left-join

问题 In postgresql I can use subquery in join condition SELECT * FROM table1 LEFT JOIN table2 ON table1.id1 = (SELECT id2 FROM table2 LIMIT 1); But when I try to use it in Access SELECT * FROM table1 LEFT JOIN table2 ON table1.id1 = (SELECT TOP 1 id2 FROM table2); I get syntax error. Is it actually impossible in Access or just my mistake? I know that I can get the same result with WHERE , but my question is about possibilities of JOIN in Access. 回答1: It's not possible, per the MSDN documentation:

问题 I have a Rails app running at Heroku, where I'm trying to calculate the rank (position) of a user to a highscore list. The app is a place for the users to bet each other and the can start the wager (be creating a CHOICE) or they can bet against an already created Choice (by making a BET). I have the following SQL which should give me an array of users based on their total winnings on both Choices and Bets.. But it's giving me some wrong total winning and I think the problem is in the Left

问题 I have a table named friends; friends id uid fid 1 1 2 (1 is a friend of 2 and vice versa) 2 1 3 (1 is a friend of 3 and vice versa) 3 4 1 (1 is a friend of 4 and vice versa) 4 5 1 (1 is a friend of 5 and vice versa) And a corresponding table for users; users uid name 1 mike 2 john 3 karl 4 mary 5 tony This doesn't seem to do the trick: SELECT name FROM users LEFT JOIN friends ON friends.uid=users.uid WHERE friends.uid='1' OR friends.fid='1' What should my query be to get all the names of

问题 i stack at mysql syntax where i have a table revenue with values title_id | revenue | cost 1 | 10 | 5 2 10 5 3 10 5 4 10 5 1 20 6 2 20 6 3 20 6 4 20 6 and then i have table fund with values title_id | interest 1 | 10 2 10 3 10 4 10 1 20 2 20 3 20 4 20 I want to join this two table using left join and rollup the values like this : SELECT R.title_id, R.revenue, R.cost, F.interest FROM (SELECT title_id, Sum(revenue) revenue, Sum(cost) cost FROM revenue GROUP BY revenue.title_id with rollup) r

问题 Suppose I have this model: class PhotoAlbum(models.Model): title = models.CharField(max_length=128) author = models.CharField(max_length=128) class Photo(models.Model): album = models.ForeignKey('PhotoAlbum') And I want to do this query: "Find 10 albums whose name starts with 'The', and then give me all the photos in those albums." In SQL I could do it something like this: SELECT * FROM (SELECT * FROM photoalbum WHERE title LIKE 'The%' LIMIT 10) AS selected_albums LEFT JOIN photo ON photo

问题 I´m using Mysql since quite a while and am really confused by the result of a simple LEFT JOIN on three Tables. I have the following three tables (I created an example, to narrow it down) a) persons +----------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+ | PersonID | int(11) | NO | PRI | NULL | auto_increment | | Name | varchar(50) | YES | | NULL | | | Age | int(11) |

问题 I have integrated Pentaho5 EE with Impala. In my schema dimension values are not gathered from the fact table as it is a huge table and it takes too long to calculate them. Since dimension values come dimension tables Mondrian compiles a query which does a join of dimension table with fact table in that order (i.e dimension table on the left). The query this way is slow and I read on the Cloudera website that if you do a join in Impala the bigger table (the fact table) has to be on the right.

问题 I have a problem. I have 4 tables: Invoice_Payment, Invoice, Client, and Calendar Basically, I have the below query, which works well, except, months with no date_due don't return. I.E only months with a date_due will be returned. Note: the calendar table simply lists every day of the year. It contains a single col call date_field Database: http://oberto.co.nz/jInvoice.txt Expected output: my current query, below, will return something like: month total August 5 September 0 October 196

问题 Let's say my DB Scheme is as follows: T_PRODUCT id_product (int, primary) two entries: (id_product =1) , (id_product =2) T_USER id_user (int, primary) id_product (int, foreign key) name_user (varchar) two entries: (id_product=1,name_user='John') , (id_product=1,name_user='Mike') If I run a first query to get all products with their users (if there are any), I get this: SELECT T_PRODUCT.id_product, T_USER.name_user FROM T_PRODUCT LEFT JOIN T_USER on T_USER.id_product = T_PRODUCT.id_product; >>

问题 Let's say my DB Scheme is as follows: T_PRODUCT id_product (int, primary) two entries: (id_product =1) , (id_product =2) T_USER id_user (int, primary) id_product (int, foreign key) name_user (varchar) two entries: (id_product=1,name_user='John') , (id_product=1,name_user='Mike') If I run a first query to get all products with their users (if there are any), I get this: SELECT T_PRODUCT.id_product, T_USER.name_user FROM T_PRODUCT LEFT JOIN T_USER on T_USER.id_product = T_PRODUCT.id_product; >>