Search Results

Search found 8603 results on 345 pages for 'altering tables'.

Page 246/345 | < Previous Page | 242 243 244 245 246 247 248 249 250 251 252 253  | Next Page >

  • Advanced queries in HBase

    - by Teflon Ted
    Given the following HBase schema scenario (from the official FAQ)... How would you design an Hbase table for many-to-many association between two entities, for example Student and Course? I would define two tables: Student: student id student data (name, address, ...) courses (use course ids as column qualifiers here) Course: course id course data (name, syllabus, ...) students (use student ids as column qualifiers here) This schema gives you fast access to the queries, show all classes for a student (student table, courses family), or all students for a class (courses table, students family). How would you satisfy the request: "Give me all the students that share at least two courses in common"? Can you build a "query" in HBase that will return that set, or do you have to retrieve all the pertinent data and crunch it yourself in code?

    Read the article

  • Custom OData operation / customize EF model to hide join table in many-to-many relationship

    - by AC
    I've got a data model that has two tables with a join table for a many to many relationship & creating an OData service to expose the data for CRUD ops in a Silverlight app. What I'd like to do is abstract the join table from the service. I'm not sure if the best way to do this would be in the model (using EF in .NET3.5SP1) or if I should do it with a custom service operation. If I do it in the EF model (not sure how I'd do this), then the OOTB WCF Data Service stuff would make it easy to say [..]/Courses(1)/Modules ... otherwise I'd have to create a custom operation to do this. Is it possible to do this in the EF model and if so, how does that work?

    Read the article

  • Java JPA @OneToMany neededs to reciprocate @ManyToOne?

    - by bguiz
    Create Table A ( ID varchar(8), Primary Key(ID) ); Create Table B ( ID varchar(8), A_ID varchar(8), Primary Key(ID), Foreign Key(A_ID) References A(ID) ); Given that I have created two tables using the SQL statements above, and I want to create Entity classes for them, for the class B, I have these member attributes: @Id @Column(name = "ID", nullable = false, length = 8) private String id; @JoinColumn(name = "A_ID", referencedColumnName = "ID", nullable = false) @ManyToOne(optional = false) private A AId; In class A, do I need to reciprocate the many-to-one relationship? @Id @Column(name = "ID", nullable = false, length = 8) private String id; @OneToMany(cascade = CascadeType.ALL, mappedBy = "AId") private List<B> BList; //<-- Is this attribute necessary? Is it a necessary or a good idea to have a reciprocal @OneToMany for the @ManyToOne? If I make the design decision to leave out the @OneToMany annotated attribute now, will come back to bite me further down.

    Read the article

  • Find Date From Non Contiguous Ranges

    - by AGoodDisplayName
    I am looking to find an best way to find a date from date ranges that may or may not be contiguous (I am trying to avoid a cursor, or a heavy function if possible). Lets say I have hotel guests that come and go (check in, check out). I want to find the date that a certain guest stayed their 45th night with us. The database we use records the data as so: Create Table #GuestLog( ClientId int, StartDate DateTime, EndDate DateTime) Here is some data Insert Into #GuestLog Values(1, '01/01/2010', '01/10/2010') Insert Into #GuestLog Values(1, '01/16/2010', '01/29/2010') Insert Into #GuestLog Values(1, '02/13/2010', '02/26/2010') Insert Into #GuestLog Values(1, '04/05/2010', '06/01/2010') Insert Into #GuestLog Values(1, '07/01/2010', '07/21/2010') So far I can only think of solutions that involve functions with temp tables and crazy stuff like that, I feel like I'm over thinking it. Thanks ahead of time.

    Read the article

  • MySQL : delete from table that is used in the where clause

    - by Eric
    I am writing a small script to synchronize 2 MySQL tables ( t1 to be 'mirrored' to t2 ) In a step I would like to delete rows inside t2 that has been delete in t1 with the same id. I tried this query : delete from t2 where t2.id in ( select t2.id left join t1 on (t1.id=t2.id) where t1.id is null ) But Mysql forbid me to use t2 in the same time in the delete and in the select (sound logical by the way) Of course, I can split the query into 2 queries : first select IDs, then delete rows with these IDs. My question : do you have a cleaner way to delete row from t2 that does not exist anymore in t1 ? with one query only ?

    Read the article

  • Ideas for loading initial data in an iPhone application?

    - by Derek Clarkson
    Hi all, In my app I want to load some initial data to show the user how it works. The app uses a CoreData managed sqllite db. SO far I've thought of 3 options: Write code into a class to programmatically create the data. Create a xml file in the apps resources and load through a NSXmlParser whose delegate creates the entries in the sqllite db. Same as option #2, but use a json file and bring in a 3rd party lib to read it. Are there other options I have not found yet? and given that I'm talking about perhaps 6 records per table when there are 3 tables, which would you choose?

    Read the article

  • MySQL Query, how to group and count in one row ?

    - by Akarun
    Hi All, To simplify, I have tree tables: products, products-vs-orders, orders products fields : 'ProductID', 'Name', 'isGratis', ... products-vs-orders fields : 'ProductID', 'OrderID' orders fields : 'OrderID', 'Title', ... Actually, I have a query like this: SELECT orders.OrderID, orders.Title, COUNT(`products`.`isGratis`) AS "Quantity", `products`.`isGratis` FROM `orders`, `products-vs-orders`, `products` WHERE `orders`.`OrderID` = `products-vs-orders`.`OrderID` AND `products-vs-orders`.`ProductID` = `products`.`ProductID` GROUP BY `products`.`PackID`, `products`.`isGratis` This query works and return this surch of result: OrderID, Title, Quantity, isGratis 1 My Order 20 0 1 My Order 3 1 2 An other 8 0 2 An other 1 1 How can I retrieve the count of products 'gratis' and 'paid' in to separate cols ? OrderID, Title, Qt Paid, Qt Gratis 1 My Order 20 3 2 An other 8 1 Thanks for your help

    Read the article

  • Multiple foreign keys from one table linking to single primary key in second table

    - by croker10
    Hi all, I have a database with three tables, a household table, an adults table and a users table. The Household table contains two foreign keys, iAdult1ID and iAdult2ID. The Users table has a iUserID primary key and the Adult table has a corresponding iUserID foreign key. One of the columns in the Users table is strUsername, an e-mail address. I am trying to write a query that will allow me to search for an e-mail address for either adult that has a relation to the household. So I have two questions, assuming that all the values are not null, how can I do this? And two, in reality, iAdult2ID can be null, is it still possible to write a query to do this? Thanks for your help. Let me know if you need any more information.

    Read the article

  • mysql boolean joins

    - by user280381
    I want to use a JOIN to return a boolean result. Here's an example of the data... t1 id | data | 1 | abcd | 2 | 2425 | 3 | xyz | t2 id | data | t1_id | 1 | 75 | 2 | 2 | 79 | 2 | 3 | 45 | 3 | So with these two tables I want to select all the data from t1, and also whether a given variable appears in t2.data for each id. So say the variable is 79, the results should be id | data | t2_boolean 1 | abcd | 0 2 | abcd | 1 3 | xyz | 0 So I'm thinking some sort of join is needed, but without a WHERE clause. I've been banging my head about this one. Is it possible? I really need it inside the same statement as I want to sort results by the boolean field. As the boolean needs to be a field, can I put a join inside of a field? Thanks...

    Read the article

  • concatenate multi values in one record without duplication

    - by mikehjun
    I have a dbf table like below which is the result of one to many join from two tables. I want to have unique zone values from one Taxlot id field. table name: input table tid ----- zone 1 ------ A 1 ------ A 1 ------ B 1 ------ C 2 ------ D 2 ------ E 3 ------ C Desirable output table table name: input table tid ----- zone 1 ------ A, B, C 2 ------ D, E 3 ------ C I got some help but couldn't make it to work. inputTbl = r"C:\temp\input.dbf" taxIdZoningDict = {} searchRows = gp.searchcursor(inputTbl) searchRow = searchRows.next() while searchRow: if searchRow.TID in taxIdZoningDict: taxIdZoningDict[searchRow.TID].add(searchRow.ZONE) else: taxIdZoningDict[searchRow.TID] = set() #a set prevents dulpicates! taxIdZoningDict[searchRow.TID].add(searchRow.ZONE) searchRow = searchRows.next() outputTbl = r"C:\temp\output.dbf" gp.CreateTable_management(r"C:\temp", "output.dbf") gp.AddField_management(outputTbl, "TID", "LONG") gp.AddField_management(outputTbl, "ZONES", "TEXT", "", "", "20") tidList = taxIdZoningDict.keys() tidList.sort() #sorts in ascending order insertRows = gp.insertcursor(outputTbl) for tid in tidList: concatString = "" for zone in taxIdZoningDict[tid] concatString = concatString + zone + "," insertRow = insertRows.newrow() insertRow.TID = tid insertRow.ZONES = concatString[:-1] insertRows.insertrow(insertRow) del insertRow del insertRows

    Read the article

  • making sure "expiration_date - X" falls on a valid "date_of_price" (if not, use the next valid date_

    - by bobbyh
    I have two tables. The first table has two columns: ID and date_of_price. The date_of_price field skips weekend days and bank holidays when markets are closed. table: trading_dates ID date_of_price 1 8/7/2008 2 8/8/2008 3 8/11/2008 4 8/12/2008 The second table also has two columns: ID and expiration_date. The expiration_date field is the one day in each month when options expire. table: expiration_dates ID expiration_date 1 9/20/2008 2 10/18/2008 3 11/22/2008 I would like to do a query that subtracts a certain number of days from the expiration dates, with the caveat that the resulting date must be a valid date_of_price. If not, then the result should be the next valid date_of_price. For instance, say we are subtracting 41 days from the expiration_date. 41 days prior to 9/20/2008 is 8/10/2008. Since 8/10/2008 is not a valid date_of_price, we have to skip 8/10/2008. The query should return 8/11/2008, which is the next valid date_of_price. Any advice would be appreciated! :-)

    Read the article

  • 2 Select or 1 Join query ?

    - by xRobot
    I have 2 tables: book ( id, title, age ) ---- 100 milions of rows author ( id, book_id, name, born ) ---- 10 millions of rows Now, supposing I have a generic id of a book. I need to print this page: Title: mybook authors: Tom, Graham, Luis, Clarke, George So... what is the best way to do this ? 1) Simple join like this: Select book.title, author.name From book, author WHERE ( author.book_id = book.id ) AND ( book.id = 342 ) 2) For avoid the join, I could make 2 simple query: Select title FROM book WHERE id = 342 Select name FROM author WHERE book_id = 342 What is the most efficient way ?

    Read the article

  • MySQL - Join as zero if record Not IN

    - by Zurahn
    To explain by example, take two tables, A and B Table A id foo 1 x 2 y 3 z Table B id aid bar 1 3 50 2 1 100 An example join SELECT foo, bar FROM a, b WHERE a.id = b.aid; Garners a result of foo bar z 50 x 100 What I would like to do is get all values of foo and for any instances where there isn't a corresponding bar value, return 0 for that column. My best guess was something along the lines of SELECT foo, bar AS br FROM a, b WHERE a.id = b.aid OR a.id NOT IN (SELECT aid FROM b); But that returns duplicates and non-zero values for bar. Possible?

    Read the article

  • Best means to store data locally when offline

    - by mickartz
    I am in the midst of writing a small program (more to experiment with vs 2010 than anything else) Despite being an experiment it has some practical use for our local athletics club. My thought was to access the DB (currently online) to download the current members and store locally on a laptop (this is a MS sql table, used to power the club's website). take the laptop to the event (yes there ARE places that don't have internet coverage), add members to that days race (also a row from a sql table (though no changes would be made to this), record results (new records in 3rd table) Once home, showered and within internet access again, upload/edit the tables as per the race results/member changes etc. So I was thinking i'd do something like write xml files locally with the data, including a field to indicate changes etc? If anyone can point me in a direction i would appreciate it...hell if anyone could tell me if this has a name, I'd appreciate it.

    Read the article

  • Data Warehouse: One Database or many?

    - by drrollins
    At my new company, they keep all data associated with the data warehouse, including import, staging, audit, dimension and fact tables, together in the same physical database. I've been a database developer for a number of years now and this consolidation of function and form seems counter to everything I know. It seems to make security, backup/restore and performance management issues more manually intensive. Is this something that is done in the industry? Are there substantial reasons for doing or not doing it? The platform is Netezza. The size is in terabytes, hundreds of millions of rows. What I'm looking to get from answers to this question is a solid understanding of how right or wrong this path is. From your experience, what are the issues I should be focused on arguing if this is a path that will cause trouble for us down the road. If it is no big deal, then I'd like to know that as well.

    Read the article

  • How do you manage your sqlserver database projects for new builds and migrations?

    - by Rory
    How do you manage your sql server database build/deploy/migrate for visual studio projects? We have a product that includes a reasonable database part (~100 tables, ~500 procs/functions/views), so we need to be able to deploy new databases of the current version as well as upgrade older databases up to the current version. Currently we maintain separate scripts for creation of new databases and migration between versions. Clearly not ideal, but how is anyone else dealing with this? This is complicated for us by having many customers who each have their own db instance, rather than say just having dev/test/live instances on our own web servers, but the processes around managing dev/test/live for others must be similar.

    Read the article

  • problem with Doctrine i18n in Symfony

    - by fayer
    i have table data i want to internationalize. i added this code in my schema.yml: I18n: fields: [name] and another table with a suffix "_translation" was created. the problem is that this table's id column is not auto-incremented. so when adding fixture data there will be a problem. i wonder if there is a way to make this column auto-incremented, or else i have to manually correct this for a lot of tables everytime i want to add fixture data. thanks.

    Read the article

  • Mysql_insert_id with Doctrine

    - by Industrial
    Hi! I have a couple of tables (mySQL) that i would like to update with the help of Doctrine. The products table id is auto-incrementing, and here's a brief description on what I would like to do: $prod = new Products(); $prod->type = '0'; $categ = new CategoriesToProducts(); $categ->cat = '111'; $categ->product = $prod->id; $conn = Doctrine_Manager::connection(); $conn->flush(); How can I do this while using flush? Using a regular save is an alternative, but there will be multiple transactions while doing such. I have tried to find a Mysql_insert_id version for doctrine, but without any luck. Thanks!

    Read the article

  • MySQL join headaches, please help!

    - by Andrew Heath
    Ok, I've hit the wall here and need some help. Sample tables are as follows: SCENARIO_NATIONS [scenID] [side] [nation] scen001 1 Germany scen001 2 Britain scen001 2 Canada SCENARIO_NEEDUNITS [scenID] [unitID] scen001 0001 scen001 0003 scen001 0107 scen001 0258 scen001 0759 UNIT_BASIC_DATA [unitID] [nation] [name] 0001 Germany Mortars 0003 Germany Infantry 0107 Britain Lt 0258 Britain Infantry 0759 Canada Kilted Yaksmen Goal: given a scenID, pull a list of units from the database sorted by side, nation, name. I can do everything except for the side inclusion with: SELECT scenario_needunits.scenID, unit_basic_data.nation, unit_basic_data.name FROM scenario_needunits LEFT OUTER JOIN unit_basic_data ON scenario_needunits.unitID=unit_basic_data.unitID WHERE scenario_needunits.scenID='scen001' ORDER BY unit_basic_data.nation ASC, unit_basic_data.name ASC I've tried just dropping the SCENARIO_NATIONS table in as a LEFT OUTER JOIN on scenID but what ends up happening is that ALL units come back with a side of 1 because that's always the first side listed for the scenID in the SCENARIO_NATIONS table. Conceptually, what I think needs to happen is SCENARIO_NATIONS must be joined to both the scenID (to restrict it to just that scenario) and to each unit's nation but I don't have any idea how to do that and my Google-fu is inadequate. :-/

    Read the article

  • Select all rows where there is not a specific value in a different table

    - by JMC Creative
    This is a wordpress installation, but I think the question is more of a general sql question. First off, my sql skills are not great (I don't even know if I'm following the correct format for illustrating the db). I've got two tables: wp_posts : ID (pk) | post_name | ... ---------------------------- 45 | "Hello" 91 | "Funny" 16 | "Wheat" wp_postmeta : post_id (fk) | meta_key | meta_value | ... ------------------------------------------------ 45 | "_edit_lock" | 5789789834 45 | "fizzbizz" | "foobar" 91 | "_something" | "teve" 16 | "_edit_lock" | 8798756 I would to select all rows in wp_posts where there is NO corresponding row in wp_postmeta where meta_key = "fizzbizz" I originally had this query, but someone pointed out that it would not retrive ID = '16' in the above case. How would I correctly write the query? $pageposts = $wpdb->get_results(" SELECT * FROM wp_posts p JOIN wp_postmeta m ON p.ID = m.post_id WHERE m.meta_key <> 'fizzbizz' ORDER BY p.post_date DESC; ");

    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 do I choose a database?

    - by liamzebedee
    I need a comparison table of some sort for database varieties (MySQL, SQLite etc.). I can't find one. My use case is, I am implementing storage of objects in a distributed hash table. I need a database solution that is: Fast for sorting Simplistic (no users, preferably no additional structures like multiple tables etc.) Concurrent (if possible) Multi-platform File based (not stored in memory primarily) Centralized I will be programming in Go. As I understand, I believe I need what is called a Document Orientated Database, because I am storing objects, identified by keys. EDIT: While I am implementing a DHT, I will also be storing metadata about the objects, such as access counts etc. It would also be preferable to have TLL (time to live)

    Read the article

  • sql combine two subqueries

    - by Claudiu
    I have two tables. Table A has an id column. Table B has an Aid column and a type column. Example data: A: id -- 1 2 B: Aid | type ----+----- 1 | 1 1 | 1 1 | 3 1 | 1 1 | 4 1 | 5 1 | 4 2 | 2 2 | 4 2 | 3 I want to get all the IDs from table A where there is a certain amount of type 1 and type 3 actions. My query looks like this: SELECT id FROM A WHERE (SELECT COUNT(type) FROM B WHERE B.Aid = A.id AND B.type = 1) = 3 AND (SELECT COUNT(type) FROM B WHERE B.Aid = A.id AND B.type = 3) = 1 so on the data above, just the id 1 should be returned. Can I combine the 2 subqueries somehow?

    Read the article

  • how to get xml html after transpose and databind()

    - by rlee923
    Hi. I have some code that uses xsl and xml. The Xml control is on the design page. The xml control id is xmlApplication The xmlstring is generated and xsl has the format with all the tables and cells etc. Here is a part of thecode of a page which generates the final product which shows the xml in a certain format. xmlApplication.Document = xmlDoc; xmlApplication.Transform = transApp; xmlApplication.DataBind(); I am guessing after xmlApplication.Databind(), xmlApplication will be converted into something that can be put inside . Is it possible to grab as a string? Please let me know if I have a wrong idea abut this. Thanks a lot.

    Read the article

  • MSSQL - Select one random record not showing duplicates

    - by Lukes123
    I have two tables, events and photos, which relate together via the 'Event_ID' column. I wish to select ONE random photo from each event and display them. How can I do this? I have the following which displays all the photos which are associated. How can I limit it to one per event? SELECT Photos.Photo_Id, Photos.Photo_Path, Photos.Event_Id, Events.Event_Title, Events.Event_StartDate, Events.Event_EndDate FROM Photos, Events WHERE Photos.Event_Id = Events.Event_Id AND Events.Event_EndDate < GETDATE() AND Events.Event_EndDate IS NOT NULL AND Events.Event_StartDate IS NOT NULL ORDER BY NEWID() Thanks Luke Stratton

    Read the article

< Previous Page | 242 243 244 245 246 247 248 249 250 251 252 253  | Next Page >