multimap

RavenDB multi map

大兔子大兔子 提交于 2019-12-20 03:24:21
问题 I have a DB containing many tables, and every table has different properties, and I want to achive the following: Create and index on all of the properties (from every table). The problem is that I don't have a class for every table for I have used dynamic classes to insert them to the DB. So how can I create an index that given a string will return all documents that one of their properties contains that string? Another problem needed to be solved is that in future Tables insertion I can add

Is std::multimap Really Just Nested Vectors

落花浮王杯 提交于 2019-12-19 10:15:54
问题 I want to use a std::multimap container, but I need to know that it will always maintain order, as in the first element in will be the first element iterated over and the second will always be the second. What I'm asking is this: Is std::multimap< key, value > equivalent to std::vector< std::pair< const key, std::vector< value > > > 回答1: A multimap is not the equivalent of a vector, not in terms of implementation. Multimaps are usually implemented as a binary search tree. The elements of a

Is std::multimap Really Just Nested Vectors

雨燕双飞 提交于 2019-12-19 10:15:00
问题 I want to use a std::multimap container, but I need to know that it will always maintain order, as in the first element in will be the first element iterated over and the second will always be the second. What I'm asking is this: Is std::multimap< key, value > equivalent to std::vector< std::pair< const key, std::vector< value > > > 回答1: A multimap is not the equivalent of a vector, not in terms of implementation. Multimaps are usually implemented as a binary search tree. The elements of a

How can I create a Multimap in Java on Android

那年仲夏 提交于 2019-12-19 07:05:01
问题 Where can I find an implementation of multimap for Java that will work on Android without having to include any other classes etc. The implementations I've found all require other things which require other things and it gets messy quick. I'm porting a project from C++ and am new to java (and this project as well so I'm trying to keep things as identical as possible while getting it working) so any references or examples would be great. 回答1: You could use a Map and a List to create a multimap

Can I continue to use an iterator after an item has been deleted from std::multimap<>? [duplicate]

浪子不回头ぞ 提交于 2019-12-18 12:42:13
问题 This question already has answers here : What happens if you call erase() on a map element while iterating from begin to end? (3 answers) Closed 5 years ago . Can I continue to use an multimap iterator even after a call to multimap::erase()? For example: Blah::iterator iter; for ( iter = mm.begin(); iter != mm.end(); iter ++ ) { if ( iter->second == something ) { mm.erase( iter ); } } Should this be expected to run correctly, or is the iterator invalidated following the call to erase?

Why does it.next() throw java.util.ConcurrentModificationException?

我的梦境 提交于 2019-12-18 11:56:12
问题 final Multimap<Term, BooleanClause> terms = getTerms(bq); for (Term t : terms.keySet()) { Collection<BooleanClause> C = new HashSet(terms.get(t)); if (!C.isEmpty()) { for (Iterator<BooleanClause> it = C.iterator(); it.hasNext();) { BooleanClause c = it.next(); if(c.isSomething()) C.remove(c); } } } Not a SSCCE, but can you pick up the smell? 回答1: The Iterator for the HashSet class is a fail-fast iterator. From the documentation of the HashSet class: The iterators returned by this class's

compare two multimaps c++

房东的猫 提交于 2019-12-17 20:34:12
问题 I have two multimaps.i would like to create a new multimap which has the common key-value pairs in the given those two multimaps: for eg: #include <iostream> #include <string> #include <map> using namespace std; int main () { multimap<std::string, std::string> m; multimap<std::string, std::string> n; m.insert(multimap<string,string>::value_type("1-2","1-1")); m.insert(multimap<string,string>::value_type("1-2","1-2")); m.insert(multimap<string,string>::value_type("1-2","1-3")); m.insert

How to build a multimap from a list of tuples in Scala?

主宰稳场 提交于 2019-12-17 20:16:16
问题 Suppose I have a list of tuples List[(A, B)] . What is the best way to convert it to a multimap , which maps A to Set[B] ? Can I build an immutable multimap ? 回答1: Can I build an immutable multimap ? Not with the MultiMap in Scala standard library. Of course, you can write your own. What is the best way to convert it to a multimap? import scala.collection.mutable.{HashMap, Set, MultiMap} def list2multimap[A, B](list: List[(A, B)]) = list.foldLeft(new HashMap[A, Set[B]] with MultiMap[A, B]){

Using boost::iostreams::mapped_file_source with std::multimap

a 夏天 提交于 2019-12-17 14:23:18
问题 I have a rather large amount of data to analyse - each file is about 5gigs. Each file is of the following format: xxxxx yyyyy Both key and value can repeat, but the keys are sorted in increasing order. I'm trying to use a memory mapped file for this purpose and then find the required keys and work with them. This is what I've written: if (data_file != "") { clock_start = clock(); data_file_mapped.open(data_file); data_multimap = (std::multimap<double, unsigned int> *)data_file_mapped.data();

How to build this Java Collection from a ResultSet

早过忘川 提交于 2019-12-14 03:11:02
问题 I have data from a ResultSet that contains three fields: DataType, Data, DataValue. I want to build a Java Collection, and next build the JSON encode. This is the output when I try to print: System.out.println(resultSet.getString("DATATYPE") + " --> " + resultSet.getString("DATA") + " --> " + resultSet.getString("DATAVALUE")); Output: Address --> Test --> JHGJHGJKG Address --> City--> Some city Address --> State --> Some state Address --> Downtown --> Some downtown Address --> Telephone -->