Search Results

Search found 56342 results on 2254 pages for 'object database'.

Page 504/2254 | < Previous Page | 500 501 502 503 504 505 506 507 508 509 510 511  | Next Page >

  • How to handle ids and polymorphic associations in views if compound keys are not supported?

    - by duncan
    I have a Movie plan table: movie_plans (id, description) Each plan has items, which describe a sequence of movies and the duration in minutes: movie_plan_items (id, movie_plan_id, movie_id, start_minutes, end_minutes) A specific instance of that plan happens in: movie_schedules (id, movie_plan_id, start_at) However the schedule items can be calculated from the movie_plan_items and the schedule start time by adding the minutes create view movie_schedule_items as select CONCAT(p.id, '-', s.id) as id, s.id as movie_schedule_id, p.id as movie_plan_item_id, p.movie_id, p.movie_plan_id, (s.start_at + INTERVAL p.start_minutes MINUTE) as start_at, (s.start_at + INTERVAL p.end_minutes MINUTE) as end_at from movie_plan_items p, movie_schedules s where s.movie_plan_id=p.movie_plan_id; I have a model over this view (readonly), it works ok, except that the id is right now a string. I now want to add a polymorphic property (like comments) to various of the previous tables. Therefore for movie_schedule_items I need a unique and persistent numeric id. I have the following dilemma: I could avoid the id and have movie_schedule_items just use the movie_plan_id and movie_schedule_id as a compound key, as it should. But Rails sucks in this regard. I could create an id using String#hash or a md5, thus making it slower or collision prone (and IIRC String#hash is no longer persistent across processes in Ruby 1.9) Any ideas on how to handle this situation?

    Read the article

  • Conditional PIVOT/transform problem

    - by IanC
    Hi folks I have a table with three columns, which we'll call ID1, ID2, and Value. Sample data: ID ID1 Value 1 1 0 1 2 1 1 3 1 1 3 2 1 4 0 1 4 1 1 5 0 1 5 2 2 1 2 Value is limited to 0, 1, or 2. What I need to do is pivot/transform this data into a column-based count of how many times each possible Value appears, grouped by ID, ID1. The output of the above should be: ID ID1 Val0 Val1 Val2 1 1 1 0 0 1 2 0 2 0 1 3 0 1 1 1 4 1 1 0 1 5 1 0 1 2 1 0 0 1 I'm using SQL Server 2008. How do I do this?

    Read the article

  • db optimization - have a total field or query table?

    - by Dorian Fife
    I have an app where users get points for actions they perform - either 1 point for an easy action or 2 for a difficult one. I wish to display to the user the total number of points he got in my app and the points obtained this week (since Monday at midnight). I have a table that records all actions, along with their time and number of points. I have two alternatives and I'm not sure which is better: Every time the user sees the report perform a query and sum the points the user got Add two fields to each user that records the number of points obtained so far (total and weekly). The weekly points value will be set to 0 every Monday at midnight. The first option is easier, but I'm afraid that as I'll get many users and actions queries will take a long time. The second option bares the risk of inconsistency between the table of actions and the summary values. I'm very interested in what you think is the best alternative here. Thanks, Dorian

    Read the article

  • Table naming convention?

    - by MattSlay
    In our manufacturing shop, each Employee hits the time clock every time they change Jobs or Machines (work centers) during their work day. Each record created in the Time Clock app has foreign keys that link the record to: the Employee, the Job, and the Machine which they are about to operate. I’m trying to determine the best name for this table… If I were tempted to call it ClockRecords or TimeClockRecords, why wouldn’t I also consider naming it JobTimeRecords, or why not MachineTimeRecords. Any ideas on a good name?

    Read the article

  • Financial Market Developer dilemma...

    - by Sahat
    ...In the future I am planning to work in the financial sector as a programmer. I have a couple of options right now (1 or 2): Learn and master .NET since presumably that's widely used in that industry OR Learn the programming concepts, learn algorithms, learn a little bit of c,c++,c#,java,objective-c,sql,oracle,cobol - in other words learn the fundamental principles that tie all programming languages together without going too deep in any particular language. Someone has told me that most of the time as a programmer you won't be writing any code, but instead maintaing and existing code that people before you have built. Does that mean I don't really need to master any specific language and as long as I have general concepts it'll be good enough? If you or if you know someone who has worked in the financial industry as a software developer could you please share the experience and what is the daily routine consists of? Also what should I be learning right now while I am still young and in college? Do I have to thoroughly understand the market and the current economy? What about Oracle or SQL Databases - do I need to know them inside out as a programmer? Thanks if you have anything else to add that I have not mentioned then please do so! Thanks in advance!

    Read the article

  • How to translate this 2 queries from Mysql to Postgresql? :

    - by xRobot
    How can I translate this 2 queries in postgresql ? : CREATE TABLE `example` ( `id` int(10) unsigned NOT NULL auto_increment, `from` varchar(255) NOT NULL default '0', `message` text NOT NULL, `lastactivity` timestamp NULL default '0000-00-00 00:00:00', `read` int(10) unsigned NOT NULL, PRIMARY KEY (`id`), KEY `from` (`from`) ) DEFAULT CHARSET=utf8; Query: SELECT * FROM table_1 LEFT OUTER JOIN table_2 ON ( table_1.id = table_2.id ) WHERE (table_1.lastactivity > NOW()-100);

    Read the article

  • Have 2 separate tables or an additional field in 1 table?

    - by hkansal
    Hello, I am making a small personal application regarding my trade of shares of various companies. The actions can be selling shares of a company or buying. Therefore, the details to be saved in both cases would be: Number of Shares Average Price Would it be better to use a separate tables for "buy" and "sell" or just use one table for "trade" and keep a field that demarcates "buy" from "sell"?

    Read the article

  • node.js storing gamestate, how?

    - by expressnoob
    I'm writing a game in javascript, and to prevent cheating, i'm having the game be played on the server (it's a board game like a more complicated checkers). Since the game is fairly complex, I need to store the gamestate in order to validate client actions. Is it possible to store the gamestate in memory? Is that smart? Should I do that? If so, how? I don't know how that would work. I can also store in redis. And that sort of thing is pretty familiar to me and requires no explanation. But if I do store in redis, the problem is that on every single move, the game would need to get the data from redis and interpret and parse that data in order to recreate the gamestate from scratch. But since moves happen very frequently this seems very stupid to me. What should I do?

    Read the article

  • SQL Server 2005: Rename DB Server Instance Name?

    - by Code Sherpa
    Hi, Can somebody tell me how to rename the DB server instance name and a DB name in SQL Server 2005? Right Now I Have SERVER/OLDNAME -- oldnameDB I want to change the server instance and also change the db name. I have tried: EXEC sp_renamedb 'oldName', 'newName' and that has changed the dbname as it appers in the tree directory. But, when I do "select @@servername" it is the old name. Also, the MDF and LDF files are still the old name. How do change instance and db names as a clean sweep across the server? Thanks.

    Read the article

  • What's the steps for SQL optimization and changes without reflect live system ?

    - by Space Cracker
    we have a big portal that build using SharePoint 2007 , asp.net 3.5 , SQL Server 2005 .. many developers work in it since 01/2008 and we are now doing huge analysis for current SQL Databases [not share-point DB ] to optimize and enhance it. The main db have about 330 table and 1720 stored procedure (SP) created from 01/2008 till now Many table names / Columns is very long and we want to short it we found SP names is written in 25 format :( , some of them are very complex and also we want to rename many SP parameters need to be renamed one of the biggest table is Registered user table, that will be spitted in more than one table for some optimization, many columns name will be changed I searched for the way that i can rename table names ,columns and i found SQL refactor tool but i still trying it .. my questions : Is SQl Refactor is the best tool for renaming ? or is there any other one ? if i want to make it manually, is there any references or best practice for that ? How can i do such changes in fast and stable way .. i search for recommendations and case studies if exist ?

    Read the article

  • How can an improvement to the query cache be tracked?

    - by Bill Paetzke
    I am parameterizing my web app's ad hoc sql. As a result, I expect the query plan cache to reduce in size and have a higher hit ratio. Perhaps even other important metrics will be improved. Could I use perfmon to track this? If so, what counters should I use? If not perfmon, how could I report on the impact of this change?

    Read the article

  • Embedded analog of CouchDB, same as sqlite for SQL Server

    - by Mike Chaliy
    I like an idea of document oriented databases like CouchDB. I am looking for simple analog. My requirements is just: persistance storage for schema less data; some simple in-proc quering; good to have transactions and versioning; ruby API; map/reduce is aslo good to have; should work on shared hosting What I do not need is REST/HTTP interfaces (I will use it in-proc). Also I do not need all scalability stuff.

    Read the article

  • What type of data store should I use for my ios app?

    - by mwiederrecht
    I am pretty new to ios and using servers so forgive me. I am building an ios app for research. I need to monitor things that the user does and then push it up to a server for analysis (yes, with user and IRB permission). On the client's side I need to keep quite a bit of data that won't really change except in the case of pulling an updated version from the server, and then a minimal amount of user-specific data. Most of the data I will collect needs to be pushed to a server for analysis and then can be deleted from the client side. I am struggling to figure out what kind of data store I need to use, especially since I am not quite sure how the pushing and pulling from the server process works yet. Does it make sense to use Core Data? XML? SQLite? I like the Core Data idea, but I am not sure what kind of problems I will run into when I need to send large amounts of data to it and from it from the server. I imagine I might need to send data in a different form than it is probably stored in on either end - so what kind of overhead am I likely to run into in the process of converting that data? Is there a good format to save stuff in that would work well for me on both ends AND for sending the data? As you can probably tell, I could use some advice. Thanks!

    Read the article

  • Regarding data storage in ecommerce applications

    - by geeth
    Why is MainFrame better choice to stores data related to customer, orders etc? I work with a online retail store, they use .net technologies for applications and MainFrames for storing product, customer, order etc related data. Is SQL DB server not a good option for these type of applications? How is MainFrames better choice than SQL DB? Please provide your insight.

    Read the article

  • getting smallest of coordinates that differ by N or more in Python

    - by user248237
    suppose I have a list of coordinates: data = [[(10, 20), (100, 120), (0, 5), (50, 60)], [(13, 20), (300, 400), (100, 120), (51, 62)]] and I want to take all tuples that either appear in each list in data, or any tuple that differs from all tuples in lists other than its own by 3 or less. How can I do this efficiently in Python? For the above example, the results should be: [[(100, 120), # since it occurs in both lists (10, 20), (13, 20), # since they differ by only 3 (50, 60), (51, 60)]] (0, 5) and (300, 400) would not be included, since they don't appear in both lists and are not different from elements in lists other than their own by 3 or less. how can this be computed? thanks.

    Read the article

  • Multiple column foreign key contraints

    - by eugene4968
    I want to setup table constraints for the following scenario and I’m not sure how to do it or if it’s even possible in SQL Server 2005. I have three tables A,B,C. C is a child of B. B will have a optional foreign key(may be null) referencing A. For performance reasons I also want table C to have the same foreign key reference to table A. The constraint on table C should be that C must reference its parent (B) and also have the same foreign key reference to A as its parent. Anyone have any thoughts on how to do this?

    Read the article

  • Most efficient way to maintain a 'set' in SQL Server?

    - by SEVEN YEAR LIBERAL ARTS DEGREE
    I have ~2 million rows or so of data, each row with an artificial PK, and two Id fields (so: PK, ID1, ID2). I have a unique constraint (and index) on ID1+ID2. I get two sorts of updates, both with a distinct ID1 per update. 100-1000 rows of all-new data (ID1 is new) 100-1000 rows of largely, but not necessarily completely overlapping data (ID1 already exists, maybe new ID1+ID2 pairs) What's the most efficient way to maintain this 'set'? Here are the options as I see them: Delete all the rows with ID1, insert all the new rows (yikes) Query all the existing rows from the set of new data ID1+ID2, only insert the new rows Insert all the new rows, ignore inserts that trigger unique constraint violations Any thoughts?

    Read the article

  • SQL Server: compare columns in two tables.

    - by maxt3r
    Hi, I've recently done a migration from a really old version of some application to the current version and i faced some problems while migrating databases. I need a query that could help me to compare columns in two tables. I mean not the data in rows, I need to compare the columns itself to figure out, what changes in table structure I've missed.

    Read the article

  • What's the most simple way to retrieve all data from a table and save it back in .NET 3.5?

    - by zoman
    I have a number of tables containing some basic (business related) mapping data. What's the most simple way to load the data from those tables, then save the modified values back. (all data should be replaced in the tables) An ORM is out of question as I would like to avoid creating domain objects for each table. The actual editing of the data is not an issue. (it is exported into Excel where the data is edited, then the file is uploaded with the modified data) The technology is .NET 3.5 (ASP.NET MVC) and SQL Server 2005. Thanks.

    Read the article

< Previous Page | 500 501 502 503 504 505 506 507 508 509 510 511  | Next Page >