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  • LINQtoSQL Custom Constructor off Partial Class?

    - by sah302
    Hi all, I read this question here: http://stackoverflow.com/questions/82409/is-there-a-way-to-override-the-empty-constructor-in-a-class-generated-by-linqtosq Typically my constructor would look like: public User(String username, String password, String email, DateTime birthday, Char gender) { this.Id = Guid.NewGuid(); this.DateCreated = this.DateModified = DateTime.Now; this.Username = username; this.Password = password; this.Email = email; this.Birthday = birthday; this.Gender = gender; } However, as read in that question, you want to use partial method OnCreated() instead to assign values and not overwrite the default constructor. Okay so I got this : partial void OnCreated() { this.Id = Guid.NewGuid(); this.DateCreated = this.DateModified = DateTime.Now; this.Username = username; this.Password = password; this.Email = email; this.Birthday = birthday; this.Gender = gender; } However, this gives me two errors: Partial Methods must be declared private. Partial Methods must have empty method bodies. Alright I change it to Private Sub OnCreated() to remove both of those errors. However I am still stuck with...how can I pass it values as I would with a normal custom constructor? Also I am doing this in VB (converted it since I know most know/prefer C#), so would that have an affect on this?

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  • How to debug issues with differing execution times in different contexts.

    - by Dave
    The following question seems to be haunting me more consistently than most other questions recently. What kinds of things would you suggest I suggest that they look for when trying to debug "performance issues" like this? ok, get this - running this in query analyzer takes < 1 second exec usp_MyAccount_Allowance_Activity '1/1/1900', null, 187128 debugging locally, this takes 10 seconds: DataSet allowanceBalance = SqlHelper.ExecuteDataset( WebApplication.SQLConn(), CommandType.StoredProcedure, "usp_MyAccount_Allowance_Activity", Params); same parameters

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  • Conversion failed: SqlParameter and DateTime

    - by Tim
    I'm changing old,vulnerable sqlcommands with SqlParameters but get a SqlException: System.Data.SqlClient.SqlException {"Conversion failed when converting datetime from character string."} on sqlCommand.ExecuteScalar() Dim sqlString As String = _ "SELECT TOP 1 " & _ "fiSL " & _ "FROM " & _ "tabData AS D " & _ "WHERE " & _ "D.SSN_Number = '@SSN_Number' " & _ "AND D.fiProductType = 1 " & _ "AND D.Repair_Completion_Date > '@Repair_Completion_Date' " & _ "ORDER BY " & _ "D.Repair_Completion_Date ASC" Dim obj As Object Dim sqlCommand As SqlCommand Try sqlCommand = New SqlCommand(sqlString, Common.MyDB.SqlConn_RM2) sqlCommand.CommandTimeout = 120 sqlCommand.Parameters.AddWithValue("@SSN_Number", myClaim.SSNNumber) sqlCommand.Parameters.AddWithValue("@Repair_Completion_Date", myClaim.RepairCompletionDate) If Common.MyDB.SqlConn_RM2.State <> System.Data.ConnectionState.Open Then Common.MyDB.SqlConn_RM2.Open() obj = sqlCommand.ExecuteScalar() Catch ex As Exception Dim debug As String = ex.ToString Finally Common.MyDB.SqlConn_RM2.Close() End Try myClaim.RepairCompletionDate is a SQLDateTime. Do i have to remove the quotes in the sqlString to compare Date columns? But then i dont get a exception but incorrect results.

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  • How to designing a generic databse whos layout may change over time?

    - by mawg
    Here's a tricky one - how do I programatically create and interrogate a database who's contents I can't really foresee? I am implementing a generic input form system. The user can create PHP forms with a WYSIWYG layout and use them for any purpose he wishes. He can also query the input. So, we have three stages: a form is designed and generated. This is a one-off procedure, although the form can be edited later. This designs the database. someone or several people make use of the form - say for daily sales reports, stock keeping, payroll, etc. Their input to the forms is written to the database. others, maybe management, can query the database and generate reports. Since these forms are generic, I can't predict the database structure - other than to say that it will reflect HTML form fields and consist of a the data input from collection of edit boxes, memos, radio buttons and the like. Questions and remarks: A) how can I best structure the database, in terms of tables and columns? What about primary keys? My first thought was to use the control name to identify each column, then I realized that the user can edit the form and rename, so that maybe "name" becomes "employee" or "wages" becomes ":salary". I am leaning towards a unique number for each. B) how best to key the rows? I was thinking of a timestamp to allow me to query and a column for the row Id from A) C) I have to handle column rename/insert/delete. Foe deletion, I am unsure whether to delete the data from the database. Even if the user is not inputting it from the form any more he may wish to query what was previously entered. Or there may be some legal requirements to retain the data. Any gotchas in column rename/insert/delete? D) For the querying, I can have my PHP interrogate the database to get column names and generate a form with a list where each entry has a database column name, a checkbox to say if it should be used in the query and, based on column type, some selection criteria. That ought to be enough to build searches like "position = 'senior salesman' and salary 50k". E) I probably have to generate some fancy charts - graphs, histograms, pie charts, etc for query results of numerical data over time. I need to find some good FOSS PHP for this. F) What else have I forgotten? This all seems very tricky to me, but I am database n00b - maybe it is simple to you gurus?

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  • ORA-30036: unable to extend segment by 8 in undo tablespace 'UNDO'

    - by Nitin Gurram
    I am trying to update the table which has millions of records. However my update query will update around 2-3 millions of records. I am facing below error on executing the update query. I googled and found that I need to update the Table Space as DBA But is there any work around for executing the update without actually extending the UNDO table space or something dba is not required UPDATESERVICE SET CREATION_TIME = LAST_UPDATE_TIME WHERE CREATION_TIME is null

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  • postgresql: Fast way to update the latest inserted row

    - by Anonymous
    What is the best way to modify the latest added row without using a temporary table. E.g. the table structure is id | text | date My current approach would be an insert with the postgresql specific command "returning id" so that I can update the table afterwards with update myTable set date='2013-11-11' where id = lastRow However I have the feeling that postgresql is not simply using the last row but is iterating through millions of entries until "id = lastRow" is found. How can i directly access the last added row?

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  • Query to find all the nodes that are two steps away from a particular node.

    - by iecut
    Suppose I have two columns in a table that represents a graph, the first column is a FROMNODE and second one is TONODE. What I would like to know is that how will we find all the nodes that are two steps away from a particular node. Lets suppose I have a node numbered '1' and i would like to know all the nodes that are two steps away from it. I have tried(I am assuming the table name as graph) SELECT FROMNODE FROM GRAPH WHERE TONODE=1 (this is to select all the nodes that are connected to node 1, but I couldn't figure out how would I find all the nodes that are two steps away from node 1??)

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  • Can't return a List from a Compiled Query.

    - by Andrew
    I was speeding up my app by using compiled queries for queries which were getting hit over and over. I tried to implement it like this: Function Select(ByVal fk_id As Integer) As List(SomeEntity) Using db As New DataContext() db.ObjectTrackingEnabled = False Return CompiledSelect(db, fk_id) End Using End Function Shared CompiledSelect As Func(Of DataContext, Integer, List(Of SomeEntity)) = _ CompiledQuery.Compile(Function(db As DataContext, fk_id As Integer) _ (From u In db.SomeEntities _ Where u.SomeLinkedEntity.ID = fk_id _ Select u).ToList()) This did not work and I got this error message: Type : System.ArgumentNullException, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 Message : Value cannot be null. Parameter name: value However, when I changed my compiled query to return IQueryable instead of List like so: Function Select(ByVal fk_id As Integer) As List(SomeEntity) Using db As New DataContext() db.ObjectTrackingEnabled = False Return CompiledSelect(db, fk_id).ToList() End Using End Function Shared CompiledSelect As Func(Of DataContext, Integer, IQueryable(Of SomeEntity)) = _ CompiledQuery.Compile(Function(db As DataContext, fk_id As Integer) _ From u In db.SomeEntities _ Where u.SomeLinkedEntity.ID = fk_id _ Select u) It worked fine. Can anyone shed any light as to why this is? BTW, compiled queries rock! They sped up my app by a factor of 2.

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  • MySQL query advice

    - by vasion
    I am lost in MySQL documentation. I have a table with votes - it has these columns id song_id user_id created I cannot find the query which will process the information and output the 10 most voted songs in a given time period. What is it?

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  • named_scope or find_by_sql?

    - by keruilin
    I have three models: User Award Trophy The associations are: User has many awards Trophy has many awards Award belongs to user Award belongs to trophy User has many trophies through awards Therefore, user_id is a fk in awards, and trophy_id is a fk in awards. In the Trophy model, which is an STI model, there's a trophy_type column. I want to return a list of users who have been awarded a specific trophy -- (trophy_type = 'GoldTrophy'). Users can be awarded the same trophy more than once. (I don't want distinct results.) Can I use a named_scope? How about chaining them? Or do I need to use find_by_sql? Either way, how would I code it?

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  • MySQL foreign key creation with alter table command

    - by user313338
    I created some tables using MySQL Workbench, and then did forward ‘forward engineer’ to create scripts to create these tables. BUT, the scripts lead me to a number of problems. One of which involves the foreign keys. So I tried creating separate foreign key additions using alter table and I am still getting problems. The code is below (the set statements, drop/create statements I left in … though I don’t think they should matter for this): SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0; SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0; SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='TRADITIONAL'; DROP SCHEMA IF EXISTS `mydb` ; CREATE SCHEMA IF NOT EXISTS `mydb` DEFAULT CHARACTER SET latin1 COLLATE latin1_swedish_ci ; -- ----------------------------------------------------- -- Table `mydb`.`User` -- ----------------------------------------------------- DROP TABLE IF EXISTS `mydb`.`User` ; CREATE TABLE IF NOT EXISTS `mydb`.`User` ( `UserName` VARCHAR(35) NOT NULL , `Num_Accts` INT NOT NULL , `Password` VARCHAR(45) NULL , `Email` VARCHAR(45) NULL , `User_ID` INT NOT NULL AUTO_INCREMENT , PRIMARY KEY (`User_ID`) ) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `mydb`.`User_Space` -- ----------------------------------------------------- DROP TABLE IF EXISTS `mydb`.`User_Space` ; CREATE TABLE IF NOT EXISTS `mydb`.`User_Space` ( `User_UserName` VARCHAR(35) NOT NULL , `User_Space_ID` INT NOT NULL AUTO_INCREMENT , PRIMARY KEY (`User_Space_ID`), FOREIGN KEY (`User_UserName`) REFERENCES `mydb`.`User` (`UserName`) ON UPDATE CASCADE ON DELETE CASCADE) ENGINE = InnoDB; SET SQL_MODE=@OLD_SQL_MODE; SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS; SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS; The error this produces is: Error Code: 1005 Can't create table 'mydb.user_space' (errno: 150) Anybody know what the heck I’m doing wrong?? And anybody else have problems with the script generation done by mysql workbench? It’s a nice tool, but annoying that it pumps out scripts that don’t work for me. [As an fyi here’s the script it auto-generates: SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0; SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0; SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='TRADITIONAL'; DROP SCHEMA IF EXISTS `mydb` ; CREATE SCHEMA IF NOT EXISTS `mydb` DEFAULT CHARACTER SET latin1 COLLATE latin1_swedish_ci ; -- ----------------------------------------------------- -- Table `mydb`.`User` -- ----------------------------------------------------- DROP TABLE IF EXISTS `mydb`.`User` ; CREATE TABLE IF NOT EXISTS `mydb`.`User` ( `UserName` VARCHAR(35) NOT NULL , `Num_Accts` INT NOT NULL , `Password` VARCHAR(45) NULL , `Email` VARCHAR(45) NULL , `User_ID` INT NOT NULL AUTO_INCREMENT , PRIMARY KEY (`User_ID`) ) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `mydb`.`User_Space` -- ----------------------------------------------------- DROP TABLE IF EXISTS `mydb`.`User_Space` ; CREATE TABLE IF NOT EXISTS `mydb`.`User_Space` ( `User_Space_ID` INT NOT NULL AUTO_INCREMENT , PRIMARY KEY (`User_Space_ID`) , INDEX `User_ID` () , CONSTRAINT `User_ID` FOREIGN KEY () REFERENCES `mydb`.`User` () ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; SET SQL_MODE=@OLD_SQL_MODE; SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS; SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS; ** Thanks!]

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  • Best way to store sales tax information

    - by Seph
    When designing a stock management database system (sales / purchases) what would be the best way to store the various taxes and other such amounts? A few of the fields that could be saved are: Unit price excluding tax Unit price including tax Tax per item Total excluding tax (rounded to 2 decimals) Total including tax (rounded to 2 decimals) Total tax (rounded to 2 decimals) Currently the most reasonable solution so far is storing down (roughly) item, quantity, total excluding tax (rounded) and the total tax (rounded). Can anyone suggest some better way of storing this details for a generic system? Also, given the system needs to be robust, what should be done if there were multiple tax values (eg: state and city) which might need to be separated, in this case a separate table would be in order, but would it be considered excessive to just have a rowID and some taxID mapping to a totalTax column?

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  • TooManyRowsAffectedException with encrypted triggers

    - by Jon Masters
    I'm using nHibernate to update 2 columns in a table that has 3 encrypted triggers on it. The triggers are not owned by me and I can not make changes to them, so unfortunately I can't SET NOCOUNT ON inside of them. Is there another way to get around the TooManyRowsAffectedException that is thrown on commit? Update 1 So far only way I've gotten around the issue is to step around the .Save routine with var query = session.CreateSQLQuery("update Orders set Notes = :Notes, Status = :Status where OrderId = :Order"); query.SetString("Notes", orderHeader.Notes); query.SetString("Status", orderHeader.OrderStatus); query.SetInt32("Order", orderHeader.OrderHeaderId); query.ExecuteUpdate(); It feels dirty and is not easily to extend, but it doesn't crater.

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  • why this left join query failed to load all the data in left table ?

    - by lzyy
    users table +-----+-----------+ | id | username | +-----+-----------+ | 1 | tom | | 2 | jelly | | 3 | foo | | 4 | bar | +-----+-----------+ groups table +----+---------+-----------------------------+ | id | user_id | title | +----+---------+-----------------------------+ | 2 | 1 | title 1 | | 4 | 1 | title 2 | +----+---------+-----------------------------+ the query SELECT users.username,users.id,count(groups.title) as group_count FROM users LEFT JOIN groups ON users.id = groups.user_id result +----------+----+-------------+ | username | id | group_count | +----------+----+-------------+ | tom | 1 | 2 | +----------+----+-------------+ where is the rest users' info? the result is the same as inner join , shouldn't left join return all left table's data? PS:I'm using mysql

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  • How to switch from MSSQL to MySQL for using with Excel pivot

    - by Sim
    Hi all, I have a table that contains sales transaction (~20 mil rows). Previously I used MSSQL and export it to an Excel pivot. Data refresh took 10-15 minutes but still do-able. However, after I migrated to MySQL (using XamppLite & ODBC), it took forever to refresh the data in the Excel pivot. Maybe I didn't optimize the MySQL good enough ? Anyone can share some thoughts 'bout this ? Thanks

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  • How Can I truncate Multiple Tables in MySql?

    - by Luiscencio
    I need to clear all my inventory tables. I've tryed SELECT 'TRUNCATE TABLE ' + TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME LIKE 'inventory%' but I get this error: Truncated incorrect DOUBLE value: 'TRUNCATE TABLE ' Error Code 1292 if this is the correct way, then what am I doing wrong?

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  • Split function in where clause

    - by abhishek-khandelwal
    hello friends I am using following query in linq In product table following type of data are stored abc-def bcd=fgh abc-xyz var query=from prod in db.Product join cat in db.category on prod.categoryId=cat.categoryID where prod.productName.split('-')[0]=="abc" but in that query it product annoumous problem Please give some suggestion to split in where caluse

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  • Transactional isolation level needed for safely incrementing ids

    - by Knut Arne Vedaa
    I'm writing a small piece of software that is to insert records into a database used by a commercial application. The unique primary keys (ids) in the relevant table(s) are sequential, but does not seem to be set to "auto increment". Thus, I assume, I will have to find the largest id, increment it and use that value for the record I'm inserting. In pseudo-code for brevity: id = select max(id) from some_table id++ insert into some_table values(id, othervalues...) Now, if another thread started the same transaction before the first one finished its insert, you would get two identical ids and a failure when trying to insert the last one. You could check for that failure and retry, but a simpler solution might be setting an isolation level on the transaction. For this, would I need SERIALIZABLE or a lower level? Additionally, is this, generally, a sound way of solving the problem? Are the any other ways of doing it?

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  • Calling sp and Performance strategy.

    - by Costa
    Hi I find my self in a situation where I have to choose between either creating a new sp in database and create the middle layer code. so loose some precious development time. also the procedure is likely to contain some joins. Or use two existing sp(s), the problem of this approach is that I am doing two round trips to database. which can be poor performance especially if I have database in another server. Which approach you will go?, and why? thanks

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  • Error: The conversion of a nvarchar data type to a datetime data type resulted in an out-of-range value

    - by CPM
    I know that there are simmilar questions like this on the forum, however I am still having problems to update a datetime field o the database. I dont get any problems when inserting but I get problems when updating and I am formating the same way , like this: e.Values.Item("SelectionStartDate") = Format(startdate, "yyyy-MM-dd") + " " + startTime1 + ".000" startTime is of type string. I have tried different solution that I came across on the internet but still get this error. Please help. Thanks in advance

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  • Where Not In OR Except simulation of SQL in LINQ to Objects

    - by Thinking
    Suppose I have two lists that holds the list of source file names and destination file names respectively. The Sourcefilenamelist has files as 1.txt, 2.txt,3.txt, 4.txt while the Destinaitonlist has 1.txt,2.txt. I ned to write a linq query to find out which files are in SourceList that are absent in DestinationFile list. e.g. here the out put will be 3.txt and 4.txt. I have done this by a foreach statement. but now I want to do the same by using LINQ(C#). Edit: My Code is List<FileList> sourceFileNames = new List<FileList>(); sourceFileNames.Add(new FileList { fileNames = "1.txt" }); sourceFileNames.Add(new FileList { fileNames = "2.txt" }); sourceFileNames.Add(new FileList { fileNames = "3.txt" }); sourceFileNames.Add(new FileList { fileNames = "4.txt" }); List<FileList> destinationFileNames = new List<FileList>(); destinationFileNames.Add(new FileList { fileNames = "1.txt" }); destinationFileNames.Add(new FileList { fileNames = "2.txt" }); IEnumerable<FileList> except = sourceFileNames.Except(destinationFileNames); And Filelist is a simple class with only one property fileNames of type string.

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  • Check if access table exists

    - by HasanGursoy
    I want to log web site visits' IP, datetime, client and refferer data to access database but I'm planning to log every days log data in separate tables in example logs for 06.06.2010 will be logged in 2010_06_06 named table. When date is changed I'll create a table named 2010_06_07. But the problem is if this table is already created. Any suggestions how to check if table exists in Access?

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  • When is referential integrity not appropriate?

    - by Curtis Inderwiesche
    I understand the need to have referential integrity for limiting specific values on entry or possibly preventing them from removal upon a request of deletion. However, I am unclear as to a valid use case which would exclude this mechanism from always being used. I guess this would fall into several sub-questions: When is referential integrity not appropriate? Is it appropriate to have fields containing multiple and/or possibly incomplete subsets of a foreign key's list? Typically, should this be a schema structure design decision or an interface design decision? (Or possibly neither or both) Thoughts?

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  • MySQL slow query

    - by andrhamm
    SELECT items.item_id, items.category_id, items.title, items.description, items.quality, items.type, items.status, items.price, items.posted, items.modified, zip_code.state_prefix, zip_code.city, books.isbn13, books.isbn10, books.authors, books.publisher FROM ( ( items LEFT JOIN bookitems ON items.item_id = bookitems.item_id ) LEFT JOIN books ON books.isbn13 = bookitems.isbn13 ) LEFT JOIN zip_code ON zip_code.zip_code = items.item_zip WHERE items.rid = $rid` I am running this query to get the list of a user's items and their location. The zip_code table has over 40k records and this might be the issue. It currently takes up to 15 seconds to return a list of about 20 items! What can I do to make this query more efficient?

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  • Insert rownumber repeatedly in records in t-sql.

    - by jeff
    Hi, I want to insert a row number in a records like counting rows in a specific number of range. example output: RowNumber ID Name 1 20 a 2 21 b 3 22 c 1 23 d 2 24 e 3 25 f 1 26 g 2 27 h 3 28 i 1 29 j 2 30 k I rather to try using the rownumber() over (partition by order by column name) but my real records are not containing columns that will count into 1-3 rownumber. I already try to loop each of record to insert a row count 1-3 but this loop affects the performance of the query. The query will use for the RDL report, that is why as much as possible the performance of the query must be good. any suggestions are welcome. Thanks

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