key-value

how to extract multi level dictionary keys/values in python

由 南楼画角 提交于 2020-01-17 13:13:36
问题 There is a two level dictionary in python: for instance here: index[term][id] = n how to get the term and n when id = 3 ? Or it would be perfect if it returns in a form like result[id] = [term, n] 回答1: Iterate over the nested dict and create new dict to map the values in the desired format. You can create your custom function like: def get_tuple_from_value(my_dict): new_dict = {} for term, nested_dict in my_dict.items(): for id, n in nested_dict.items(): new_dict[id] = [term, n] return new

JAXB Marshal and Unmarshal Map to/from <key>value</key>

由 心已入冬 提交于 2020-01-16 05:06:09
问题 I'm trying to marshal and unmarshal Map to/from value pairs. I can marshal the object successfully, however, I cannot unmarshal it from the xml. The unmarshal result is the key exist in the Map, however, its value is null. Here's the model I want to marshal and unmarshal: import java.util.Map; import javax.xml.bind.annotation.XmlAccessType; import javax.xml.bind.annotation.XmlAccessorType; import javax.xml.bind.annotation.XmlElement; import javax.xml.bind.annotation.XmlRootElement; import

Adding a single character to add keys in Counter

由 假装没事ソ 提交于 2020-01-15 07:40:29
问题 If the type of a Counter object's keys is str , i.e.: I could do this: >>> vocab_counter = Counter("the lazy fox jumps over the brown dog".split()) >>> vocab_counter = Counter({k+u"\uE000":v for k,v in vocab_counter.items()}) >>> vocab_counter Counter({'brown\ue000': 1, 'dog\ue000': 1, 'fox\ue000': 1, 'jumps\ue000': 1, 'lazy\ue000': 1, 'over\ue000': 1, 'the\ue000': 2}) What would be a quick and/or pythonic way to add a character to all keys? Is the above method the only way to achieve the

How to store a key and value in a table from a JSON object in MySQL

由 那年仲夏 提交于 2020-01-15 03:42:06
问题 I'm having a MySQL database tables namely ds_message and ds_params, it table ds_message contains a JSON object in each row. I would like to store the key and value of a JSON object into the table ds_params for all the records by referring the ds_message primary key id Table: ds_message _____________________________________________________________________________________ id key_value _____________________________________________________________________________________ 1 '{"a":"John", "b":"bat"

Max key/value length in 'application configuration' files

由 ♀尐吖头ヾ 提交于 2020-01-14 13:48:30
问题 What's the maximum allowed length for MyKey and MyValue in a configuration file? <configuration> <appSettings> <add key="MyKey" value="MyValue" /> </appSettings> </configuration> 回答1: As per knowledge there is no limitation the key value pair in webconfig file ..... if you are planning to add object to config file check this post will help you to achieve your task How to store custom objects in web.config ? 来源： https://stackoverflow.com/questions/6382758/max-key-value-length-in-application

ANSI C hash table implementation with data in one memory block

由 放肆的年华 提交于 2020-01-12 10:13:55
问题 I am looking for an open source C implementation of a hash table that keeps all the data in one memory block, so it can be easily send over a network let say. I can only find ones that allocate small pieces of memory for every key-value pair added to it. Thank you very much in advance for all the inputs. EDIT: It doesn't necessarily need to be a hash table, whatever key-value pair table would probably do. 回答1: On a unix system I'd probably utilise a shared memory buffer (see shm_open()), or

ANSI C hash table implementation with data in one memory block

由 谁说我不能喝 提交于 2020-01-12 10:13:07
问题 I am looking for an open source C implementation of a hash table that keeps all the data in one memory block, so it can be easily send over a network let say. I can only find ones that allocate small pieces of memory for every key-value pair added to it. Thank you very much in advance for all the inputs. EDIT: It doesn't necessarily need to be a hash table, whatever key-value pair table would probably do. 回答1: On a unix system I'd probably utilise a shared memory buffer (see shm_open()), or

选择合适Redis数据结构，减少80%的内存占用

由 二次信任 提交于 2020-01-11 06:50:42
前言 redis作为目前最流行的nosql缓存数据库，凭借其优异的性能、丰富的数据结构已成为大部分场景下首选的缓存工具。 由于redis是一个 纯内存 的数据库，在存放 大量数据 时，内存的占用将会非常可观。那么在一些场景下，通过选用 合适数据结构 来存储，可以 大幅 减少内存的占用，甚至于可以减少80%-99%的内存占用。 利用zipList来替代大量的Key-Value 先来看一下场景，在Dsp广告系统、海量用户系统经常会碰到这样的需求，要求根据用户的某个 唯一标识 迅速 查 到该 用户id 。譬如根据mac地址或uuid或手机号的md5，去查询到该用户的id。 特点是数据量很大、千万或亿级别，key是比较长的字符串，如32位的md5或者uuid这种。 如果不加以处理，直接以key-value形式进行存储，我们可以简单测试一下，往redis里插入1千万条数据，1550000000 - 1559999999，形式就是key（md5（1550000000））→ value(1550000000)这种。 然后在Redis内用命令 info memory 看一下内存占用。 可以看到，这1千万条数据，占用了redis共计1.17G的内存。当数据量变成1个亿时，实测大约占用8个G。 同样的一批数据，我们换一种存储方式，先来看结果： 在我们利用zipList后，内存占用为123M

Can't add keyValuePair directly to Dictionary

由 强颜欢笑 提交于 2020-01-10 03:27:08
问题 I wanted to add a KeyValuePair<T,U> to a Dictionary<T, U> and I couldn't. I have to pass the key and the value separately, which must mean the Add method has to create a new KeyValuePair object to insert, which can't be very efficient. I can't believe there isn't an Add(KeyValuePair<T, U>) overload on the Add method. Can anyone suggest a possible reason for this apparent oversight? 回答1: Backup a minute...before going down the road of the oversight, you should establish whether creating a new

PHP: php and .html file separation

由 霸气de小男生 提交于 2020-01-07 08:07:37
问题 I'm currently working on separating HTML & PHP code here's my code which is currently working for me. code.php <?php $data['#text#'] = 'A'; $html = file_get_contents('test.html'); echo $html = str_replace(array_keys($data),array_values($data),$html); ?> test.html <html> <head> <title>TEST HTML</title> </head> <body> <h1>#text#</h1> </body> </html> OUTPUT: A it search and change the #text# value to array_value A it works for me. Now i'm working on a code to search "id" tags on html file. If it
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