Search Results

Search found 11052 results on 443 pages for 'linked tables'.

Page 137/443 | < Previous Page | 133 134 135 136 137 138 139 140 141 142 143 144  | Next Page >

  • what is a performance way to 'tree-walking' through my Entity Framework data

    - by Greg
    Hi, I have a Entity Framework design with a few tables that define a "graph". So there can be a large chain of relationships between objects in the few tables via concept of parent/child relationships. What is a performance way to 'tree-walking' through my Entity Framework data? That is I assume I wouldn't want to load the full set of all NODES and RELATIONSHIPS from the database for the purpose of walking the tree, where the end result may only be identifying leaf nodes? Or would this be OK with the way lazy loading may work at the column/parameter level? Else how could I load just the skeleton of the objects and then when needing to refer to any attributes have them lazy load then?

    Read the article

  • Problem with auto increment primary key (MySQL).

    - by mathon12
    I have 2 tables each using other's primary key as a foreign key. The primary keys for both are set to auto_increment. The problem is, when I try to create and entry into one of the tables, I have no idea what the primary key of the entry is and can't figure out what to put in the other table as a foreign key. What should I do? Do I drop auto_increment altogether and cook up a unique identifier for each entry so I can use it to address the created entries? I'm using PHP, if that's relevant. Thanks.

    Read the article

  • jquery dropdownbox auto populated with mysql data

    - by Xin
    I've got 2 dropdownboxes. Dropdownbox 1 shows all the tables from a database. When dropdownbox 1 is selected; dropdownbox 2 will be populated with tablefields from the selected table. dropdownbox 1: This dropdown is populated with the following mysql query: "show tables from testdb" dropdownbox 2: This dropdown will auto populate when dropdownbox 1 is selected. Dropdownbox 2 will be populate with the following query: "describe tablename" //tablename selected from dropdownbox 1 I want to make this using jquery. Can anyone point me into the right direction?

    Read the article

  • How to implement multi relationship in SQL Server?

    - by Ethan
    I’m trying to design a database to use with ASP.net MVC application. Here is the scenario: There are three entities and users can post their comments for each of these different entities. I just wonder how just put one table for Comments and link all other entities to it. Obviously, Comments table needs 3 references (foreign key) to those tables but as you know these foreign keys can’t be null and just one of them can be filled for each row. Is there any better way than implementing three different tables for each entity’s comments?

    Read the article

  • MS SQL Server 2008 Stored Procedure Result as Column Default Value

    - by user337501
    First of all, thank you guys. You always know how to direct me when I cant even find the words to explain what the heck im trying to do. The default values of the columns on a couple of my tables need to equal the result of some complicated calculations on other columns in other tables. My first thought is to simply have the column default value equal the result of a stored procedure. I would also have one or more of the parameters pulled from the columns in the calling table. I don't know the syntax of how to do it though, and any time the word "stored" and "procedure" land next to each other in google I'm flooded with info on Parameter default values and nothing relating to what I actually want. Half of that was more of a vent than a question...any ideas though? And plz plz dont say "Well, you could use an On-Insert Trigger to..."

    Read the article

  • Oracle/c#: How do i use bind variables with select statements to return multiple records?

    - by twiga
    I have a question regarding Oracle bind variables and select statements. What I would like to achieve is do a select on a number different values for the primary key. I would like to pass these values via an array using bind values. select * from tb_customers where cust_id = :1 int[] cust_id = { 11, 23, 31, 44 , 51 }; I then bind a DataReader to get the values into a table. The problem is that the resulting table only contains a single record (for cust_id=51). Thus it seems that each statement is executed independently (as it should), but I would like the results to be available as a collective (single table). A workaround is to create a temporary table, insert all the values of cust_id and then do a join against tb_customers. The problem with this approach is that I would require temporary tables for every different type of primary key, as I would like to use this against a number of tables (some even have combined primary keys). Is there anything I am missing?

    Read the article

  • How to retrieve MYSQL records as an INSERT statement.

    - by Aglystas
    I'm trying come up with the best method of synchronizing particular rows of 2 different database tables. So, for example there's 2 product tables in different databases as such... Origin Database product{ merchant_id, product_id, ... additional fields } Destination Database product{ merchant_id product_id ... additional fields } So, the database schema is the same for both. However I'm looking to select records with a particular merchant_id, remove all records from the destination table that have that merchant_id and replace those records with records from the origin database of the same merchant_id. My first thought was using mysqldump, parsing out the create table statements, and only running the Insert Statements. Seems like a pain though. So I was wondering if there is a better technique to do this. I would think mysql has some method of creating INSERT statements as output from a SELECT statement, so you can define how to insert specific record information into a new db. Any help would be appreciated, thank you much.

    Read the article

  • which lightweight SQL Server type could I use on my Dev machine for a C# VS2010 project?

    - by Greg
    Hi, Which lightweight SQL Server type could I use on my Dev machine for a C# VS2010 project? (e.g. sql server express, sql server ce, full version etc). That is, I'm running on a VMWare fusion instance on my MacBook, and just want something to develop against for a C# VS2010 project. I'm planning on having a simple database (not many tables) but will use Entity Framework. I haven't used SQL Server before so a quick pointer re what is the best database admin interface/app to use for the version you recommend (e.g. to create database, tables etc).

    Read the article

  • Rails with DB2 and multiple schemas

    - by GNUMatrix
    I have a 'legacy' DB2 database that has many other applications and users. Trying to experiment with a rails app. Got everything working great with the ibm_db driver. Problem is that I have some tables like schema1.products, schema1.sales and other tables like schema2.employees and schema2.payroll. In the ibm_db adapter connection, I specify a schema, like schema1 or schema2, and I can work within that one schema, but I need to be able to easily (and transparently) reference both schemas basically interchangeably. I don't want to break the other apps, and the SQL I would normally write against DB2 doesn't have any of these restrictions (schemas can be mixed in SQL against DB2 without any trouble at all). I would like to just specify table names as "schema1.products" for example and be done with it, but that doesn't seem to jive with the "rails way" of going about it. Suggestions?

    Read the article

  • Keep local MS SQL 2008 DB table and remote SQL Azure DB table in sync

    - by Boomerangertanger
    Hi there, I have a dedicated server which hosts a Windows Service which does a lot of very heavy load stuff and populates a number of SQL Server database tables. However, of all the database tables it populates and works with, I want only one to be synchronised with a remote SQL Azure DB table. This is because this table holds what I called Resolved data, which is the end result of the Windows Service's work. I would like to keep a SQL Azure database table in sync with this database table. As far as I understand, my options are: Move everything onto Azure (but that involves a massive development overhead and risk) Have another Windows Service on the dedicated server which essentially looks at changed records since the last update and then manually update the SQL Azure table

    Read the article

  • Entity framework and database logic.

    - by Xavier Devian
    Hi all, i have a question that's being around for several years. As all you know entity framework is an ORM tool that tries to model the database to an object oriented access model. All the samples I've seen are quering directly to the database tables. So, which is the role of the views in the database now?. The views were used to model the database in a more friendly way, that is, several physical tables, one logic table. This was great for example in hidding the complex relational model on stored procedures as queryng the views inside them was much easier than reproducing the query joins over and over on each stored procedure. So the question is, why is entity framework so good if stored procedures can not take benefit of it?

    Read the article

  • What is the benefit of using int instead of bigint in this case?

    - by Yeti
    (MYSQL n00b) I have 3 tables: id = int(10), photo_id = bigint(20) PHOTO records limited to 3 million PHOTO: +-------+-----------------+ | id | photo_num | +-------+-----------------+ | 1 | 123456789123 | | 2 | 987654321987 | | 3 | 5432167894321 | +-------+-----------------+ COLOR: +-------+-----------------+---------+ | id | photo_num | color | +-------+-----------------+---------+ | 1 | 123456789123 | red | | 2 | 987654321987 | blue | | 3 | 5432167894321 | green | +-------+-----------------+---------+ SIZE: +-------+-----------------+---------+ | id | photo_num | size | +-------+-----------------+---------+ | 1 | 123456789123 | large | | 2 | 987654321987 | small | | 3 | 5432167894321 | medium | +-------+-----------------+---------+ Both COLOR and SIZE tables will have several million records. Q1: Is it better to change photo_num on COLOR and SIZE to int(10) and point it to PHOTO's id? Right now I use these: (PHOTO is no where in the picture) SELECT * from COLOR WHERE photo_num='xxx'; SELECT * from SIZE WHERE photo_num='xxx'; Q2: How will the SELECT query look if PHOTO id was used in COLOR, SIZE?

    Read the article

  • Anyone have a good solution for scraping the HTML source of a page with content (in this case, HTML

    - by phpwns
    Anyone have a good solution for scraping the HTML source of a page with content (in this case, HTML tables) generated with Javascript? An embarrassingly simple, though workable solution using Crowbar: <?php function get_html($url) // $url must be urlencode(d) { $context = stream_context_create(array( 'http' => array('timeout' => 120) // HTTP timeout in seconds )); $html = substr(file_get_contents('http://127.0.0.1:10000/?url=' . $url . '&delay=3000&view=browser', 0, $context), 730, -32); // substr removes HTML from the Crowbar web service, returning only the $url HTML return $html; } ?> The advantage to using Crowbar is that the tables will be rendered (and accessible) thanks to the headless mozilla-based browser. The problem, of course, is being dependent on on an external web service, especially given that SIMILE seems to undergo regular server maintenance. :( A pure php solution would be nice, but any functional (and reliable) alternatives would be great.

    Read the article

  • Postgres : Post statement (or insert) asynchronous, non-blocking processing.

    - by Hassan Syed
    I'm wondering if it is possible, that after a collection of rows is inserted, to initiate an operation that is executed asynchronously, is non-blocking, and doesn't need to inform the originator of the request - of the result. I am working with large amounts of events and I can guarantee that the post-insert logic will not fail -- I just want to have a single insert thread in my event-sources, and I want this thread to keep flying without blocking, and without being responsible for any post-delivery book-keeping. I can tell you that I would potentially have a 100 of these jobs executing concurrently and each job might operate on 5 tables with anywhere between 200-1000 inserts on each of these tables. A hint in the right direction should be enough.

    Read the article

  • Python fCGI + sqlAlchemy = malformed header from script. Bad header=FROM tags : index.py

    - by crgwbr
    I'm writing an Fast-CGI application that makes use of sqlAlchemy & MySQL for persistent data storage. I have no problem connecting to the DB and setting up ORM (so that tables get mapped to classes); I can even add data to tables (in memory). But, as soon as I query the DB (and push any changes from memory to storage) I get a 500 Internal Server Error and my error.log records malformed header from script. Bad header=FROM tags : index.py, when tags is the table name. Any idea what could be causing this? Also, I don't think it matters, but its a Linux development server talking to an off-site (across the country) MySQL server.

    Read the article

  • How can I use linq to build an object from 1 row of data?

    - by Hcabnettek
    Hi All, I have a quick linq question. I have a stored proc that should return one row of data. I would like to use a lambda to build an object. Here's what I'm currently doing which works, but I know I should be able to use First instead of Select except I can't seem to get the syntax correct. Can anyone straighten me out here? Thanks for any help. var location = new GeoLocationDC(); DataSet ds = db.ExecuteDataSet(dbCommand); if(ds.Tables[0].Rows.Count == 1) { var rows = ds.Tables[0].AsEnumerable(); var x = rows.Select( c => new GeoLocationDC { Latitude = Convert.ToInt32(c.Field<string>("LATITUDE")), Longitude = Convert.ToInt32(c.Field<string>("LONGITUDE")) }).ToList(); if(x.Count > 0 ) { location = x[0]; } Cheers, ~ck }

    Read the article

  • OracleDataAdapter returns no rows, but the query string works in SQLDeveloper

    - by belzebu
    visual studion 2008 oracle db 11.1.0.7 oracle client for .NET I have a relatively simple query, that selects the rows from across multiple tables (up to 4) using joins. OracleDataAdapter returns no rows for the only dataset's table, but if I copy and paste that query in SQLDeveloper then I get the desired results. I can get the data from other tables using the adapter with no problem, but it seems like it struggles with the bit longer selection query (string length is ~ 300 (not that much at all)) Connection string for the connection is 100% correct. Any ideas? thank you...

    Read the article

  • How do I correctly use two Not Exists statements in a where clause using Access SQL VBA?

    - by Bryan
    I have 3 Tables: NotHeard,analyzed,analyzed2. In each of these tables I have two columns named UnitID and Address. What I'm trying to do right now is to select all of the records for the columns UnitID and Address from NotHeard that don't appear in either analyzed or analyzed2. The SQL statement I created was as follows: SELECT UnitID, Address INTO [NotHeardByEither] FROM [NotHeard] Where NOT EXISTS( Select analyzed.UnitID FROM analyzed WHERE [NotHeard].UnitID = analyzed.UnitID) or NOT EXISTS( Select analyzed2.UnitID FROM analyzed2 WHERE [NotHeard].UnitID = analyzed2.UnitID) Group BY UnitID, Address I thought this would work since I've used the single NOT EXISTS subquery line and it has worked just fine for me in the past. The above query however returns the same data that is in the NotHeard table whereas if I take out the or NOT EXISTS part it works correctly. Any ideas as to what I'm doing wrong or how to do what I'm wanting to do?

    Read the article

  • Sort a GridView Column related to other Table

    - by Tim
    Hello, i have a GridView bound to a DataView. Some columns in the DataView's table are foreignkeys to related tables(f.e. Customer). I want to enable sorting for these columns too, but all i can do is sorting the foreignkey(fiCustomer) and not the CustomerName. I have tried this without success(" Cannot find column ERP_Customer.CustomerName "): <asp:TemplateField HeaderText="Customer" SortExpression="ERP_Customer.CustomerName" > A tried also the DataViewManager, but i've a problem to detect the table to sort: Dim viewManager As New DataViewManager(Me.dsERP) viewManager.DataViewSettings(dsERP.ERP_Charge).RowFilter = filter viewManager.DataViewSettings(dsERP.ERP_Charge).Sort = sort 'sort is the GridView's SortExpression Me.GrdCharge.DataSource = viewManager.CreateDataView(dsERP.ERP_Charge) I have to apply the sort on a distinct table of the DataViewManager, but this table would differ on the related tables. I have bound the TemplateColumns in Codebehind in RowDataBound-Event f.e.: Dim LblCustomer As Label = DirectCast(e.Row.FindControl("LblCustomer"), Label) LblCustomer.Text = drCharge.ERP_CustomerRow.CustomerName 'drCharge inherits DataRow What is the recommended way to sort a GridView on columns related to another table?

    Read the article

  • Create Access databases programatically through vb.net

    - by user87225
    Let me preface this by saying that I know this is a stupid way to go about this, but it needs to be handled in this way. I need to make an application that from a master database creates a number of access database files (tables of a larger db), then these are manually given to users who fill in data, the database files are emailed back to a user who, through the application, combines them again. The only part of this that I am unsure about is problematically creating the access db's. I have read that through Microsoft Jet OLE DB Provider and Microsoft ADO Ext I can create them (the tables and data), but I also need forms. I have yet to start writing anything and this is away from my area of work, so any insight/links would be much appreciated. Also, I would hope to be able to write this in the free express version of visual studio. Are there components needed that would prevent me from this? Thanks.

    Read the article

  • PHP/MySQL: Check if something 'belongs-to' something else?

    - by Nebs
    I have two tables: Stores and Items. The relationship is: Stores 1---* Items In PHP/MySQL what would be the best (fastest/simplest) way to check if a particular item belongs to a particular store. In other words given for example: $store_id = 1; $item_id = 12; I want to check if item 12 belongs to store 1 (and not some other store). I usually do a select on Items matching both the store_id and item_id and limit the results to 1. Then check how many rows (0 or 1) were returned with mysql_num_rows. Is there a better way? Update: Both tables have an "id" column. The Items table has a "store_id" column.

    Read the article

  • multithreading with database

    - by Darsin
    I am looking out for a strategy to utilize multithreading (probably asynchronous delegates) to do a synchronous operation. I am new to multithreading so i will outline my scenario first. This synchronous operation right now is done for one set of data (portfolio) based on the the parameters provided. The (psudeo-code) implementation is given below: public DataSet DoTests(int fundId, DateTime portfolioDate) { // Get test results for the portfolio // Call the database adapter method, which in turn is a stored procedure, // which in turns runs a series of "rule" stored procs and fills a local temp table and returns it back. DataSet resultsDataSet = GetTestResults(fundId, portfolioDate); try { // Do some local processing on the results DoSomeProcessing(resultsDataSet); // Save the results in Test, TestResults and TestAllocations tables in a transaction. // Sets a global transaction which is provided to all the adapter methods called below // It is defined in the Base class StartTransaction("TestTransaction"); // Save Test and get a testId int testId = UpdateTest(resultsDataSet); // Adapter method, uses the same transaction // Update testId in the other tables in the dataset UpdateTestId(resultsDataSet, testId); // Update TestResults UpdateTestResults(resultsDataSet); // Adapter method, uses the same transaction // Update TestAllocations UpdateTestAllocations(resultsDataSet); // Adapter method, uses the same transaction // It is defined in the base class CommitTransaction("TestTransaction"); } catch { RollbackTransaction("TestTransaction"); } return resultsDataSet; } Now the requirement is to do it for multiple set of data. One way would be to call the above DoTests() method in a loop and get the data. I would prefer doing it in parallel. But there are certain catches: StartTransaction() method creates a connection (and transaction) every time it is called. All the underlying database tables, procedures are the same for each call of DoTests(). (obviously). Thus my question are: Will using multithreading anyway improve performance? What are the chances of deadlock especially when new TestId's are being created and the Tests, TestResults and TestAllocations are being saved? How can these deadlocked be handled? Is there any other more efficient way of doing the above operation apart from looping over the DoTests() method repeatedly?

    Read the article

< Previous Page | 133 134 135 136 137 138 139 140 141 142 143 144  | Next Page >