join

问题 I have been working on the SQLzoo problems but having trouble with the last one in the JOIN tutorial question #13 - List every match with the goals scored by each team as shown. Link: http://sqlzoo.net/wiki/The_JOIN_operation In the sample code they gave, it uses a case. I modified it like this: SELECT game.mdate, game.team1, CASE WHEN goal.teamid=game.team1 THEN 1 ELSE 0 END score1, game.team2, CASE WHEN goal.teamid=game.team2 THEN 1 ELSE 0 END score2 FROM game, goal WHERE game.id=goal

问题 Hi Friends I have to join 4 tables in SQL Server and need to Show Specific Coulmns in Data Grid View First Table : emp_details Second Table : tbl_designation Third Table : tbl_empcontribution Forth table : tbl_empdeduction Columns need to show in Data Grid View is 1.From First Table i need to show emp_id, emp_name , emp_pf 2.from Second Table i need to show designation_name 3.from third Table i need to show pfacc1 and pfacc2 4.From Fourth Table i need to show pf_percent and pf_max Try to

问题 Hi Friends I have to join 4 tables in SQL Server and need to Show Specific Coulmns in Data Grid View First Table : emp_details Second Table : tbl_designation Third Table : tbl_empcontribution Forth table : tbl_empdeduction Columns need to show in Data Grid View is 1.From First Table i need to show emp_id, emp_name , emp_pf 2.from Second Table i need to show designation_name 3.from third Table i need to show pfacc1 and pfacc2 4.From Fourth Table i need to show pf_percent and pf_max Try to

问题 select * from order ------------------- |orderID|productID| ------------------- | 1 | 234 | | 2 | 234 | | 3 | 123 | ------------------- select * from product_supplier ------------------------------------------- |ID|supplierID|productID|cost_price|latest| ------------------------------------------- |1 | 1 | 234 | 1.00 | 0 | |2 | 1 | 234 | 0.50 | 1 | |3 | 2 | 123 | 0.75 | 1 | ------------------------------------------- desired result ------------------------------ |orderID|productID|cost_price|

问题 I have two dataframes and I would like to join them based on one column, with a caveat that this column is a timestamp, and that timestamp has to be within a certain offset (5 seconds) in order to join records. More specifically, a record in dates_df with date=1/3/2015:00:00:00 should be joined with events_df with time=1/3/2015:00:00:01 because both timestamps are within 5 seconds from each other. I'm trying to get this logic working with python spark, and it is extremely painful. How do

问题 I have installs table with installs that have the same user_id but different install_date . I want to get all revenue records joined with nearest install record by install_date that is less then revenue_date because I need it's source field value for next processing. That means that output rows count should be equal to revenue table records. How can it be achieved in BigQuery? Here is the data: installs install_date user_id source -------------------------------- 2020-01-10 user_a source_I

问题 I am having trouble with selecting all rows from a table and populating non matching ones with 0. Table "modul" ---------------------------------------------------------- | id | menu_name | modul_name | all_access | ---------------------------------------------------------- 1 books book 0 2 cds cd 0 3 tapes tape 0 table "user" -------------------- | id | username | -------------------- 1 vedran table "user_modul" ------------------------------------------ | id | user_id | modul_id | active |

问题 I am having trouble with selecting all rows from a table and populating non matching ones with 0. Table "modul" ---------------------------------------------------------- | id | menu_name | modul_name | all_access | ---------------------------------------------------------- 1 books book 0 2 cds cd 0 3 tapes tape 0 table "user" -------------------- | id | username | -------------------- 1 vedran table "user_modul" ------------------------------------------ | id | user_id | modul_id | active |

问题 I have a meetingRepository class that returns IEnumerable and an attendeeRepository class that returns IEnumerable<Attendee> public class meetingRepository { IEnumerable<Meeting> GetAll() { //return all Meetings } } public class attendeeRepository { IEnumerable<Attendee>GetAll() { //return all Attendees } } public class Meeting { public int Id { get; set; } public DateTime Date { get; set; } public string FilePath { get; set; } public int Duration { get; set; } public IEnumerable<Attendee>

问题 I would like to used nested full_join to merge several data frames together. In addition, I am hoping to be able to add suffixes to all of the columns so that when the data frames are merged each column name indicates which data frame it came from (e.g., a unique time identifier like T1, T2, ...). x <- data.frame(i = c("a","b","c"), j = 1:3, h = 1:3, stringsAsFactors=FALSE) y <- data.frame(i = c("b","c","d"), k = 4:6, h = 1:3, stringsAsFactors=FALSE) z <- data.frame(i = c("c","d","a"), l = 7