I have been struggling to return the count of courses from this XML file that contain "Cross-listed" as their description. The problem I encounter is because I am using for, it iterates and gives me "1 1" instead of "2". When I try using let instead I get 13 which means it counts all without condition even when I point return count($c["Cross-listed"]. What am I doing wrong and how can I fix it? Thanks in advance
for $c in doc("courses.xml")//Department/Course
where some $desc in $c/Description
satisfies contains($desc, "Cross-listed")
return count($c)
The problem I encounter is because I am using for
You are quite correct. You don't need to process items individually in order to count them.
You've made things much too difficult. You want
count(doc("courses.xml")//Department/Course[Description[contains(., "Cross-listed"]])
The key thing here is: you want a count, so call the count() function, and give it an argument which selects the set of things you want to include in the count.
Related
I've noticed a slight problem with how my API is working where I'm using Spring Data JPA.
My query looks something along the lines of:
#Query("SELECT p.id AS id, COUNT(l) AS likes FROM Post p LEFT JOIN Like l ON l.post = p WHERE p.location.id = ?1")
My actual query is bigger, this this contains everything necessary to explain what the issue is. This query will return a list, but assume the location does not exist, it should return null or an empty list, correct? Oh, how wrong you are, my sweet summer child!
This query will instead always return a list of at least one element, regardless of whether or not there are any posts linked to said location.
[{"id": null, "likes": 0}]
That is what the result looks like when serialized to JSON. I am not quite sure what to do about this little predicament, as I obviously don't want to return a list with faulty data, but needing to use processing to filter out duds also seems dumb and unnecessary.
Is there any way to prevent this that I've yet to find? If it is of any relevance, I am using projections currently for my responses.
What I've tried so far:
Adding a not null condition for fields. Does not work, ignored by COUNT.
Adding constraints to all fields #NotNull. Does not work, will still become null.
For what it's worth, I've tried different kinds of joins, though anything but LEFT JOIN doesn't make much sense.
I haven't been able to find any other case which resembles this either, although it most likely exists, but is drowned out by everything else. I'm not quite sure what can be done in this regard, so I'm curious if it's just a quirk with the framework, or if there is an actual solution.
It might be possible to solve through native queries, but I would prefer not to use them.
I'm no SQL expert but I believe that a left join will give you this result if the ID does not exist.
Have you run the query in your DB? Doesn't it give you one row in your result set for IDs that do not exist?
I believe this is intended to say there is a 0 match.
You might want to validate your query before running it. Meaning checking that the location exists first.
As the issue is inherently due to a COUNT and CASE keyword in my real query, resulting in there always being at least one row, and I can't find any method of doing this automatically, the solution I've used is the following:
List<Item> items = repository.customQuery(id);
if (0 < items.size() && null == items.get(0).getId()) {
items.remove(0);
}
The first condition is arbitrary as I know there is always at least one entry, but is done just as a safety measure. A try-catch block would do the trick as well. In the case where you use a primitive int instead of Integer, you'd need to initialize the value in the constructor to something which would normally never be present in the database, such as -1.
If anyone knows of a better method, I'd love to know about it.
I'm trying to find a way to see if I can find a way to determine if a time that I stipulate falls between two other times. For example:
Start End
11:33:48 11:53:48
12:20:22 12:38:21
12:39:27 13:00:09
14:16:23 14:20:49
14:20:54 14:22:56
Then, I want to check if a cell (here the value of 12:50 in cell E30) falls between ANY two values in a range in THE SAME ROW. For me, I can get the obvious way to check for this in one row, and this simple version totally works:
=If(AND(E30>A4,E30<B4), "TRUE", "FALSE")
However, I want to check if that number falls within ANY of the values within the ROWS above cells in a range, and I can't get that to work. For example, I tried this and it didn't work:
=If(AND(E30>A:A,E30<B:B), "TRUE", "FALSE")
I also tried a simple countif variation but that didn't do it either:
=COUNTIFS(A:A,">"&E30,B:B,"<"&E30)
Any advice on how to adjust one of these formulas to get it to work?
Try switching the angle brackets around:
=COUNTIFS(A:A,"<"&E30,B:B,">"&E30)
I think this should work for the above data set -
=IF((FILTER(A2:B6, D2>A2:A6,D2<B2:B6)),TRUE,FALSE)
This will give you if there is any match or not.
For the number of rows count that match -
=ROWS((FILTER(A2:B6, D2>A2:A6,D2<B2:B6)))
Alomsot =IF(Q2>R2,IF(AND($X$16>HOUR(Q2),$X$16<(HOUR(R2)+12)),1,0),IF(AND(HOUR($X$14)>=HOUR(Q2),HOUR($X$14)<=HOUR(R2)),1,0))
I've done dozens times, but now don't get what I'm doing wrong. I want to extract specific records, into 2 separate columns (I know that order wil not match), so I use:
//a/#href[contains(.; "github")]
and
//*[contains(text(); "Pricing:")]
But non of them is working - where my mistake?
(my sandbox: https://docs.google.com/spreadsheets/d/11Z3xybq_eYQvjn2-UBOomgeJxFrrsFoXKzF9yZSeASM/edit#gid=1841586203 with LT localle)
damn, those google sheet localles!!!... must be:
//a/#href[contains(., "github")]
and
//*[contains(text(), "Pricing:")]
I'll keep for further reference.
every time i want to get the Value of my DomAttr i get an TypeError:
My Code:
Wanted = page.getByXPath("//span[contains(.,'Some')]/parent::a/#href");
return this
[DomAttr[name=href value=URLSTRING]]
Now i want to geht the value (=URLSTRING) with Wanted.getNodeName();
but every Time i get the Error
Cannot find function getNodeValue in object [DomAttr[name=href value=
same when i use getValue
please help me
There are some things that make no sense in the code (particularly, because it is not complete). However, I think I can guess what the issue is.
getByXPath is actually returning a List (funny thing you missed the part of the code in which you specify it as a list and replaced it with a Wanted).
Note you should probably also have type warnings in the code too.
Now, you can see that the returned value is in square brackets. That means it is a List (confirming first assumption).
Finally, although you happened to miss that part of the code too, I guess you are directly applying the getValue to the list instead of the DomAttr elements in the list.
How to solve it: If you need more than 1 result iterate over the elements of the list (that Wanted word over there). If you need 1 result then user the getFirstByXPath method.
Were my guesses right?
I use libxmljs to parse some html.
I have a xpath query which has an "or" conjunction to retrieve basically the information of two queries
Example
doc.find("//div[contains(#class,'important') or contains(#class,'overdue')]")
this returns all the divs with either important or overdue...
Can I prefix or see within my result set which comes from which condition?
The result could be an array with an index for the match 0 for the first condition and 1 for the 2... Is this possible...
Or how can I find out which result comes from which query condition...
Thanks for any help...
P.S.: this is a simplified exampled of a sequence of elements which either have an important or an overdue item ... both, one or none of them... So I cannot go by looking for every second entry ... etc
This is the result I want to get...
message:{},
message:{
.....
important: "some immportant text",
overdue: "overdue date,
.....
}
There is no way to know which clause of an or XPath query caused a particular result to be included. It's simply not information that's kept around.
You'll either need to do entirely separate queries for important and overdue, or do one large query to get the entire result set (as you are now) and then further test each result's class to find out which one it is.