Search Results

Search found 34962 results on 1399 pages for 'drop database'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 344/1399 | < Previous Page | 340 341 342 343 344 345 346 347 348 349 350 351  | Next Page >

  • Composite Primary and Cardinality

    - by srini.venigalla
    I have some questions on Composite Primary Keys and the cardinality of the columns. I searched the web, but did not find any definitive answer, so I am trying again. The questions are: Context: Large (50M - 500M rows) OLAP Prep tables, not NOSQL, not Columnar. MySQL and DB2 1) Does the order of keys in a PK matter? 2) If the cardinality of the columns varies heavily, which should be used first. For example, if I have CLIENT/CAMPAIGN/PROGRAM where CLIENT is highly cardinal, CAMPAIGN is moderate, PROGRAM is almost like a bitmap index, what order is the best? 3) What order is the best for Join, if there is a Where clause and when there is no Where Clause (for views) Thanks in advance.

    Read the article

  • MySQL Throws NullReferenceException in Finalize... How are you coping with this?

    - by Cyril Gupta
    I am using MySQL with the .Net connector on 64 bit Windows. For some reason Mysql is throwing a NullReferenceException in Finalize. This is the problem here and it seems that its due to a bug described here. This bug was reported in 6.22, but I am getting the issue with 6.23 too so apparently it is not fixed. I am using MySQL both with the helper classes, and by instantiating the connection and the Mysqlcommand object. Does anybody have any idea what part of my code do I need to change to fix this issue? Cause even though this is a bug in Mysql this is not universal because I am not getting the problem in my other projects. MySQL bug report has no details on how to reproduce it either. Any suggestions?

    Read the article

  • Porting Oracle Date Manipulation

    - by Grasper
    I need to port this following from Oracle syntax to Postgresql. Both FLO_END_DT and FLO_START_DATE are of type DATE in Oracle, and TIMESTAMP WITHOUT TIME ZONE in Postgresql: SELECT TRUNC( TO_CHAR(ROUND(( FL.FLO_END_DT- FL.FLO_START_DT)* 24), '9999D99'),2) FROM FLOWS FL I am not familiar enough with Oracle to know what it is trying to accomplish. Any ideas?

    Read the article

  • How to point to other table's ID with hibernate?

    - by Wilhelm
    The problem: let's say I have two tables Client, and Product, in which Client has its primary key and a column called products (that points to pk's in Product table)... ok, if I need products to point only one row, it's nice, but if I need it to point for... 1000 rows in Product table, the products column would have to be larger enought... but I can't predict this situation. So, how could I design my table and how would I use hibernate with it, to achieve that "pointing" in a optmized and maybe "easy" way. NOTE: I excluded some columns of the "design" presented here, just to keep the simplicity.

    Read the article

  • Growing MS Access File Size problem

    - by user55886
    I have a large MS Access application with a lot of computations in VBA code. When I run it it eventually crashes due to excessive file size. There are a lot of intermediate tables and queries created and subsequently deleted, but Access does not reclaim the space. I have diligently closed all intermediate record sets and set all temporary objects to nothing, but nothing helps. The only way I can get my code to run is to run part of it, stop and repair/compress the file then restart the code. Isn't there a better way? Thanks

    Read the article

  • How many colunms in table to keep? - MySQL

    - by Dennis
    I am stuck between row vs colunms table design for storing some items but the decision is which table is easier to manage and if colunms then how many colunms are best to have? For example I have object meta data, ideally there are 45 pieces of information (after being normalized) on the same level that i need to store per object. So is 45 colunms in a heavry read/write table good? Can it work flawless in a real world situation of heavy concurrent read/writes?

    Read the article

  • How to access data using VBSCRIPT from a stored procedure which contains values in Temp table ?

    - by Srivigneshwar
    Hi , for testing purpose I wrote a VBscript which will fetch values from Sybase by executing a stored procedure which contains values in temp table. When I run the script I get the following errors , "Either BOF or EOF is True, or the current record has been deleted. Requested operation requires a current record." or "Item cannot be found in the collection corresponding to the requested name or ordinal." Somewhere when I was googling I found that , the above error message will be shown when we use temp table in stored procedure, if that is the reason , then how can I access data via VBscript by executing the stored procedure ??

    Read the article

  • iPhone Core Data - Access deep attributes with to many relationships

    - by ncohen
    Hi everyone, Let say I have an entity user which has a one to many relationship with the entity menu which has a one to many relationship with the entity meal which has a many to one relationship with the entity recipe which has a one to many relationship with the entity element. What I would like to do is to select the elements which belong to a particular user (username = myUsername) and particular menu*s* (minDate < menu.date < maxDate). Does anyone have an idea how to get them? Thanks

    Read the article

  • Scalable way of doing self join with many to many table

    - by johnathan
    I have a table structure like the following: user id name profile_stat id name profile_stat_value id name user_profile user_id profile_stat_id profile_stat_value_id My question is: How do I evaluate a query where I want to find all users with profile_stat_id and profile_stat_value_id for many stats? I've tried doing an inner self join, but that quickly gets crazy when searching for many stats. I've also tried doing a count on the actual user_profile table, and that's much better, but still slow. Is there some magic I'm missing? I have about 10 million rows in the user_profile table and want the query to take no longer than a few seconds. Is that possible?

    Read the article

  • Adding Postgres table cells based on same value

    - by russell kinch
    I have a table called expenses. There are numerous columns but the ones involved in my php page are date, spplierinv, amount. I have created a page that lists all the expenses in a given month and totals it at the end. However, each row has a value, but many rows might be on the same supplier invoice.This means adding each row with the same supplierinv to get a total as per my bank statement. Is there anyway I can get a total for the rows based on the supplierinv. I mean say I have 10 rows. 5 on supplierinv 4, two on supplierinv 5 and 3 on supplierinv 12, how can a get 3 figures (inv 4, 5 and 12) and the grand total at the bottom. Many thanks

    Read the article

  • Challege: merging csv files intelligently!

    - by Evenz495
    We are in the middle of changing web store platform and we need to import products' data from different sources. We currently have several different csv files from different it systems/databases because each system is missing some information. Fortunatly the product ids are the same so it's possible to relate the data using ids. We need to merge this data into one big csv file so we can import in into our new e-commerce site. My question: is there a general approach when you need to merge csv files with related data into one csv file? Are there any applications or tools that helps you out?

    Read the article

  • IF I have multiple candidate keys which one is a primary key and justify your choice ??

    - by zahrani
    Given R = { Account , Analyst , Assets, Broker, Client, Commission, Company, Dividend, Exchange, Investment, Office, Profile, Return, Risk_profile, Stock, Volume} and a set of functional dependencies F{fd1, fd2,fd3, fd4, fd5,fd6, fd7, fd8, fd9, fd10, fd11} where: fd1: Client - Office fd2: Stock - Exchange, Dividend fd3: Broker - Profile fd4: Company - Stock fd5: Client - Risk_profile, Analyst fd6: Analyst - Broker fd7: Stock, Broker - Invenstment, Volume fd8: Stock - Company fd9: Investment,Commission - Return fd10: Stock, Broker - Client fd11: Account - Assests these are candidate key(s) : (Account, Commission,Analyst ,Company) (Account, Commission,Analyst ,Stock) (Account ,Commission,Broker ,Company) (Account ,Commission,Broker ,Stock) (Account ,Commission,Client, Company) (Account ,Commission,Client ,Stock) (Q) Select a primary key and justify your choice ? I was select (Account ,Commission,Broker ,Stock) as a primary key ??? I chose that because it has the most direct dependencies compared to other ones. e.g. more attributes are functionally dependent on this primary key. please check if my answer is it true ? or Not I'm waiting your answer asap thank you

    Read the article

  • large databases in sqlite - file size considerations?

    - by Gj
    I'm using a sqlite db which is very convenient and seems to meet all of my needs at this point. Currently my db size is <50MB, but I now need to add a new table which will store large text blobs, which will cause the db to reach up to 5GB within the next year. Would sqlite be able to deal with a 5GB db size? Any caveats to that, compared with say mysql?

    Read the article

  • Multi join query returns to many results and improperly matched

    - by Woot4Moo
    I have the following minimal schema in Oracle: http://sqlfiddle.com/#!4/c1ed0/14 The queries I have run yield too many results and this query: select cat.*, status.*, source.* from cats cat, status status, source source Left OUTER JOIN source source2 on source2.sourceid = 1 Right OUTER JOIN status status2 on status2.isStray =0 order by cat.name will yield incorrect results. What I am expecting is a table that looks like the following however I cannot seem to come up with the correct SQL. NAME AGE LENGTH STATUSID CATSOURCE ISSTRAY SOURCEID CATID Adam 1 25 null null null 1 2 Bill 5 1 null null null null null Charles 7 5 null null null null null Steve 12 15 1 1 1 1 1 In plain English what I am looking for is to return all known cats + their associated cat source + their cat status while retaining null values. The only information I will have is the source that I am curious about. I also only want the cats that have a status of either STRAY or UNKNOWN (null)

    Read the article

  • Decimal rounding strategies in enterprise applications

    - by Sapphire
    Well, I am wondering about a thing with rounding decimals, and storing them in DB. Problem is like this: Let's say we have a customer and a invoice. The invoice has total price of $100.495 (due to some discount percentage which is not integer number), but it is shown as $100.50 (when rounded, just for print on invoice). It is stored in the DB with the price of $100.495, which means that when customer makes a deposit of $100.50 it will have $0.005 extra on the account. If this is rounded, it will appear as $0, but after couple of invoices it would keep accumulating, which would appear wrong (although it actually is not). What is best to do in this case. Store the value of $100.50, or leave everything as-is?

    Read the article

  • How to build a SQL statement when any combination of user input to the table is possible?

    - by Greg McNulty
    Example: the user fills in everything but the product name. I need to search on what is supplied, so in this case everything but productName= This example could be for any combination of input. Is there a way to do this? Thanks. $name = $_POST['n']; $cat = $_POST['c']; $price = $_POST['p']; if( !($name) ) { $name = some character to select all? } $sql = "SELECT * FROM products WHERE productCategory='$cat' and productName='$name' and productPrice='$price' "; EDIT Solution does not have to protect from attacks. Specifically looking at the dynamic part of it.

    Read the article

  • Rails - Scalable calculation model

    - by H O
    I currently have a calculation structure in my rails app that has models metric, operand and operation_type. Presently, the metric model has many operands, and can perform calculations based on the operation_type (e.g. sum, multiply, etc.), and each operand is defined as being right or left (i.e. so that if the operation is division, the numerator and denominator can be identified). Presently, an operand is always an attribute of some model, e.g. @customer.sales.selling_price.sum. In order to make this scalable, in need to allow an operand to be either an attribute of some kind, or the results of a previous operation, i.e. an operand can be a metric. I have included a diagram of how my models currently look: Can anyone assist me with the most elegant way of allowing an operand to be an actual operand, or another metric? Thanks! EDIT: It seems based on the only answer so far that perhaps polymorphic associations are the way to go on this, but the answer is so brief I have no idea how they could be used in this way - can anyone elaborate? EDIT 2: OK, I think I'm getting somewhere - essentially i presently have a metric, which has_many operands, and an operand has_many metrics. I need a polymorphic self join, where a metric can also have many metrics - do I need to call this something else, perhaps calculated_metrics, so that the metric model can use itself? That would leave me with a situation where a metric has_many operands, and a metric has many calculated_metrics.

    Read the article

  • Sencha : how to pass parameter to php using Ext.data.HttpProxy?

    - by Lauraire Jérémy
    I have successfully completed this great tutorial : http://www.sencha.com/learn/ext-js-grids-with-php-and-sql/ I just can't use the baseParams field specified with the proxy... Here is my code that follows tutorial description : __ My Store : Communes.js ____ Ext.define('app.store.Communes', { extend: 'Ext.data.Store', id: 'communesstore', requires: ['app.model.Commune'], config: { model: 'app.model.Commune', departement:'var', // the proxy with POST method proxy: new Ext.data.HttpProxy({ url: 'app/php/communes.php', // File to connect to method: 'POST' }), // the parameter passed to the proxy baseParams:{ departement: "VAR" }, // the JSON parser reader: new Ext.data.JsonReader({ // we tell the datastore where to get his data from rootProperty: 'results' }, [ { name: 'IdCommune', type: 'integer' }, { name: 'NomCommune', type: 'string' } ]), autoLoad: true, sortInfo:{ field: 'IdCommune', direction: "ASC" } } }); _____ The php file : communes.php _____ <?php /** * CREATE THE CONNECTION */ mysql_connect("localhost", "root", "pwd") or die("Could not connect: " . mysql_error()); mysql_select_db("databasename"); /** * INITIATE THE POST */ $departement = 'null'; if ( isset($_POST['departement'])){ $departement = $_POST['departement']; // Get this from Ext } getListCommunes($departement); /** * */ function getListCommunes($departement) { [CODE HERE WORK FINE : just a connection and query but $departement is NULL] } ?> There is no parameter passed as POST method... Any idea?

    Read the article

  • iPhone - Create non-persistent entities in core data

    - by ncohen
    Hi everyone, I would like to use entity objects but not store them... I read that I could create them like this: myElement = (Element *)[NSEntityDescription insertNewObjectForEntityForName:@"Element" inManagedObjectContext:managedObjectContext]; And right after that remove them: [managedObjectContext deleteObject:myElement]; then I can use my elements: myElement.property1 = @"Hello"; This works pretty well even though I think this is probably not the most optimal way to do it... Then I try to use it in my UITableView... the problem is that the object get released after the initialization. My table becomes empty when I move it! Thanks edit: I've also tried to copy the element ([myElement copy]) but I get an error...

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 340 341 342 343 344 345 346 347 348 349 350 351  | Next Page >