple... That means that I have documents which I need to store in database. I thought about CouchDB, and about few other document-oriented databases, but I'm still not sure what would be the best solution.On...

SQL Efficiency Question

5 Mar 2012 by Richard Algeni Jr

Hi folks,This is a 'best practices' question. I am replacing an application that used the Unidata (Pick like) database. The application itself is a messaging process, which is not a problem, neither is the setup of the table. My question is of an index nature. In Unidata, there is a small...

SQL Efficiency Question

5 Mar 2012 by snorkie

Rich,My experience is with SQL Server 2005 for what it's worth. I don't know that combining the two tables is a good idea. Indexing is a bit of an expensive operation in terms of adding and removing records. Once the index is complete, the searching and retrieving of records is quite fast....

SQL Efficiency Question

6 Mar 2012 by Richard Algeni Jr

Thanks for the info Hogan! I'll do some testing to see what's best. I wasn't sure if I had completely run off the tracks!

idea to happen sql reports on separate database than same database that is serving web applica...

17 Apr 2012 by Mohammad A Gharakhanlou

We use sql reports in a dot.net web application but some of our reports are heavy and involve more table join and columns. as u know we cannot index all the involved columns(performance problem).these reports impact web application performance. now we are running reports against the same...

SQL-Server-2005

idea to happen sql reports on separate database than same database that is serving web applica...

22 Apr 2012 by milenalukic

Hi,I had this issue personnaly and did not have the luxory of an additional server.My reports needed to be correct as of close of business the previous day. So what I did was to perform overnight jobs with the complex queries in question and storing the results in a flat file. Then I could...

SQL-Server-2005

Index logic in combobox ?

24 Jul 2012 by Bernhard Hiller

The connection between the items in the first combobox and the second combobox is modelled also somewhere else (at least ought to be), e.g. in a table in a database or in a linking class.That means, in the SelectedIndexChanged event of the first combobox (note: check that it is not -1!), you...

How do i Find row index in datatable using vb.net?

29 Jul 2012 by sant.rajas

Thanks strogg. You are absolutely correct.Actually my problem is I am dynamically setting the data like SerialNumber etc in newly created row which gets updated into datasource and then goes to the client side where this new row is reflected in datagrid.I have an idea about solving this...

Indexed Vertex Blending with the Direct3D Pipeline

22 Aug 2012 by Debdatta Basu

There could be a host of different reasons for this. First of all, two bone weights is too low. 4 is respectable. But this is most probably not the problem.The problem could be bad math in your vertex shader. In any case, you would need to provide more info for us ti diagnose the problem....

Difference between clustered and non clustered index in sql server

19 Sep 2012 by Tadit Dash (ତଡିତ୍ କୁମାର ଦାଶ)

Please go through 1. Clustered and Non-Clustered Index in SQL 2005[^].2. Overview of SQL Server 2005/2008 Table Indexing (Part-1)[^]3. Database performance optimization part 1 (Indexing strategies)[^]4. Speeding up database access - Part 3: Fixing missing indexes[^]

i have method to add row i get my data from database , i want to save row in my table

4 Oct 2012 by Mohannad Khaled Maglad

Datatable dt2=getEmaployeeData(); foreach (DataRow erow in dt2.Rows) { employeeid = erow["employee_code"].ToString(); employeeName = erow["employee_name"].ToString(); hodID =...

i have method to add row i get my data from database , i want to save row in my table

4 Oct 2012 by fjdiewornncalwe

You are accepting changes before adding the new row. Nothing will happen then.DataRow sh*t = finleTable.Rows[i];finleTable.AcceptChanges();finleTable.Rows.Add(dr);Try this:DataRow sh*t = finleTable.Rows[i];finleTable.Rows.Add(dr);finleTable.AcceptChanges();

C sharp Class Logic Issue

21 Nov 2012 by sachinDabas

Hi All, I am facing one issue can you give me suggestions.Question:Suppose we have a classClass A{ string Fun1(){//some logic return String}; Int Fun2(){//some logic return int }; objClassXyz Fun3(//some logic return object of class ClassXyz);}Now I will inherit...

Performance Issue On SQL

11 Dec 2012 by praveen.victor

Hi,I need to copy a parent tabel into another child table.where the parent table contains a lot of records i.e about 22224171 records.I need to decress the copying time. i have already applied index to 4 columns in the child table.Could any one help me to solve this performance...

Performance Issue On SQL

11 Dec 2012 by Dylan Morley

Copy large amounts of data into a table is a balancing act between the data you are inserting and the indexes on that table. Have a look at this question on stack overflow...http://stackoverflow.com/questions/6955456/drop-rebuild-indexes-during-bulk-insert[^]"There is overhead in...

DataGridview seleted Rows indexes ?

12 Dec 2012 by Ahmed.ganainy

Dear professionals, simple dummy question from beginner. in my app the user will select the rows in the data GridView.i want to get the start and end indexes of his selection.

DataGridview seleted Rows indexes ?

12 Dec 2012 by Ahmed.ganainy

If DGV1.SelectedRows.Count > 0 Then ENDROW = DGV1.SelectedRows(0).Index STARTROW = DGV1.SelectedRows(DGV1.SelectedRows.Count - 1).Index Dim TEMPROW As Integer If ENDROW

Clustered and Non-clustered indexes in sql server

8 Mar 2013 by Manish Sahdeva

Dear All, could anyone suggest me the good link to understand the index in sql server, i am trying to understand from usual articles but, i can not, I do not want theory, i just want logical working of clustered and non-clustered index in sql server.Any help will be highly appreciated.

Clustered and Non-clustered indexes in sql server

8 Mar 2013 by Davidduraisamy

This will be understandable..http://www.c-sharpcorner.com/uploadfile/nipuntomar/clustered-index-and-non-clustered-index-in-sql-server/[^]Clustered and Non-Clustered Index in SQL 2005[^]

java.lang.IndexOutOfBoundsExce...

22 Apr 2013 by GaryDoo

Hi folks, hoping someone can help.I have an arraylist of Integers. When there is a button click the data in the text field gets converted and added to the array list as an int. You can see, once there has been ten submissions (counter takes care of that) it calls the function train();. Here...

java.lang.IndexOutOfBoundsExce...

22 Apr 2013 by Filipe Marques

Hi,There are same issues in your code.1- The counter variable is never reseted (may be can be set to zero in another function)2- You only call the train function when counter is equal to 10 but your array only has 9 items or less, if the rating is not between 0 and 113- Another thing,...

Why did increase Estimated subtree cost when using non clustered index in sql server 2008?

12 May 2013 by Code-Hunt

http://social.msdn.microsoft.c...

MySQL Indexing 2 billion rows

4 Jun 2013 by Member 9562469

First off this is MySQL 5.6 and MyISAM tables, run on a desktop with a 4.2GHZ I7 16GB RAM and RAID 0 Drives. I have a few large tables anywhere between 250 million and 2 billion rows, with sizes ranging between 20 and 150 GB. How long should it take to add indexes, mostly on VARCHAR or...

MySQL Indexing 2 billion rows

4 Jun 2013 by Ron Beyer

There isn't a good answer for this, what I would do is to make a subset of your table (let's say 100,000 rows) and add indexes to it, while timing it. Then extrapolate out for the size of your other tables and that should give you a rough answer.

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

4 Jun 2013 by Member 10033107

Hi Everyone!I have trouble in this error wherein i didnt understand how i will adjust this command..please help me and thank you in advance...Dim Item As ListViewItem = DirectCast(lvsummary.Items(0), ListViewItem) Dim txtid As TextBox = DirectCast(Item.FindControl("idTextbox"),...

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

4 Jun 2013 by Sergey Alexandrovich Kryukov

You have only one index here, 0. Therefore, lvsummary.Items element count it zero. Before accessing any array or collection with zero-based indexing, make sure there is at least one element.—SA

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

4 Jun 2013 by _Amy

This exception is obvious. You are trying to access a member of an collection which does not exist. For e.g. your ListView is not having any item or it is null but still if you are trying to access the ListItem. This will throw an error. Try stepping through your code and check the value of...

Adding more columns slows down the SELECT query

27 Jun 2013 by Bogdan Ionesku

Clustered indexes are stored along with data while non-clustered indexes are not. Mixing them in SELECT statement is never a smart choice.

How does SQL Server suggests the order of columns in Missing Index Suggestion

31 Dec 2013 by shadyrocks08

Hi GuysI am looking for an understanding or an alogorithm that gives the orders of the columns in Missing Index Suggestion in SQL Server 2008/2012.If any one knows is there any alogrithm that SQL Server uses for it?.Need some deep information on this as i m working on a part where there...

How does SQL Server suggests the order of columns in Missing Index Suggestion

31 Dec 2013 by Christian Graus

If order matters, you need a way to sort them. if you don't, order is not guaranteed, because sets do not have an order.If there's no way to sort them, then the order is random and has no reason to be critical.

Composite index or single column index

23 Jan 2014 by MONISH K M

Hi friends,I want to index some columns in our database. Always, I have SQL with multiple columns in my where clause.All of those columns are already indexed individually I am thinking to drop these single column indexes and want to create composite index for these columns i.e....

Composite index or single column index

23 Jan 2014 by Tejas Vaishnav

please have a look around this...http://grahitanusantara.blogspot.in/2011/06/single-vs-composite-indexes.html[^]http://www.nullskull.com/q/10140481/difference-between-composite-index-and-covering-index.aspx[^]

Getting Indexes of Colors from rows in Image

9 Feb 2014 by Kornfeld Eliyahu Peter

Let me Google that for you...[^]

image-processing

How to check performance(Speed, Space used, etc) of My Primary Indexing Technique

1 Mar 2014 by Mayank Patel

Hello,I have written code of My Indexing Technique in "C" language.(or Java, C Preferred) I also need to compare it with existing Primary Indexing technique(like B+ Tree). I need to know,1) Is it possible to do this in MySQL or MsSQL(or any open source DBMS software)? I need to...

How to check performance(Speed, Space used, etc) of My Primary Indexing Technique

2 Mar 2014 by shailesh91082

if you are using windows, then "perfmon" can give you the performance data.http://blogs.msdn.com/b/securitytools/archive/2009/11/04/how-to-use-perfmon-in-windows-7.aspx[^]

Sorting Columns and find Standard Deviation

4 Mar 2014 by FarhanShariff

Language: C# Windows Form/Console DataTable Shown Below1.Sort the Columns in Ascending Order.(smallest to largest.)2.After sorting find x1 and x2 index number - a. x1 = 0.90*N b. x2 = 0.10*N N= +...

Sorting Columns and find Standard Deviation

4 Mar 2014 by GaneshKale22

Try ThisDataTableName.DefaultView.Sort = "Column ASC";

How can I improve the performance of this query using indexes?

24 Jun 2014 by SovereignX

Here's my query: SELECT 'Id' = el.id, 'DB Time Stamp' = convert(nvarchar(50), el.db_datetime), 'Local Time Stamp' = convert(nvarchar(50), el.local_datetime), 'Event' = e.name, 'Sub Campaign' = sc.title, 'Company' = a.company_name, 'Contact' = c.first_name + '...

How can I improve the performance of this query using indexes?

24 Jun 2014 by Vedat Ozan Oner

Actually, I won't give you the direct answer, but I'll tell you what I would do in such a case. Start with joining two tables (event_log, events). No conversion, no other tables, no ordering. Then step by step add other tables, then apply other criteria, ordering, conversion, etc. Which change...

Find Sub Reports and their Page Number in Main Report in SQL Reporting Services .rdl

10 Jul 2014 by JR009

Hello, I have a main report (.rdl file) containing multiple sub-reports. Now i need to create the table of contents or index, which display the Name of sub-reports and their starting page number, at the beginning of the main report.Like as follow :TABLE OF CONTENTSSub-Report...

Optimise searching Mechanism based on date time datatype

5 Aug 2014 by Kunal Ved

I have a table with above 100,000 records,The searching mechanism has grown slower as the data in the table is piling on. the schema is some what like ENQ_ID FACULTY Date 141 2411 2004-03-21 1412 ...

SQL-Server-2008R2

Optimise searching Mechanism based on date time datatype

5 Aug 2014 by Kunal Ved

------------------------------...

SQL-Server-2008R2

Need to optimize mssql query for fastest speed

6 Aug 2014 by coded007

Try with below query i am not sure it will give data under 5 seconds but performance will improve.create table #oz ( id int, from_sto_move bit, product_id int, [date] datetime, qty_orlogo decimal(30, 10), qty_zarlaga decimal(30, 10), cost_prev decimal(30, 10)) print 'Query started...

Grid View Page index click problem(same page load every time).

25 Sep 2014 by Herman<T>.Instance

In your code it is not clear if the GridView has the AllowPaging = true. This might be set in the .aspx fileYou don't set the PageIndex property for the grdlistTeam GridView in the BindRecentMatches() method:You should add a property in your class so you can use the NewPageIndex value from...

Grid View Page index click problem(same page load every time).

25 Sep 2014 by Santhosh Babu Mahimairaj

Check the below points1. Check GridView's AllowPaging Propery to True.2 .Check Fire GridView's PageIndexChanging event.

how to prevent from indexing file of specific Directory in Asp.Net

30 Nov 2014 by Seyed Ahmad Mirzaee

hi allin htaccess we able to prevent from Indexing file of DirectoryOptions -Indexesbut i need for asp.Nethtaccess file use in php but i need in Asp.NetThanks so Much

how to prevent from indexing file of specific Directory in Asp.Net

30 Nov 2014 by DamithSL

you can set this on your web config file, check below sample web config if you want to enable directory browsing set directoryBrowse as true, if you host your web application in IIS you can follow the below steps...

List<object> with indexed String

23 Jan 2015 by spaika

usually WE try to return the object of the List along with the integer index like example below:public List data = new List();public object Test(int index){ return data[index];}But I would like to do is, I wanting to replace the indexed integer to...

List<object> with indexed String

23 Jan 2015 by spaika

using System;using System.Collections.Generic;class Program{ static void Main() { Dictionary dictionary = new Dictionary(); dictionary.Add("apple", 1); dictionary.Add("windows", 5); // See whether Dictionary contains...

Table size growing .what are performance techniques? - Interview questions

22 Apr 2015 by pratap420

Hi Guys,I am facing few questions in interview,every time i am telling something but interviewer expecting some thing more.So I want to get it know from Experts some possible answers 1.There is a table which is keep on growing (let's say table has 10 millions records) so that performance...

SQL-Server-2008R2

using position (index) number to find words in text files? java

2 May 2015 by Reem Suliman

I have texts (Paragraphs) and I want to replace each of annotated wrong word in the paragraph with the correct word indicated by the position (index) number of the wrong word and i need to do it for each paragraph... So, what method should I use to search by index number? thank...

mongodb indexing on nested document

18 Jul 2015 by cy163@hotmail.com

I am storing time series data (machine monitoring data) with MongoDB. The data model looks like the following,which is inspired by the internet article "MongoDB as a Time Series Database"{ timestamp_hour: ISODate("2013-10-10T23:00:00.000Z"), type: “Voltage”, values: { 0: { 0:...

Fatal error: Call to a member function get() on a non-object in .../index.php on line 97

31 Jul 2015 by Salman _Memon

have you load the model and data base in controller ? like $this->load->database();//data base load

MySQL Indexing, best way?

25 Aug 2015 by Andy Lanng

It depends:Fewer indexes = faster insert / update, slower queryMore indexes = slower insert / update, faster queryYou have to weigh it up against the common usage.One way to reduce search time is to have a term table (pretty much every single word used) and a link table to the rows...

C# convert ArrayList to 2D int array

17 Dec 2015 by Member 11380736

c#Is it possible to convert a ArrayList to a 2D int[1,13] array ?The ArrayList is all numbers like "1111100000000", "0111110000000".And I want them to look like this:int[,] a = { { 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 }, { 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 }, { 0, 0, 1, 1, 1,...

C# convert ArrayList to 2D int array

17 Dec 2015 by BillWoodruff

You could use Linq to create an int[],[] Array:// requiredusing System.Linq;int[],[] jaggedArray = aList.ToArray().Select(elem => elem.ToString().Select(ch => (int)Char.GetNumericValue(ch)).ToArray()).ToArray()// orint[],[] jaggedArray = aList.ToArray().Select(elem =>...

c# check if index's in string[] are next to each other in array

25 Dec 2015 by OriginalGriff

Get the indexes into an array.Sort the array.If the values in the array are all a single increment from the previous value, the strings are all next to each other.There is an Array.Sort method in .NET, and a simple for or foreach loop will check the results.

Multi dimensional indexing question

13 Oct 2016 by Super Lloyd

I am creating a table now which contains truck information overtime, my question, what I want is two fold:1. write the query that get the latest record for each truck (I am creating the table right now, I have no date, difficult to test)2. make sure I create the right index that will...

entity-framework

How to check if a value exists in any key in PHP array

3 Mar 2017 by User1454

Hello All, I have an array of around 20 key items with 13 value in each key. I need to search specific value in all the keys if exists and if it exists I need the key index of that value.For e.g. I have Array( [0] => Array ( [0] => abc [1]...

Non clustered indexing does not reflect in the query performance

23 Mar 2017 by Member 1097736

I have a table which logs the user logins and the application from which user has logged.| S.No | UserID | Application | DateTime |-------------------------------------------This table has more than 1 million records.I am querying the list of records using LINQ based on list of...

Which DSS indexing technique is better to use?

30 Jul 2017 by OriginalGriff

Quote: Please, justify your answer with very well defined and sound reasoning. No. We do not do your homework: it is set for a reason. It is there so that you think about what you have been told, and try to understand it. It is also there so that your tutor can identify areas where you are...

Which DSS indexing technique is better to use?

1 Aug 2017 by Member 13339590

Dear Kashif check your handout (ch 26 & 27). Hope you'll get your answer from there.

I want to change combobox item text on checkbox checked

26 Oct 2017 by Member 9983063

Hello, Guys, I am facing an issue and issue is I have 9 checkboxes and 9 combo box item in combo box I want if I checked checkbox1 so combo box item 1 text = checkbox1 text please see the screenshot screenshot1 — imgbb.com[^] thanks in advance What I have tried: if(checkBox1.Checked == true) ...

I want to change combobox item text on checkbox checked

26 Oct 2017 by Ralf Meier

If I understood it right you should change your code like this :if(checkBox1.Checked == true) { comboBox1.Items(0) = "saturday"; } 'SelectedItem' will work too - but only if you have allready select an Item. Also you should make sure that each Item you want to use is existing ...

Tower of hanoi, index error

30 Oct 2017 by Member 13494159

i'm doing the famous game "Tower of Hanoi" and i have an error when i run my code. So, when i run it raise an IndexError: list index out of range, in line 17, which is " if new_disk

Tower of hanoi, index error

30 Oct 2017 by Patrice T

Quote: but i don't know what's the problem in my case. Use the debugger to see what your code is doing and inspect variables at point of failure. There is a tool that allow you to see what your code is doing, its name is debugger. It is also a great learning tool because it show you reality...

Invalid index when passing parameter to crystal report in VB.NET

28 Mar 2018 by Member 13749262

I am building a Windows forms solution in VS2017 using VB.net. The back-end is a Access 2010 DB which resides on a file server for now, but will be deployed elsewhere eventually. I am trying to run a report passing multiple parameters dynamically. I am trying to do this one parameter at at time...

Two index of a table can be activated at the same time

26 Apr 2018 by Rene Bustos

Hi People. I wondering if i have a TABLE with two INDEX. first one DataType Int, second one DataType DateTime if i must to do a query that seeks results with ColumnTypeInt AND ColumnTypeDateTime The indexs could be Activated? or what Happend in this case? SELECT * FROM Table WHERE...

How do I create elastic alias dynamically?

17 May 2018 by SumitBhavsar

I have tried Index Aliases | Elasticsearch Reference [2.0] | Elastic[^], but what if i need to create alias at time when documents are added into index based on values passed to insert. here in my case that value is customer type, so i want to create an alias which will be added into...