inner-join

问题 I have the following query var customers = from customer in context.tblAccounts join assoc in context.tblAccountAssociations on customer.AccountCode equals assoc.ChildCode where customer.AccountType == "S" || customer.AccountType == "P" select customer, assoc; C# does not like the "assoc" at the end. My error message is: A local variable named 'assoc' cannot be declared in this scope because it would give a different meaning to 'assoc', which is already used in a 'child' scope to denote

问题 I have two tables: contactperson and contactpersonlocale . Table contactperson : contactpersonID (Primary Key) tag (VARCHAR) Table contactpersonlocale : contactpersonlocaleID (Primary Key) contactpersonID (Foreign Key to contactperson table) function (VARCHAR) name (VARCHAR) locale (VARCHAR) In my Contactperson Entity I have: /** * @var integer * * @ORM\Column(name="contactpersonID", type="integer") * @ORM\Id * @ORM\GeneratedValue(strategy="IDENTITY") */ private $contactpersonid; /** * @ORM

问题 i have the following statement in a stored procedure that is returning strange results. Given two columns where one (RL) is less than 0 e.g -2, it should add 2 to another column (HD). If the negative value was -8 it should add 8 to the HD column. In a test ive just done, the RL column had 0 and HD was 2. I changed the RL to -2 and run the code. I was EXPECTING : RL = 0 and HD = 4. INSTEAD the RESULT was RL = 0 and HD = 5. I think the problem is due to the presence of the join. How would i

问题 I need your help with a inner join and max. I already researched other questions but I could not solve... I have three tables: member (member_id, name) location (location_id, name, order) member_location (id, member_id, location_id) I need select just the record from member_location with the highest order group by member_location.memberId. Example: Member 1, Jack Sparrow Location 1, Mexico, 2 2, Punta Cana, 3 3, Cuba, 1 member_location 1, 1, 3 1, 1, 2 1, 1, 1 On member_location I have 3

问题 Let's say I have the following SQL query: SELECT * FROM employee INNER JOIN department ON employee.EmpID = department.EmpID I wanted to ask, why I am getting two EmpID columns, and how can I get only one of those, preferably the first. I'm using SQL server 回答1: SELECT employee.EmpID, employee.name, ... FROM employee INNER JOIN department ON employee.EmpID=department.EmpID Be precise and specify which columns you need instead of using the astrisk to select all columns. 回答2: You get all columns

问题 first time asking a question on Stack Overflow... Amazing resource, but there's just one thing that's really baffling me as a newcomer to SQL. I have three tables and I would like to obtain the names of all the Mentors who are linked to Bob's students. Table 1: TEACHERS ================ ID Name ================ 1 Bob Table 2: STUDENTS =================================== STUDENT_ID Name TEACHER_ID =================================== 1 Jayne 1 2 Billy 5 3 Mark 2 Table 3: MENTOR_RELATIONSHIPS ==

问题 I have a table A and a table B. I am selecting information from table A where I need only the information from table A where tabel B joins table A. I have indexes on columns that are joint and on the WHERE clause. This is the select code: SELECT * FROM tableA INNER JOIN tableB AS tableB ON tableB.id = tableA.id AND tableB.type = 'car' When I use explain I can see that mysql is using a full table scan for all the rows in tableA. Further it properly uses the index to join tableB. So what Mysql

问题 This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. Closed 6 years ago . i have a select query with inner join i try it in phpmyadmin it work fine but when i try it in the browser it display this error msg : You have an error

问题 Hi friends I have 3 table topups, withdraws and transfers these 3 tables belongs to the user table. I have to find all the records which belongs to the users. I tried with inner join as follows:- SELECT * FROM users u INNER JOIN topups t ON u.id = t.user_id INNER JOIN withdraws w ON u.id = w.user_id INNER JOIN transfers tf ON u.id = tf.user_id But this query returns only the common records between the 3 tables. i have to find all those records which belongs to the user for each table. Suppose

问题 I currently have this query set-up: SELECT topic.content_id, topic.title, image.location FROM mps_contents AS topic INNER JOIN mps_contents AS image ON topic.content_id = image.page_id WHERE topic.page_id = (SELECT page_id FROM mps_pages WHERE page_short_name = 'foo' ) AND image.display_order = '1' This is because I want to merge two rows from the same table in one row. This is a simplified setup of the table ----------------------------------------------------------- | page_id | content_id |