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  • How to run a loop of queries in access?

    - by tksy
    Hi I have a database with a table which is full of conditions and error messages for checking another database. I want to run a loop such that each of these conditions is checked against all the tables in the second database and generae a report which gives the errors. Is this possible in ms access. For example, querycrit table id query error 1 speed<25 and speed>56 speed above limit 2 dist<56 or dist >78 dist within limit I have more than 400 queries like this of different variables. THe table against which I am running the queries is records table id speed dist accce decele aaa bbb ccc 1 33 34 44 33 33 33 33 2 45 44 55 55 55 22 23 regards ttk

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  • How to calculate the sum of a column in an MS Access table for a given date (a single day, month or year)

    - by cMinor
    I have a table in Access in a custom format saved as dd/MM/yyyy hh:mm:ss tt , Also A form in VB.NET 2010, I get a specific day, month and year with no problem but the problem comes when I want to query the sum of a column named value depending on a specific month or day or year.... The table is like: +-----+-----------+-------------------------+ | id | value | date | +-----+-----------+-------------------------+ | id1 | 1499 | 01/01/2012 07:30:11 p.m.| | id2 | 1509 | 11/02/2012 07:30:11 p.m.| | id3 | 1611 | 21/10/2012 07:30:11 p.m.| | id1 | 1115 | 11/10/2012 07:30:11 p.m.| | id1 | 1499 | 17/05/2012 07:30:11 p.m.| | id2 | 1709 | 11/06/2012 07:30:11 p.m.| | id3 | 1911 | 30/07/2012 07:30:11 p.m.| | id1 | 1015 | 01/08/2012 07:30:11 p.m.| | id1 | 1000 | 11/05/2012 07:30:11 p.m.| |+-----+-----------+------------------------+ So I Know the query SELECT SUM(value) FROM mytable WHERE date in='01/05/2012 00:00:00' ... How to tell the query I want the month of May so I would get 1499+1000= 2499 Or how to tell I want the year 2012 so I would get the sum of all the table Which would be the correct syntax...

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  • Linq to NHibernate, Order by Rand() ?

    - by Felipe
    Hi everybody, I'm using Linq To Nhibernate, and with a HQL statement I can do something like this: string hql = "from Entity e order by rand()"; Andi t will be ordered so random, and I'd link to know How can I do the same statement with Linq to Nhibernate ? I try this: var result = from e in Session.Linq<Entity> orderby new Random().Next(0,100) select e; but it throws a exception and doesn't work... is there any other way or solution? Thanks Cheers

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  • How to use a c# datagridview to update a database file just like Access does?

    - by mackeyka
    I have googled everywhere and I am finally giving up and asking here. I am working in Visual Studio 2010 with C#. I have set up a form with a datagridview connected to a MSSQL database and I need to save changes made in the datagridview back to the physical database. I am having some success but I think that I am going about some of it completely wrong because I can not get it to save consistently. What I really want is for the updates to work just like they do when working with Access. When I edit a row in the datagridview and then leave that row, either by selecting another row or by selecting some other control on the form or even by changing to another form or quitting the application the row should be automatically pdated to the physical database. The first part of this question I think is, what is the proper event to use to trigger the save and then second what methods should be used to actually write the data to the database?

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  • How to increment counters based on a printed array

    - by Sam Liew
    I managed to developed a simple board of 5x5 using random numbers and array. Big achievement for someone like me! :) Now I have to increment the counters depending on the frequency of the numbers. If the value within 0-49 is printed..then nCounter++ If the value within 50-75 is printed..then pCounter++ something like that. The problem is that I don't know how to increase the counters based on the printed board. Here is the code: #include <stdio.h> #include <stdlib.h> #include <time.h> int main() { //Initialize Variables int randomNumber; int rows; int columns; int hdCounter =0; int hCounter = 0; int cCounter = 0; int pCounter = 0; int nCounter = 0; //Declare board size int board[5][5]; //size of board is 5 x 5 //Create the random number generator seed srand(time(NULL)); //Assign the random numbers from 1 - 25 into variable randomNumber //Create the rows for the board for ( rows = 1; rows <= 5 ; rows++ ) { //Create the colimns for the board for ( columns = 1; columns <= 5 ; columns++ ) { //Assign variable randomNumber into variable board randomNumber = rand() %100 + 1; board[rows][columns] = randomNumber; //print the board printf("%d\t", board[rows][columns]); //calculate the frequency of numbers on the printed board if (randomNumber >= 85 && randomNumber <= 100 ) hdCounter++; else if ( randomNumber >= 75 ) hCounter++; else if ( randomNumber >= 65 ) cCounter++; else if ( randomNumber >= 50 ) pCounter++; else if ( randomNumber >= 1 ) nCounter++; else continue; } //Newline after the end of 5th column. printf("\n\n"); } printf( "N \t P \t C \t H \t HD\n\n" ); printf("%d \t %d \t %d \t %d \t %d \t", nCounter, pCounter, cCounter, hCounter, hdCounter); }//end main I tried replacing randomNumber in the if-statement with board[rows][columns] but I seem to get the same undesired results.

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  • How to programmatically change a data cell of Ms Access using VB.Net?

    - by manuel
    I have a Microsoft Access database file connected to VB.NET. In the database table, I have a 'No.' and a 'Status' column. Then I have a textbox where I can input an integer. I also have a button, which will change the data cell in 'Status' where 'No.' = textbox.Text(), when I click it. Let's say I want the 'Status' cell to be changed to "Low". What codes should I put in the button_Click event handler? Here is the codes I used to retrieve and display the database table. Public Class theForm Dim con As New OleDb.OleDbConnection Dim ds As New DataSet Dim daTitles As OleDb.OleDbDataAdapter Private Sub theForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=|DataDirectory|\db1.mdb" con.Open() daTitles = New OleDb.OleDbDataAdapter("SELECT * FROM Titles", con) daTitles.Fill(ds, "Titles") DataGridView1.DataSource = ds.Tables("Titles") DataGridView1.AutoResizeColumns() End Sub

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  • MS Access Mark Duplicates in order of appearance - using the function RankOfDup: (SELECT Count(*) ...)

    - by veska stoyanova
    I'm trying to create Ranking that shows the sequence of agreements for the two fields Customers and Agreements. The number for agreements must be unique, whereas customers can repeat. The formula RankOfDup: (SELECT Count(*) FROM Data a WHERE a.customer=Data.customer And a.agreement >= Data.agreement) Works beautifully but after this query with columns Agreement, Customer and RankofDup, I need to create crosstab that transposes the RankofDub. It works when I make the table first and then create query but my data is too large so I'm trying to put the select query with the ranking in a crosstab query. However, when I try to do this Access gives error message that microsoft jet ... doesn't recognise Data.customer? Any ideas how I can fix this?

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  • How to get unique numbers using randomint python?

    - by user2519572
    I am creating a 'Euromillions Lottery generator' just for fun and I keep getting the same numbers printing out. How can I make it so that I get random numbers and never get the same number popping up: from random import randint numbers = randint(1,50) stars = randint(1,11) print "Your lucky numbers are: ", numbers, numbers, numbers, numbers, numbers print "Your lucky stars are: " , stars, stars The output is just: >>> Your lucky numbers are: 41 41 41 41 41 >>> Your lucky stars are: 8 8 >>> Good bye! How can I fix this? Regards

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  • Characteristics of an Initialization Vector

    - by Jamie Chapman
    I'm by no means a cryptography expert, I have been reading a few questions around Stack Overflow and on Wikipedia but nothing is really 'clear cut' in terms of defining an IV and it's usage. Points I have discovered: An IV is pre-pended to a plaintext message in order to strengthen the encryption The IV is truely random Each message has it's own unique IV Timestamps and cryptographic hashes are sometimes used instead of random values, but these are considered to be insecure as timestamps can be predicted One of the weaknesses of WEP (in 802.11) is the fact that the IV will reset after a specific amount of encryptions, thus repeating the IV I'm sure there are many other points to be made, what have I missed? (or misread!)

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  • What are alternatives to standard ORM in a data access layer?

    - by swampsjohn
    We're all familiar with basic ORM with relational databases: an object corresponds to a row and an attribute in that object to a column (or some slight variation), though many ORMs add a lot of bells and whistles. I'm wondering what other alternatives there are (besides raw access to the database or whatever you're working with). Alternatives that just work with relational databases would be great, but ones that could encapsulate multiple types of backends besides just SQL (such as flat files, RSS, NoSQL, etc.) would be even better. I'm more interested in ideas rather than specific implantations and what languages/platforms they work with, but please link to anything you think is interesting.

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  • Choose item from a list with bias?

    - by ooboo
    Given a list of items x1 ... xn and associated probabilties p1 ... pn that sum up to 1 there's a well known procedure to select a random item with its associated proabability by sorting the list according to weight, choosing a random value between 1 and 0, and adding up to a culmination sum until it exceeds the value selected and return the item at this point. So if we have x1 - 0.5, x2 - 0.3, x3 - 0.2, if the randomly chosen value is less than 0.5 x1 will be chosen, if between 0.5 and 0.8, x2, and else x3. This requires sorting so it needs O(nlogn) time. Is there anything more efficient than that?

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  • MS Access - Keeping track (transacation) of all activity while form is open...

    - by Ron Mac
    Hi and thanks for reading. I am not a database/vba guy and my experience is strictly in the JAVA world. However, I need to have an ACCESS form open. While it is open and new data is entered into it (via the underlying query OR any other data changes in other tables based on sql updates attached to buttons on this form), is there a way that I can initiate a transaction so that at the bottom of the form I could have a button that says "Exit and committ changes" or "Cancel and Rollback changes". I guess I thought of a situation where I could do something like: On Form OPEN, START TRANSACTION On "CLICK OK", COMMIT TRANSACTION or ON "CLICK CANCEL" ROLLBACK. I'm aware how to do the Workspace.BeginTransaction but I'm not sure if that will apply if I do it on FORM OPEN and then on FORM CLOSE do the COMMIT/ROLLBACK locgin? Any insight would be great.

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  • What is a good way of checking to see if a particular user may access a particular file?

    - by Rising Star
    I am working on application which runs as a special unprivileged user. I would like to be able to easily check to see if the user can read a given file. It seems like this should be easy, even when I go into the file in Windows Explorer and see that the read permission is checked, it sometimes seems that there is still something preventing the user from reading the file (such as a parent directory that the user cannot browse) when I try to read it as the user programmatically. The user has no console logon permission, so I can't just log in as the user and try to read the file. So... If I want to know, "Does UserBob have access to file c:\specialPath\specialFile, what is an easy way to find out? BTW, my environment is Windows Server 2003.

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  • How are a session identifiers generated?

    - by Asaf R
    Most web applications depend on some kind of session with the user (for instance, to retain login status). The session id is kept as a cookie in the user's browser and sent with every request. To make it hard to guess the next user's session these session-ids need to be sparse and somewhat random. The also have to be unique. The question is - how to efficiently generate session ids that are sparse and unique? This question has a good answer for unique random numbers, but it seems not scalable for a large range of numbers, simply because the array will end up taking a lot of memory.

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  • Mean of Sampleset and powered Sampleset

    - by Milla Well
    I am working on an ICA implementation wich is based on the assumption, that all source signals are independent. So I checked on the basic concepts of Dependence vs. Correlation and tried to show this example on sample data from numpy import * from numpy.random import * k = 1000 s = 10000 mn = 0 mnPow = 0 for i in arange(1,k): a = randn(s) a = a-mean(a) mn = mn + mean(a) mnPow = mnPow + mean(a**3) print "Mean X: ", mn/k print "Mean X^3: ", mnPow/k But I couldn't produce the last step of this example E(X^3) = 0: >> Mean X: -1.11174580826e-18 >> Mean X^3: -0.00125229267144 First value I would consider to be zero, but second value is too large, isn't it? Since I subtract the mean of a, I expected the mean of a^3 to be zero as well. Does the problem lie in the random number generator, the precision of the numerical values in my misunderstanding of the concepts of mean and expected value?

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  • Are there issues with tables using an autonumber as a primary key in a back-end ms access db?

    - by owlie
    I inherited an MS Access database at my office that is heavily used by several people over the network. This causes many issues with data collisions and locks. I want to split the db so that each user has thier own front-end app and maintain the core data on the server. Several of the tables use an autonumber:sequence:long as thier primary key - in researching how to perform the split I've come across several posts that hint this can cause issues when distributing a database but I haven't been able to find anything solid. The issue seems to be that a user can begin a new record and receive the next autonumber but a second user can create a new record within a short interval and receive the same autonumber resulting in an error? Does Jet handle this correctly or are there autonumber issues with a FE/BE database? If it's an unlikely-but-possile occurance I'm sure it will still be much better than what my users are currently experiencing but I'd like to know if there are ways I can minimize such issues. Thanks for your help!

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  • Jet Database (ms access) ExecuteNonQuery - Can I make it faster?

    - by bluebill
    Hi all, I have this generic routine that I wrote that takes a list of sql strings and executes them against the database. Is there any way I can make this work faster? Typically it'll see maybe 200 inserts or deletes or updates at a time. Sometimes there is a mixture of updates, inserts and deletes. Would it be a good idea to separate the queries by type (i.e. group inserts together, then updates and then deletes)? I am running this against an ms access database and using vb.net 2005. Public Function ExecuteNonQuery(ByVal sql As List(Of String), ByVal dbConnection as String) As Integer If sql Is Nothing OrElse sql.Count = 0 Then Return 0 Dim recordCount As Integer = 0 Using connection As New OleDb.OleDbConnection(dbConnection) connection.Open() Dim transaction As OleDb.OleDbTransaction = connection.BeginTransaction() 'Using cmd As New OleDb.OleDbCommand() Using cmd As OleDb.OleDbCommand = connection.CreateCommand cmd.Connection = connection cmd.Transaction = transaction For Each s As String In sql If Not String.IsNullOrEmpty(s) Then cmd.CommandText = s recordCount += cmd.ExecuteNonQuery() End If Next transaction.Commit() End Using End Using Return recordCount End Function

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  • How to get some randomized concats based on 2 columns from 1 table?

    - by Nils Riedemann
    Hey folks, i have a large user Database (13k+), and for some reason i need to create random names. The users table has "first_name" and "last_name". Now i want to have 10 concats of full_name and last_name of two completely random rows. Is that even possible with SQL? My other idea was just to create a full_names and last_names table … but that would'nt be as much challenging. Oh, and it should not take up too much performance :) (so order by rand() is not an option ;))

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  • Asp.net loading a file encounters "Access to the path … is denied" in development on Windows 7

    - by ray247
    Hi there, I have an Asp.net app that simply reads an xml file and this code used to work fine on Vista with VS2008, now I just moved to Windows 7 and I migrated the code to VS2010, I encoutered “Access to the path [path to my webapp folder] is denied". Nothing else is changed, I tried to change folder perms even though I didn't think it got anything to do with that since the same code used to work fine, but still didn't get around this problem. Could someone please shed some light on why this may be happening and how to fix it? Thanks, Ray.

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  • How many double numbers are there between 0.0 and 1.0?

    - by polygenelubricants
    This is something that's been on my mind for years, but I never took the time to ask before. Many (pseudo) random number generators generate a random number between 0.0 and 1.0. Mathematically there are infinite numbers in this range, but double is a floating point number, and therefore has a finite precision. So the questions are: Just how many double numbers are there between 0.0 and 1.0? Are there just as many numbers between 1 and 2? Between 100 and 101? Between 10^100 and 10^100+1? Note: if it makes a difference, I'm interested in Java's definition of double in particular.

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  • C++ function for picking from a list where each element has a distinct probability

    - by Stuart
    I have an array of structs and one of the fields in the struct is a float. I want to pick one of the structs where the probability of picking it is relative to the value of the float. ie struct s{ float probability; ... } sArray s[50]; What is the fastest way to decide which s to pick? Is there a function for this? If I knew the sum of all the probability fields (Note it will not be 1), then could I iterate through each s and compare probability/total_probability with a random number, changing the random number for each s? ie if( (float) (rand() / RAND_MAX) < probability)...

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  • python -> combinations of numbers and letters

    - by tekknolagi
    #!/usr/bin/python import random lower_a = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'] upper_a = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'] num = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'] all = [] all = " ".join("".join(lower_a) + "".join(upper_a) + "".join(num)) all = all.split() x = 1 c = 1 while x < 10: y = [] for i in range(c): a = random.choice(all) y.append(a) print "".join(y) x += 1 c += 1 what i have now outputs something like the following: 5 hE HAy 1kgy Pt6JM 2pFuCb Jv5osaX 5q8PwWAO SvHWRKfI5 how can i make it systematically go through every combination of letters (upper and lowercase) for a given length, then add 1 to that length and repeat the process?

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  • Trying to use tcl threads on windows 7 results in access violation.

    - by Juan
    I'm trying to get this simple program to work on windows, but it crashes: unsigned (__stdcall testfoo)(ClientData x) { return 0; } int main() { Tcl_ThreadId testid = 0; Tcl_CreateThread(&testid, testfoo, (ClientData) NULL, TCL_THREAD_STACK_DEFAULT, TCL_THREAD_NOFLAGS); } I am using a makefile generated by cmake and linking against a version of Tcl 8.5.7 I compiled myself using Visual C++ 2008 express. It was compiled using msvcrt,static,threads and the name of the resulting library is tcl85tsx.lib. The error is: Unhandled exception at 0x77448c39 in main.exe: 0xC0000005: Access violation writing location 0x00000014. The Tcl library works fine, and I can even run a threading script example by loading the Thread extension into it. My assumption is that there is something horribly wrong with a memory violation, but I have no idea what. Any help appreciated.

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