Search Results

Search found 7391 results on 296 pages for 'record locking'.

Page 218/296 | < Previous Page | 214 215 216 217 218 219 220 221 222 223 224 225  | Next Page >

  • I need to simplify a MySQL sub query for performance - please help

    - by Richard
    I have the following query which is takin 3 seconds on a table of 1500 rows, does someone know how to simplify it? SELECT dealers.name, dealers.companyName, dealer_accounts.balance FROM dealers INNER JOIN dealer_accounts ON dealers.id = dealer_accounts.dealer_id WHERE dealer_accounts.id = ( SELECT id FROM dealer_accounts WHERE dealer_accounts.dealer_id = dealers.id AND dealer_accounts.date < '2010-03-30' ORDER BY dealer_accounts.date DESC, dealer_accounts.id DESC LIMIT 1 ) ORDER BY dealers.name I need the latest dealer_accounts record for each dealer by a certain date with the join on the dealer_id field on the dealer_accounts table. This really should be simple, I don't know why I am struggling to find something.

    Read the article

  • What to do with twitter oauth token once retreived?

    - by mcintyre321
    I'm writing a web app that will use twitter as its primary log on method. I've written code which gets the oauth token back from Twitter. My plan is now to Find the entry in my Users table for the twitter username retreived using the token, or create the entry if necessary Update the Users.TwitterOAuthToken column with the new OAuth token Create a permanent cookie with a random guid on the site and insert a record into my UserCookies table matching Cookie to User when a request comes in I will look for the browser cookie id in the UserCookies table, then use that to figure out the user, and make twitter requests on their behalf Write the oauth token into some pages as a js variable so that javascript can make requests on behalf of the user If the user clears his/her cookies the user will have to log in again to twitter Is this the correct process? Have I created any massive security holes? thanks!

    Read the article

  • "Easiest" way to track unique visitors to a page, in real time?

    - by Cooper
    I need to record in "real time" (perhaps no more than 5 minute delay?) how many unique visitors a given page on my website has had in a given time period. I seek an "easy" way to do this. Preferably the results would be available via a database query. Two things I've tried that failed (so far): Google Analytics: Does the tracking/reporting, but not in real time - results are delayed by hours. Mint Analytics ( http://www.haveamint.com/ ): Tracks in real time, but seems to aggregate data in a way that prevents reporting of unique visitors to a single page over an arbitrary time frame. So, does anyone know how to make Mint Analytics do what I want, or can anyone recommend an analytics package or programmed approach that will do what I need?

    Read the article

  • I'm having a hard time wrapping my head around handling the Activity Lifecycle...

    - by kefs
    So it seems i've created a fatal flaw and coded an app before understanding/handling rotation/lifecycle events.. Currently, all of my code is in onCreate of each activity. I've read a lot of lifecycle tutorials online, including the official dev guide info, but i'm still having an almost unbelievably hard time trying to wrap my head around the rotation/lifecycle events/methods and when to use them correctly. For example, my app currently has an activity that opens the db, inserts a record, then closes the db.. if i rotate my screen on this activity, the data is re-entered into the db. Using the available lifecycle events (onPause(), onResume(), etc..), how would I prevent this db call from happening again? Would I have to pass a variable through the state saying that the db call has been done, and not to do it again? Thanks in advance..

    Read the article

  • Rails 3 Nested Forms

    - by Mike
    I have a Person model and an Address Model: class Person < ActiveRecord::Base has_one :address accepts_nested_attributes_for :address end class Address < ActiveRecord::Base belongs_to :person end In my people controller I have @person.build_address in my new action. My forms builds correctly. The problem is that when I submit the form, a person record and an address record is created but they aren't linked via the address_id column in the Person table. Am I missing a step in the controller? Thanks! New Action UPDATE def new @person = Person.new @person.build_address respond_to do |format| format.html # new.html.erb format.xml { render :xml => @person } end end Form Code UPDATE <%= form_for(@person) do |f| %> <% if @person.errors.any? %> <div id="error_explanation"> <h2><%= pluralize(@person.errors.count, "error") %> prohibited this person from being saved:</h2> <ul> <% @person.errors.full_messages.each do |msg| %> <li><%= msg %></li> <% end %> </ul> </div> <% end %> <div class="field"> <%= f.label :first_name %><br /> <%= f.text_field :first_name %> </div> <div class="field"> <%= f.label :last_name %><br /> <%= f.text_field :last_name %> </div> <div class="field"> <%= f.label :email %><br /> <%= f.text_field :email %> </div> <div class="field"> <%= f.label :telephone %><br /> <%= f.text_field :telephone %> </div> <div class="field"> <%= f.label :mobile_phone %><br /> <%= f.text_field :mobile_phone %> </div> <div class="field"> <%= f.label :date_of_birth %><br /> <%= f.date_select :date_of_birth %> </div> <div class="field"> <%= f.label :gender %><br /> <%= f.select(:gender, Person::GENDER_TYPES) %> </div> <div class="field"> <%= f.label :notes %><br /> <%= f.text_area :notes %> </div> <div class="field"> <%= f.label :person_type %><br /> <%= f.select(:person_type, Person::PERSON_TYPES) %> </div> <%= f.fields_for :address do |address_fields| %> <div class="field"> <%= address_fields.label :street_1 %><br /> <%= address_fields.text_field :street_1 %> </div> <div class="field"> <%= address_fields.label :street_2 %><br /> <%= address_fields.text_field :street_2 %> </div> <div class="field"> <%= address_fields.label :city %><br /> <%= address_fields.text_field :city %> </div> <div class="field"> <%= address_fields.label :state %><br /> <%= address_fields.select(:state, Address::STATES) %> </div> <div class="field"> <%= address_fields.label :zip_code %><br /> <%= address_fields.text_field :zip_code %> </div> <% end %> <div class="actions"> <%= f.submit %> </div> <% end %>

    Read the article

  • Asynchronous SQL Operations

    - by Paul Hatcherian
    I've got a problem I'm not sure how best to solve. I have an application which updates a database in response to ad hoc requests. One request in particular is quite common. The request is an update that by itself is quite simple, but has some complex preconditions. For this request the business layer first requests a set of data from the data layer. The business logic layer evaluated the data from the database and parameters from the request, from this the action to be performed is determined, and the request's response message(s) are created. The business layer now executes the actual update command that is the purpose of the request. This last step is the problem, this command is dependent on the state of the database, which might have changed since the business logic ran. Locking down the data read in this operation across several round-trips to the database doesn't seem like a good idea either. Is there a 'best-practice' way to accomplish something like this? Thanks!

    Read the article

  • Violation of primary key constraint, multiple users

    - by MC.
    Lets say UserA and UserB both have an application open and are working with the same type of data. UserA inserts a record into the table with value 10 (PrimaryKey='A'), UserB does not currently see the value UserA entered and attempts to insert a new value of 20 (PrimaryKey='A'). What I wanted in this situation was a DBConcurrencyException, but instead what I have is a primary key violation. I understand why, but I have no idea how to resolve this. What is a good practice to deal with such a circumstance? I do not want to merge before updating the database because I want an error to inform the user that multiple users updated this data.

    Read the article

  • Query on Triggers..

    - by RBA
    Created One Trigger in Oracle.. SQL> CREATE OR REPLACE TRIGGER student_after_insert 2 AFTER INSERT 3 ON student 4 FOR EACH ROW 5 BEGIN 6 @hello.pl 9 END student_after_insert; 10 / Contents of hello.pl are:- BEGIN DBMS_OUTPUT.PUT_LINE('hello world'); END; And.. the result is pretty good, as the content of hello.pl is displayed on screen while inserting a record.. Now, the query is -- When i change the content of the hello.pl file, after exiting from oracle, and then logging again, It doesn't shows the updated contents, instead it shows the previous content.. I noticed that, if i drop the trigger and create it again, then it is working fine.. Why is it happening so.. And what is the solution to this problem..

    Read the article

  • using NEWSEQUENTIALID() with UPDATE Trigger

    - by Ram
    I am adding a new GUID/Uniqueidentifier column to my table. ALTER TABLE table_name ADD VersionNumber UNIQUEIDENTIFIER UNIQUE NOT NULL DEFAULT NEWSEQUENTIALID() GO And when ever a record is updated in the table, I would want to update this column "VersionNumber". So I create a new trigger CREATE TRIGGER [DBO].[TR_TABLE_NAMWE] ON [DBO].[TABLE_NAME] AFTER UPDATE AS BEGIN UPDATE TABLE_NAME SET VERSIONNUMBER=NEWSEQUENTIALID() FROM TABLE_NAME D JOIN INSERTED I ON D.ID=I.ID/* some ID which is used to join*/ END GO But just realized that NEWSEQUENTIALID() can only be used with CREATE TABLE or ALTER TABLE. I got this error The newsequentialid() built-in function can only be used in a DEFAULT expression for a column of type 'uniqueidentifier' in a CREATE TABLE or ALTER TABLE statement. It cannot be combined with other operators to form a complex scalar expression. Is there a workaround for this ? Edit1: Changing NEWSEQUENTIALID() to NEWID() in the trigger solves this, but I am indexing this column and using NEWID() would be sub-optimal

    Read the article

  • Need Insight - What is the best practice for syncing up a production database that will be used on a

    - by james
    I have a site set up using CakePHP and MySQL and I want to work on a test database without disrupting my live site in case something goes wrong. I have another busy site, but my test site runs off the live database which can be occasionally nerve wracking. What do I do if I change a table name in the test db and I want it changed in the live database? Or if I remove a record from the test database. Is there a way to diff the changes? How do I even merge those changes? How does this interfere with live user edits and things of that nature? Hopefully some of you working devs can share some insight!

    Read the article

  • Generate MySQL data dump in SQL from PHP

    - by Álvaro G. Vicario
    I'm writing a PHP script to generate SQL dumps from my database for version control purposes. It already dumps the data structure by means of running the appropriate SHOW CREATE .... query. Now I want to dump data itself but I'm unsure about the best method. My requirements are: I need a record per row Rows must be sorted by primary key SQL must be valid and exact no matter the data type (integers, strings, binary data...) Dumps should be identical when data has not changed I can detect and run mysqldump as external command but that adds an extra system requirement and I need to parse the output in order to remove headers and footers with dump information I don't need (such as server version or dump date). I'd love to keep my script as simple as I can so it can be hold in an standalone file. What are my alternatives?

    Read the article

  • Reusing an anonymous parameter in a prepared statement

    - by Chris Lieb
    I am customizing the insert SQL generated by hibernate and have hit an issue. When Hibernate generates the query by itself, it inserts data into the first two columns of the table, but this causes a database error since all four columns of the table are non-nullable. For the insert to be performed properly, it must insert the same data into two columns of the new record. This means that I need Hibernate to bind the same data to two different parameters in the query (prepared statement) that I am writing. Is there some SQL syntax that allows me to refer to anonymous parameters bound to a prepared statement in an order different from which they are bound? Details REF_USER_PAGE_XREF ---------------------------------------- PK FK1 | NETWORK_ID | VARCHAR2(100) PK FK1 | PAGE_PATH | VARCHAR2(1000) | USER_LAST_UPDT | VARCHAR2(100) | TMSP_LAST_UPDT | DATE insert into REF_USER_ROLE_XREF( NETWORK_ID, PAGE_PATH, TMSP_LAST_UPDT, USER_LAST_UPDT) values ( ?, /* want to insert the same data here */ ?, ?, /* and here */ (select to_char(sysdate, 'DD-MON-YY') from dual) I want to insert the same data into the first and third anonymous parameters.

    Read the article

  • django updating m2m field

    - by Marconi
    I have a model service and a ModelForm named Service which I use to add and update the service model. The model looks like this: class Service(models.Model): categories = models.ManyToManyField(Category) The categories field is displayed as a tag with that allows multiple selection. It works well when I'm adding a new record but when I'm updating it, only one service is showing up on the request.POST['categories'] even if I selected multiple categories. I tried dumping the request object and I can see that the categories is showing something like: u'categories': [u'3', u'4', u'2'] I tried calling the request._get_post() and it did return only 1 category, hence the request.POST['categories'] returns only 1. Anybody who knows what's happening and how to fix it?

    Read the article

  • Is shortening properties names worth it?

    - by raam86
    in how to node Blog rolling with node.js and mongoDB the author mentions it's a good idea to shorten proprieties names: ....oft-reported issue with mongoDB is the size of the data on the disk... each and every record stores all the field-names .... This means that it can often be more space-efficient to have properties such as 't', or 'b' rather than 'title' or 'body', however for fear of confusion I would avoid this unless truly required! I am aware of solutions of how to do it I am more intrested in when is it truly required?

    Read the article

  • Get all descendants types of base class

    - by user1260827
    I have a base class called BaseEvent and several descendants classes: public class BaseEvent { // the some properties ... } [MapInheritance(MapInheritanceType.ParentTable)] public class Film : BaseEvent { // the some properties ... } [MapInheritance(MapInheritanceType.ParentTable)] public class Concert : BaseEvent { // the some properties ... } I have a code which create the BaseEvent instance at runtime: BaseEvent event = new BaseEvent(); //assign values for a properties ... baseEvent.XPObjectType = Database.XPObjectTypes.SingleOrDefault(t => t.TypeName == "MyApp.Module.BO.Events.BaseEvent"); Now, this event will be shows in BaseEvent list view. I want to do the following: when a user click Edit button then show in list view lookup field with all descendants types. And when user saves record change ObjectType to selected value. How can I do this? Thanks. PS. this is asp.net app.

    Read the article

  • Retrieve rows where a value exists within a comma separated list

    - by Klaaz
    I like to reverse this query: SELECT * FROM table WHERE status IN ( option,option1,option2 ); in a query like SELECT * FROM table WHERE status contains ( 'option' ); Where field 'status' column contains (by example): 'option,option1'. When I use SELECT * FROM table WHERE status LIKE '%option%' ); It also selects the rows with a 'status' column that only contains 'option1' Is this possible? example data: id,name,status 1,'test1','option,option1' 2,'test2','option,option2' 3,'test3','option2' 4,'test4','option2,option3' 5,'test5','option' SELECT * FROM table WHERE status contains ( 'option' ); This query should select select record 1,2 and 5. 'status' field type is varchar. The problem is that the status fields contains data that is almost alike, exept from the added number to option. Off course this is a made up example but the real thing has this kind of parameters

    Read the article

  • Linq To Sql Entity Updated from Trigger

    - by James Helms
    I have a Table called Address. I have a Trigger for insert on that table that does some spacial calculations on the address that determines what neighborhood boundaries it is in. address = new Address { Street = this.Street, City = this.City, State = this.State, ZipCode = this.ZipCode, latitude = this.Latitude, longitude = this.Longitude, YearBuilt = this.YearBuilt, LotSize = this.LotSize, FinishedSize = this.FinishedSize, Bedrooms = this.Bedrooms, Bathrooms = this.Bathrooms, UseCode = this.UseCode, HOA = this.HOA, UpdateDate = DateTime.Now }; db.AddToAddresses(address); db.SaveChanges(); In the database i can clearly see that the Trigger ran and updated the neighborhoodID in the address table for the row. I tried to just reload that record to get the assigned id like this: address = (from a in db.Addresses where a.AddressID == address.AddressID select a).First(); In the debugger i can clearly see that the address.AddressID is correct, entity doesn't update in memory. Is there any work around for this?

    Read the article

  • Object oriented n-tier design. Am I abstracting too much? Or not enough?

    - by max
    Hi guys, I'm building my first enterprise grade solution (at least I'm attempting to make it enterprise grade). I'm trying to follow best practice design patterns but am starting to worry that I might be going too far with abstraction. I'm trying to build my asp.net webforms (in C#) app as an n-tier application. I've created a Data Access Layer using an XSD strongly-typed dataset that interfaces with a SQL server backend. I access the DAL through some Business Layer Objects that I've created on a 1:1 basis to the datatables in the dataset (eg, a UsersBLL class for the Users datatable in the dataset). I'm doing checks inside the BLL to make sure that data passed to DAL is following the business rules of the application. That's all well and good. Where I'm getting stuck though is the point at which I connect the BLL to the presentation layer. For example, my UsersBLL class deals mostly with whole datatables, as it's interfacing with the DAL. Should I now create a separate "User" (Singular) class that maps out the properties of a single user, rather than multiple users? This way I don't have to do any searching through datatables in the presentation layer, as I could use the properties created in the User class. Or would it be better to somehow try to handle this inside the UsersBLL? Sorry if this sounds a little complicated... Below is the code from the UsersBLL: using System; using System.Data; using PedChallenge.DAL.PedDataSetTableAdapters; [System.ComponentModel.DataObject] public class UsersBLL { private UsersTableAdapter _UsersAdapter = null; protected UsersTableAdapter Adapter { get { if (_UsersAdapter == null) _UsersAdapter = new UsersTableAdapter(); return _UsersAdapter; } } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Select, true)] public PedChallenge.DAL.PedDataSet.UsersDataTable GetUsers() { return Adapter.GetUsers(); } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Select, false)] public PedChallenge.DAL.PedDataSet.UsersDataTable GetUserByUserID(int userID) { return Adapter.GetUserByUserID(userID); } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Select, false)] public PedChallenge.DAL.PedDataSet.UsersDataTable GetUsersByTeamID(int teamID) { return Adapter.GetUsersByTeamID(teamID); } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Select, false)] public PedChallenge.DAL.PedDataSet.UsersDataTable GetUsersByEmail(string Email) { return Adapter.GetUserByEmail(Email); } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Insert, true)] public bool AddUser(int? teamID, string FirstName, string LastName, string Email, string Role, int LocationID) { // Create a new UsersRow instance PedChallenge.DAL.PedDataSet.UsersDataTable Users = new PedChallenge.DAL.PedDataSet.UsersDataTable(); PedChallenge.DAL.PedDataSet.UsersRow user = Users.NewUsersRow(); if (UserExists(Users, Email) == true) return false; if (teamID == null) user.SetTeamIDNull(); else user.TeamID = teamID.Value; user.FirstName = FirstName; user.LastName = LastName; user.Email = Email; user.Role = Role; user.LocationID = LocationID; // Add the new user Users.AddUsersRow(user); int rowsAffected = Adapter.Update(Users); // Return true if precisely one row was inserted, // otherwise false return rowsAffected == 1; } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Update, true)] public bool UpdateUser(int userID, int? teamID, string FirstName, string LastName, string Email, string Role, int LocationID) { PedChallenge.DAL.PedDataSet.UsersDataTable Users = Adapter.GetUserByUserID(userID); if (Users.Count == 0) // no matching record found, return false return false; PedChallenge.DAL.PedDataSet.UsersRow user = Users[0]; if (teamID == null) user.SetTeamIDNull(); else user.TeamID = teamID.Value; user.FirstName = FirstName; user.LastName = LastName; user.Email = Email; user.Role = Role; user.LocationID = LocationID; // Update the product record int rowsAffected = Adapter.Update(user); // Return true if precisely one row was updated, // otherwise false return rowsAffected == 1; } [System.ComponentModel.DataObjectMethodAttribute (System.ComponentModel.DataObjectMethodType.Delete, true)] public bool DeleteUser(int userID) { int rowsAffected = Adapter.Delete(userID); // Return true if precisely one row was deleted, // otherwise false return rowsAffected == 1; } private bool UserExists(PedChallenge.DAL.PedDataSet.UsersDataTable users, string email) { // Check if user email already exists foreach (PedChallenge.DAL.PedDataSet.UsersRow userRow in users) { if (userRow.Email == email) return true; } return false; } } Some guidance in the right direction would be greatly appreciated!! Thanks all! Max

    Read the article

  • Calling C++/CLI Method with System::DateTime parameter requires 'ValueType' as a parameter?

    - by David Ipsen
    I'm attempting to call a method written in C++/CLI from C#. The C++/CLI code is used to update a TIMESTAMP column in an Oracle database, given a record ID and the System::DateTime object which is the .NET compatible data type for Oracle's TIMESTAMP type. The method I am calling has the following prototype: bool ChangeJobUpdateDate (int jobIdIn, System::DateTime^ updateDateIn) I've added a reference to this DLL project in a test project that I made; I'm writing the tests in C#. However, when I try to call this method from the C# unit test project, the function appears to have the following method declaration (via intellisense): bool ChangeJobUpdateDate (int jobIdIn, ValueType updateDateIn) I'm admittedly not that familiar with C++/CLI, so is there something I'm missing?

    Read the article

  • How can I tell if an ADODB::_RecordsetPtr has already been created?

    - by scottm
    I am trying to write a class that uses ADO to retrieve SQL records. The intent is for the class to maintain one private recordset an other methods move forward, retrieve fields, etc. This is a basic example of my class: class SqlADO { private: ADODB::_RecordsetPtr m_recordset; public: void Open(); //open the connection void Execute(const char* sql); // creates or replaces current recordset void Next(); //moves recordset cursor forward void Field(const char* fieldName); //retrieves field name from current record of the recordset }; My Questions: In the Execute method, how can I check to see that the recordset instance has been created (or do I need to) so that I can close it first? Do you know of any good ADO COM Interop references?

    Read the article

  • Table Variables in SSIS

    - by aceinthehole
    In one SQL Task can I create a table variable DELCARE @TableVar TABLE (...) Then in another SQL Task or DataSource destination and select or insert into the table variable? The other option I have considered is using a Temp Table. CREATE TABLE #TempTable (...) I would prefer to use Table Variable so that it remains in memory. But can use temp table if it is not possible to use table variable. Also I cannot use the record set destination as I need to preform straight SQL tasks on it later on.

    Read the article

  • Using Linq, how to separate a list in to grouped objects by name?

    - by Dr. Zim
    I have a table where a record looks like this varchar(255) Name varchar(255) Text varchar(255) Value Name is the DDL name, Text is what is displayed, and Value is returned upon selection. There are between one and twenty options for each Name. Without iterating though each option like a cursor, is there any way to pull out a list of objects, one for each unique DDL Name, using Linq and C#? A sample of the data: Beds '4 (10)' 4 Beds '5 (1)' 5 Beds '7 (1)' 7 Baths 'NA (13)' NULL Baths '0 (1)' 0 Baths '1 (13)' 1 I was thinking about doing an outer select to get the unique Names, then an inner select to get the list of options for it, then return the set as a List of a set of Lists.

    Read the article

  • inconsistent setTexture behavior in cocos2d on iPhone after using CCAnimate/CCAnimation

    - by chillid
    Hi, I have a character that goes through multiple states. The state changes are reflected by means of a sprite image (texture) change. The state change is triggered by a user tapping on the sprite. This works consistently and quite well. I then added an animation during State0. Now, when the user taps - setTexture gets executed to change the texture to reflect State1, however some of the times (unpredictable) it does not change the texture. The code flows as below: // 1. // Create the animation sequence CGRect frame1Rect = CGRectMake(0,32,32,32); CGRect frame2Rect = CGRectMake(32,32,32,32); CCTexture2D* texWithAnimation = [[CCTextureCache sharedTextureCache] addImage:@"Frames0_1_thinkNthickoutline32x32.png"]; id anim = [[[CCAnimation alloc] initWithName:@"Sports" delay:1/25.0] autorelease]; [anim addFrame:[CCSpriteFrame frameWithTexture:texWithAnimation rect:frame1Rect offset:ccp(0,0)]]; [anim addFrame:[CCSpriteFrame frameWithTexture:texWithAnimation rect:frame2Rect offset:ccp(0,0)]]; // Make the animation sequence repeat forever id myAction = [CCAnimate actionWithAnimation: anim restoreOriginalFrame:NO]; // 2. // Run the animation: sports = [[CCRepeatForever alloc] init]; [sports initWithAction:myAction]; [self.sprite runAction:sports]; // 3. stop action on state change and change texture: NSLog(@"Stopping action"); [sprite stopAction:sports]; NSLog(@"Changing texture for kCJSports"); [self setTexture: [[CCTextureCache sharedTextureCache] addImage:@"SportsOpen.png"]]; [self setTextureRect:CGRectMake(0,0,32,64)]; NSLog(@"Changed texture for kCJSports"); Note that all the NSLog lines get logged - and the texture RECT changes - but the image/texture changes only some of the times - fails for around 10-30% of times. Locking/threading/timing issue somewhere? My app (game) is single threaded and I only use the addImage and not the Async version. Any help much appreciated.

    Read the article

  • How should I lock the table in this VB6 / Access application?

    - by Brian Hooper
    I'm working on a VB6 application using an Access database. The application writes messages to a log table from time to time. Several instances of the application may be running simultaneously and to distinguish them they each have their own run number. The run number is deduced from the log table thus... Set record_set = New ADODB.Recordset query_string = "SELECT MAX(RUN_NUMBER) + 1 AS NEW_RUN_NUMBER FROM ERROR_LOG" record_set.CursorLocation = adUseClient record_set.Open query_string, database_connection, adOpenStatic, , adCmdText record_set.MoveLast If IsNull(record_set.Fields("NEW_RUN_NUMBER")) Then run_number = 0 Else run_number = record_set.Fields("NEW_RUN_NUMBER") End If command_string = "INSERT INTO ERROR_LOG (RUN_NUMBER, SEVERITY, MESSAGE) " & _ " VALUES (" & Str$(run_number) & ", " & _ " " & Str$(SEVERITY_INFORMATION) & ", " & _ " 'Run Started'); " database_connection.Execute command_string Obviously there is a small gap between the calculation of the run number and the appearance of the new row in the database, and to prevent another instance getting access between the two operations I'd like to lock the table; something along the lines of SET TRANSACTION READ WRITE RESERVING ERROR_LOG FOR PROTECTED WRITE; How should I go about doing this? Would locking the recordset do any good (the row in the record set doesn't match any particular row in the database)?

    Read the article

  • rails - form to disply non-input type fields in nested form

    - by nktokyo
    Hi, I guess this is a newbie question, but what is the syntax in a form to show contents of fields not as a text box/area, but rather like label would appear. <% form_for @user do |f| %> <% f.fields_for :user_ingreds do |builder| %> <p> <%= builder.??? %> </p> <% end %> <% end%> user has many user_ingreds and accepts_nested_attributes for user_ingreds. Basically I want to make a list of user_ingreds where the user can't edit the data but can remove the record from the list via a button - however the fields_for builder doesn't recognize a direct call to to the fields in user_ingreds model (ie, builder.user_id throws and error.

    Read the article

< Previous Page | 214 215 216 217 218 219 220 221 222 223 224 225  | Next Page >