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问题 pe.fdaddress has strange characters before the number. This is preventing my code from joining properly. Is there any way to remove these characters to run my code properly? The addresses results are null because of this. Thanks SELECT ca.fdorgunit AS Facility , pt.fdmedrecnum AS Account , ca.fddos AS DOS , pe.fddob AS DOB , pe.fdssn AS SSN , ad.fdaddr1 AS [Address] FROM OPENQUERY (VISION, 'SELECT * FROM ci.tbcase') AS ca LEFT JOIN OPENQUERY (VISION, 'SELECT * FROM de.tbpatient') AS pt ON pt

问题 I have two tables: person id name car name person_id Currently the query goes like: SELECT person.name car.name FROM person, car WHERE person.id = car.person_id Now this works fine if there is a car associated with a person. However if there isn't, then the person won't get returned. If a person has no car, I want to return a row with the text 'No Car' in column car.name . 回答1: select person.name, coalesce(car.name, 'no car') from person left outer join car on person.id = car.person_id 回答2:

问题 I am trying to maintain bluetooth connection when the screen is off. So I created an app that you can discover bluetooth devices around and choose from list. Then pass the chosen bluetooth device to backgroundService class which will handle the rest.But I am getting null pointer when I try to get device from intent. Any help will be appreciated. Here is my code segments @Override public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) { if(btAdapter.isDiscovering()){

问题 See important new discoveries 1 and 2 at end of this explanation. I am running Postgres 9.1.3 and am having a weird left join issue. I have a table named consistent.master with over 2 million rows. It has a column named citation_id , and that column has no nulls. I can verify that with this: SELECT COUNT(*) FROM consistent.master WHERE citation_id IS NULL That returns 0 . Here's where it gets weird: if I LEFT JOIN this table to a temporary table, I get an error that I am trying to insert a

问题 See important new discoveries 1 and 2 at end of this explanation. I am running Postgres 9.1.3 and am having a weird left join issue. I have a table named consistent.master with over 2 million rows. It has a column named citation_id , and that column has no nulls. I can verify that with this: SELECT COUNT(*) FROM consistent.master WHERE citation_id IS NULL That returns 0 . Here's where it gets weird: if I LEFT JOIN this table to a temporary table, I get an error that I am trying to insert a

问题 I have the following MovieTheaterTbl table: Name Location Date TicketRevenue SnackRevenue BeverageRevenue AMC Alpine St. 8/14 100 80 60 Atlas Main St. 8/19 300 150 100 Atlas Lincoln Rd. 8/19 50 50 40 I would like to insert this data into a table called SummaryTbl, which should display the sum of the Revenue columns, grouped by the movie theater name. If any of the other columns are not identical for rows with the same name (for example the location differs in the 2 Atlas entries), I would

问题 I am new to assembly language. To be clear, this is homework. The problem is given a char *list, how can I find which character is the end of the string? So I have xor ecx, ecx; //counter loop1: mov esi, list; mov eax, [esi + ecx]; cmp eax, 0x00; //check if the character is null je end; inc ecx; jmp loop1; end: however, the loop does not terminate when it reaches the end of the string. I wonder what I have done wrong. I have been finding solution in books and online, but they all look like

问题 Run time error on main method in MovieList.java. I'm not sure my program design is fundamentally very good, but I'd like to know why it crashes. Thanks in advance. package javaPractical.week3; import javax.swing.*; public class Movie { //private attributes private String title; private String movieURL; private String year; private String genre; private String actor; // constructor Movie(String t, String u, String y, String g, String a) { this.title = t; this.movieURL = u; this.year = y; this

问题 suppose I have a data object that is uploaded by the user: data <- reactive({ inFile <- input$file if (is.null(inFile)) return(NULL) data <- read.csv(inFile$datapath) return(data) }) And suppose I want to delete columns in the dataset. I want to set it to global assignment so that I can run the UI multiple times and have each effect saved in the object. dataset <- reactive({ file1 <- data() file1[,input$deletecols] <<- NULL return(file1) }} }) However, when I run this, I get the error:

问题 in SQL Server , how do I verify if a query has returned NULL and run blocks depending on it . e.g. in query 1 , I want to check if count(*) is not null and then check if it has >0 . Should I use if exists here ? if select count(*) from tbl1 not is NULL then if select count(*) from tbl1 where count(*)>0 then raiserror() end if end if In Oracle one can say IF INSERTING THEN or IF updating THEN or if deleting then run a certain block of code based on a column . how do we do it in SQL Server ?