join

SQL Server Select Distinct

I want to write a query like this: For a table that has these columns: ColA ColB ColC, ColD select first(ColA, ColB, ColC, ColD) distinct(ColB, ColC) from table order by ColD The query is supposed to order the table by ColD, then group the results by the combination of ColB and ColC (they may have different data types) and returns the...

What is the best way to use MySQL full-text search with a self-join?

I want to do something like: select a.a_ft,count(b.a_ft) FROM row a JOIN row b on match a.a_ft against (b.b_ft). However, this isn't legal. Basically, I just want to look for similar phrases in my database. What is the easiest way to do this? ...

Mysql Left join with condition on column

Hi, can you help me with sql query? I have this problem: I have two tables "Join" table: Reservation_has_meal +----------------+ | id_reservation | | id_meal | | pieces | +----------------+ and table with data: Meal +-------------+ | id_meal | | name | +-------------+ Sample data for Meal: 1 | carrot...

MySQL AND alternative for each table in a join

I have a simple join in a query however I need to have a condition on both of the tables "confirmed='yes'" but if one of the tables doesn't have any that match the query returns with no rows. Database: .----------parties----------. | id - party_id - confirmed | |---------------------------| | 1 1 yes | | 1 2 ...

C# GroupJoin efficiency

without using GroupJoin: var playersDictionary = players.ToDictionary(player => player.Id, element => new PlayerDto { Rounds = new List<RoundDto>() }); foreach (var round in rounds) { PlayerDto playerDto; playersDictionary.TryGetValue(round.PlayerId, out playerDto); if (playerDto != null) { playerDto.Rounds...

Ruby on Rails updating join table records

Hey, I have two models Users and Roles. I have setup a many to many relationship between the two models and I have a joint table called roles_users. I have a form on a page with a list of roles which the user checks a checkbox and it posts to the controller which then updates the roles_users table. At the moment in my update method I...

MySQL, join one item to multiple items in a single query

Say I've got two tables. One contains a list of items, and one contains pictures of the items. Something like this: Items +----+---------+ | id | name | +----+---------+ | 1 | oranges | | 2 | apples | +----+---------+ Pictures +----+---------+ | id | item_id | +----+---------+ | 1 | 1 | | 2 | 2 | | 3 | 2 ...

joining two sets in LINQ

var setsA = new List<SetA> { new SetA { SsnA = "3450734507", name = "setA"}, new SetA { SsnA = "6833467788", name = "setA"}, new SetA { SsnA = "5452347787", name = "setA"}, new SetA { SsnA = "9345345345", name = "setA"}, }; var setsB = new List<SetB> { new SetB { SsnB = "5452347787" ,n...

SQL joins "going up" two tables

I'm trying to create a moderately complex query with joins: SELECT `history`.`id`, `parts`.`type_id`, `serialized_parts`.`serial`, `history_actions`.`action`, `history`.`date_added` FROM `history_actions`, `history` LEFT OUTER JOIN `parts` ON `parts`.`id` = `history`.`part_id` LEFT OUTER JOIN `serialized...

how can add an extra select in this query?

i've three tables related. images: id | filename | filesize | ... nodes: image_id | tag_id tags: id | name And i'm using this query to search images containing x tags SELECT images.* FROM images INNER JOIN nodes ON images.id = nodes.image_id WHERE tag_id IN (SELECT tags.id FROM tags WHERE tags.tag IN ("tag1","tag2")) GROUP BY ima...

nested join linq-to-sql queries

var result = ( from contact in db.Contacts where contact.ContactID == id join referContactID in db.ContactRefferedBies on contact.ContactID equals referContactID.ContactID join referContactName in db.Contacts on contact.ContactID equals referContactID.ContactID orderby cont...

C# LINQ: Join and Group

I have two tables TableA aId aValue TableB bId aId bValue I want to join these two tables via aId, and from there, group them by bValue var result = from a in db.TableA join b in db.TableB on a.aId equals b.aId group b by b.bValue into x select new {x}; My code doesn't recognize the join after the group. In other words, the grou...

Fetch posts with attachments in a certain category?

I need to retreive a list of posts that have (at least) one attachment that belongs to a category in WordPress. The relation between attachments and categories I made by myself using the WordPress default method. Here's the query that i'm running right now: SELECT post.* FROM `bma_posts` AS post WHERE EXISTS ( SELECT 1 ...

C# LINQ join With Just One Row

I'm trying to make a query that grabs a single row from an SQL database and updates it. TableA AId AValue TableB BId AId BValue Ok, so TableA and TableB are linked by AId. I want to select a row in TableB based on AValue using a join. The following query is what I have and only grabs a value from TableB based on AId, I just don't...

MySQL: Data query from multiple tables with views

I want to create a query result page for a simple search, and i don't know , should i use views in my db, would it be better if i would write a query into my code with the same syntax like i would create my view. What is the better solution for merging 7 tables, when i want to build a search module for my site witch has lots of users an...

Merging two arrays in PHP

Hi everyone, I am trying to create a new array from two current arrays. Tried array_merge, but it will not give me what I want. $array1 is a list of keys that I pass to a function. $array2 holds the results from that function, but doesn't contain any non-available resuls for keys. So, I want to make sure that all requested keys comes ou...

Cannot have a qualifier in the select list while performing a JOIN w/ USING keyword.

I am looking at a practice test that doesn't have explanations about the correct answers. The question I'm confused about basically asks why the following SQL statement can never work: SELECT oi.order_id, product_jd, order_date FROM order_items oi JOIN orders o USING(order_id); The answer it gave was: "The statement would not execute ...

Join one row to multiple rows in another table

I have a table to entities (lets call them people) and properties (one person can have an arbitrary number of properties). Ex: People Name Age -------- Jane 27 Joe 36 Jim 16 Properties Name Property ----------------- Jane Smart Jane Funny Jane Good-looking Joe Smart Joe Workaholic Jim Funny Jim Young I wo...

Data retrieval and Join operations with cluster db server

If any database spreads across multiple servers (ex. Microsoft Sql Server), how can we do join or filter operations. In my scenario, if suppose: A single table spreads across multiple servers how can we filter rows based on user input? If master table is there on one db server and transaction table is at another db server, how can we d...

NHibernate join table criteria and alias problem

Hi all. I am trying to query a table that looks like this CatalogProduct CatalogId - FK to Catalog ProductId - FK to Product The product table has a ParentProductId which is an FK to itself. using the NHibernate criteria API, i need to get a list of CatalogProducts where the CatalogId is and the ProductId is the Product.ParentPro...