left-join

问题 I know there is a lot of good questions answered on Left Joins , but I am having trouble finding something pertaining to my particular problem. I apologize for a possible repeated topic, but help would be greatly appreciated. I have two tables that contain gift card sales. I have to verify that the amounts match. I'm looking for help writing a query that will return everything from TABLE A even if there is no matching record in TABLE B. TABLE A | id | business_date | am_pm | gift_cards_sold |

问题 I have two tables table 1 name : depot_tracking ------------------------------------------------- depot_tracking_id | cont_details_id | date | ------------------------------------------------- 1 | 4 | 05-02-2015 | 2 | 1 | 25-03-2015 | 3 | 3 | 05-04-2015 | 4 | 2 | 15-02-2015 | 5 | 3 | 05-05-2015 | 6 | 2 | 23-03-2015 | 7 | 1 | 15-05-2015 | -------------------------------------------------- second table name : cont_details ----------------------------------- cont_no | cont_details_id | ---------

问题 I have the following HQL query: return entityManager().createQuery( "SELECT page FROM ProjectPage page" + " left join fetch page.categorySet as category " + " where page.id = :id " + " and category.parentCategory is null " + " and (category.status != :status_val) " ,ProjectPage.class).setParameter("id", id) .setParameter("status_val", 1).getSingleResult(); the problem is that the conditions in the where clause fails, for example, the query returns category objects whose status is 1 and

问题 I have the following HQL query: return entityManager().createQuery( "SELECT page FROM ProjectPage page" + " left join fetch page.categorySet as category " + " where page.id = :id " + " and category.parentCategory is null " + " and (category.status != :status_val) " ,ProjectPage.class).setParameter("id", id) .setParameter("status_val", 1).getSingleResult(); the problem is that the conditions in the where clause fails, for example, the query returns category objects whose status is 1 and

问题 I am trying to change my sub-query in to a join where it selects only one record in the sub-query. It seems to run the sub-query for each found record, taking over a minute to execute: select afield1, afield2, ( select top 1 b.field1 from anothertable as b where b.aForeignKey = a.id order by field1 ) as bfield1 from sometable as a If I try to only select related records, it doesn't know how to bind a.id in the nested select. select afield1, afield2, bfield1 from sometable a left join ( select

问题 I am trying to change my sub-query in to a join where it selects only one record in the sub-query. It seems to run the sub-query for each found record, taking over a minute to execute: select afield1, afield2, ( select top 1 b.field1 from anothertable as b where b.aForeignKey = a.id order by field1 ) as bfield1 from sometable as a If I try to only select related records, it doesn't know how to bind a.id in the nested select. select afield1, afield2, bfield1 from sometable a left join ( select

问题 SELECT * from meets LEFT JOIN teams as hteam on meets.meet_hometeam=hteam.team_id LEFT JOIN teams as ateam on meets.meet_awayteam=ateam.team_id LEFT JOIN teams as altloc on (meets.meet_altloc=altloc.team_id and meets.meet_altloc!='') where meet_date between ($now+(4*86400)) and ($now+(5*86400) or meets.meet_id='2') $var = $queryvar->fetch_object(); Thanks what I'm having issues with is when I call $var->ateam.team_town it is just treating the dot as a concatenation and not as an object to the

问题 I'm building a nested comments feature. I have submissions_comments which looks like: +---------------+------------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +---------------+------------------+------+-----+---------+----------------+ | id | int(10) unsigned | NO | PRI | NULL | auto_increment | | user_id | int(10) unsigned | NO | MUL | NULL | | | submission_id | int(11) | NO | MUL | NULL | | | comment | text | NO | | NULL | | | parent_id |

问题 I have 2 tables: town which stores 290 towns hospital which stores hospitals referenced in 67 different towns The following query returns 290 rows which is what the LEFT JOIN is supposed to do: SELECT a.code, count(b.*) FROM town a LEFT JOIN hospital b ON a.code = b.town_code GROUP BY a.code ; Now, the following query in which I just add a WHERE clause to select a type of hospital returns 56 rows: SELECT a.code, count(b.*) FROM town a LEFT JOIN hospital b ON a.code = b.town_code WHERE b.type

问题 I have 2 datatables of identical structure, and I need to find all records that appear on the first, but not on the second. What makes it more complicated is that the matching needs to be on 3 columns instead of one. Background - I'm writing a replication process where rows of data arrive in an XML transaction and they need to be matched against the 'host' database to find out if there are any items that need to be added. The basic algorithm is as follows: Load in transaction dataset