My knowledge of MySQL is not very in depth. If I have two tables that for example look like this: Table1 Date v1 v2 v3 05/01/2010 26 abc 45 05/02/2010 31 def 25 05/03/2010 50 ghi 46 Table2 Date v1 v2 v3 05/01/2010 42 jkl 15 05/02/2010 28 mno 14 05/03/2010 12 pqr 64 How can I join them in a query by their dat...
I am looking to do the following using an NHibernate Criteria Query I have "Product"s which has 0 to Many "Media"s A product can be associated with 1 to Many ProductCategories These use a table in the middled to create the join ProductCategories Id Title ProductsProductCategories ProductCategoryId ProductId Produ...
Hi, I have the following 2 tables: items: id int primary key bla text events: id_items int num int when timestamp without time zone ble text composite primary key: id_items, num and want to select to each item the most recent event (the newest 'when'). I wrote an request, but I don't know if it could be written more efficient...
Hi Guys, This is probably incredibly simple, but I just cant see the wood for the trees at the moment. For brevity, I would like to model a word object, that has related words to it (synonyms), In doing so I could have the following mappings: <class name="Word" table="bs_word"> <id name="Id" column="WordId" type="Int32" unsaved-value=...
What is the difference between between Left Join and Left Outer Join? ...
Hello, The query below works well. It pulls data from two MySQL tables, "submission" and "login." I would like to also pull data from a third table called "comment" in the same database. The table "comment" has the following fields: commentid, loginid, submissionid, comment, datecommented Two of the fields in the table "login" a...
I have two tables which get updated at almost the exact same time - I need to join on the datetime column. I've tried this: SELECT * FROM A, B WHERE ABS(DATEDIFF(second, A.Date_Time, B.Date_Time)) = ( SELECT MIN(ABS(DATEDIFF(second, A.Date_Time, B2.Date_Time))) FROM B AS B2 ) But it tells me: Multiple columns are specifie...
Hi, I am evaluating Microstrategy 9.0.1 and attempting to build a prototype metadata layer using its Architect tool. The tool doesn't seem to have any specific means to mark up joins in the way that the editing tools for SSRS data source views or Business Objects universes do. How does this work in Microstrategy - I have never used t...
I have a varchar field that contains a string like "10,11,12,13". How can I use that CSV string to join to another table with those IDs? Here's the approach I'm taking now: select * from SomeTable a WHERE (',' + @csvString + ',') LIKE '%,' + CONVERT(varchar(25), a.ID) + ',%' Where @csvString is "10,11,12,...". I intend to use this ...
I try to implement Hash join in Hadoop. However, Hadoop seems to have already a map-side join and a reduce - side join already implemented. What is the difference between these techniques and hash join? ...
Hello, I'll attempt to make my question as clear as possible. I'm fairly unexperienced with SQL, only know the really basic queries. In order to have a better idea I'd been reading the MySQL manual for the past few days, but I couldn't really find a concrete solution and my needs are quite specific. I've got 3 MySQL MyISAM tables: table...
Hi We are developing something like a social networking website. I've got task to do 'follow me' functionality. In our website objects are users, teams, companies, channels and groups (please don't ask why there are groups and teams - it is complicated for me too, but teams are releated to user's talent) Users, teams, channels, compani...
I have 4 tables. r1, r2, r3 and r4. The table columns are the following: rId | rName I want to have, in fine, an unique table - let's call it R. Obviously, R will have the following structure: rTableName | rId | rName I'm looking for a solution, and the more natural for me is to: add a single column to all rX insert this column...
I need to be able to do the following: Select * from Table1 left join Table2 on id1 = id2 AND i1 = ? Hibernate criteria doesn't allow be to specify the i1 = ? part. The existing code is using hibernate criteria and it would be a huge refactor to swap out for HQL Does anybody have any tips how I could implement this differently or ...
Hi all! I'm working on a small project in regards of the upcoming World Cup. I'm building a roster/leaderboard/scoredboard based on groups with national teams. The idea is to have information on all upcoming matches within the group or in the knockout phase (scores, time of the match, match stats etc.). Currently I'm stuck with the DB in...
I've looked all over and haven't yet found an intelligent way to handle this, though I feel sure one is possible: One table of historical data has quarterly information: CREATE TABLE Quarterly ( unique_ID INT UNSIGNED NOT NULL, date_posted DATE NOT NULL, datasource TINYINT UNSIGNED NOT NULL, data FLOAT NOT NULL, PRIMARY KEY (unique_ID)...
Is there a way to specify a join on all fields from table A with only one field from table B? Is it necessary to specify each individual field from each table instead of using the all symbol (*) for one of the tables? ...
What is the difference between the SQL keywords union and join? ...
i got three tables CATS id name ------------------------------ 1 category1 2 category2 3 category3 4 category4 PRODUCT id name ------------------------------ 1 product1 2 product2 ZW-CAT-PRODUCT id_cats id_product ---------------------------...
Hi: I have three tables: Suppliers, Parts and Types. I need to join all of them while discriminating columns with the same name (say, "id") in the three tables. I would like to successfully run this query: CREATE VIEW Everything AS SELECT Suppliers.name as supplier, Parts.id, Parts.description, Types.typedesc as...