outer-join

I am using Oracle SQL, so outer joins have the nice (+) syntax. I should warn you that I am not allowed to redesign the database; I work for a large organization. Here are some example tables: People PersonID Name 1 Elmo 2 Oscar 3 Chris Attribute PersonID Attribute 1 Happy 1 Muppet 1 Popular 2 Grouchy 2 Muppet 2 Popular 3 Programmer I want a list of people and I want to know whether we have knowledge of them being happy or grouchy. The following is the output I want: Name Mood Elmo Happy Oscar Grouchy Chris So here is the query I thought I would use: SELECT p.Name, a.Attribute FROM People p,

How can I outer merge two data frames in place in pandas? For example, assume we have these two data frames: import pandas as pd s1 = pd.DataFrame({ 'time':[1234567000,1234567005,1234567009], 'X1':[96.32,96.01,96.05] },columns=['time','X1']) # to keep columns order s2 = pd.DataFrame({ 'time':[1234567001,1234567005], 'X2':[23.88,23.96] },columns=['time','X2']) # to keep columns order They could be merged with pandas.DataFrame.merge ( s3 = pd.merge(s1,s2,how='outer') ) or with pandas.merge ( s3=s1.merge(s2,how='outer') ), but it isn't in place. Instead, I'd like the merged data frame to replace

Similar to this question: Inner-join in clojure Is there a function for outer joins (left, right and full) performed on collections of maps in any of the Clojure libraries? I guess it could be done by modifying the code of clojure.set/join but this seems as a common enough requirement, so it's worth to check if it already exists. Something like this: (def s1 #{{:a 1, :b 2, :c 3} {:a 2, :b 2}}) (def s2 #{{:a 2, :b 3, :c 5} {:a 3, :b 8}}) ;=> (full-join s1 s2 {:a :a}) ; ; #{{:a 1, :b 2, :c 3} ; {:a 2, :b 3, :c 5} ; {:a 3, :b 8}} And the appropriate functions for left and right outer join, i.e.

I have a Kafka topic where I expect messages with two different key types: old and new. i.e. "1-new" , "1-old" , "2-new" , "2-old" . Keys are unique, but some might be missing. Now using Kotlin and KafkaStreams API I can log those messages with have same key id from new and old. val windows = JoinWindows.of(Duration.of(2, MINUTES).toMillis()) val newStream = stream.filter({ key, _ -> isNew(key) }) .map({key, value -> KeyValue(key.replace(NEW_PREFIX, ""), value) }) val oldStream = stream.filter({ key, _ -> isOld(key) }) .map({key, value -> KeyValue(key.replace(OLD_PREFIX, ""), value) }) val

Can somebody tell me, why does Linq to Entities translate many to 1 relationships to left outer join instead of inner join ? Because there's referential constraint on DB itself that ensures there's a record in the right table, so inner join should be used instead (and it would work much faster) If relation was many to 0..1 left outer join would be correct. Question Is it possible to write LINQ in a way so it will translate to inner join rather than left outer join . It would speed query execution a lot... I haven't used eSQL before, but would it be wise to use it in this case? Would it solve

If i write a sql: select * from a,b where a.id=b.id(+) and b.val="test" and i want all records from a where corresponding record in b does not exist or it exists with val="test", is this the correct query? You're much better off using the ANSI syntax SELECT * FROM a LEFT OUTER JOIN b ON( a.id = b.id and b.val = 'test' ) You can do the same thing using Oracle's syntax as well but it gets a bit hinkey SELECT * FROM a, b WHERE a.id = b.id(+) AND b.val(+) = 'test' Note that in both cases, I'm ignoring the c table since you don't specify a join condition. And I'm assuming that you don't really want