563 questions
0
votes
0
answers
33
views
How does a Bigtable client know which tablet server to query to read/write data?
From the Bigtable paper I've read, I understand that Bigtable data is split into multiple tablets.
It follows a 3 tier hierarchy.
The file location of the first tablet/Root tablet is obtained by ...
- 141
0
votes
1
answer
341
views
Why is the order page on my WooCommerce store so slow?
Since WooCommerce 8.9 came out, I've noticed a big slowdown when I click on an order page from WooCommerce -> Orders in my dashboard. I have a big store with many orders, and it takes many seconds ...
- 108k
2
votes
1
answer
134
views
Substract values dictionary from another dictionary's values
I have a coffee machine that gives a user 3 options to choose from: espresso, latte, cappuccino. The ingredients and cost of the chosen item are stored in a dictionary in the variable MENU. After the ...
- 21
0
votes
3
answers
362
views
Mocking useStorage() using @nuxt/test-utils
The goal is to write a test for a function that uses KV storage, under the hood provided by Nitro, in the Nuxt app. On the client side useStorage() is automatically imported. When writing a test, ...
- 418
0
votes
2
answers
318
views
Comparison of .NET Key value pair Collections
I write in C# and am faced with the requirement of storing/retrieving a large number of string Key Value pairs from disk. To minimize the total amount of Ram consumed by the application, I would read ...
- 351
1
vote
1
answer
39
views
JSON From HTTP Print Value With Python
I'm grabbing JSON from an http link. I can print the entire json string, and I can print all of the key values. What I'm trying to do is to get only certain values based on an ID.
Json output:
{
&...
0
votes
2
answers
549
views
How to list all entries in Deno KV?
I don't see an example on Operations | Deno Docs. I don't know where I've missed.
- 2,874
0
votes
0
answers
29
views
How does bulkload in databases such as hbase/cassandra/KV store work?
I understand from https://svn.apache.org/repos/asf/hbase/hbase.apache.org/trunk/0.94/book/arch.bulk.load.html that we can process data into HBase data files and ask hbase to bulk load the data files ...
- 935
0
votes
0
answers
20
views
Getting values of my_dict and assign them to a variable called my_values
Please can someone help out. I tried to assign values I got from my_dict to store in a new variable my_values and it is giving me error. See below what I tried to do:
my_dict = {"key_1": 1, &...
- 1
2
votes
0
answers
238
views
DynamoDB table model code supporting design with more than one sort keys
I'm working with a DynamoDB table where each partition key is associated with multiple sort keys. I need to fetch all items in one partition key. I understood that I would need to get List of these ...
- 150
0
votes
1
answer
185
views
custom `prefix_extractor` per `ColumnFamilyOptions` in RocksDB
I am looking for a way to have a fixed size prefix for one specific column family in a RocksDB database, as this column family will be used to implement a join index between two existing "full ...
- 26.9k
0
votes
0
answers
66
views
iCloud Key-Value storage does not work for users with full iCloud
I have a flutter app I developed and some of the users cannot use our backup system which uses iCloud Key-Value storage. These users all have one thing in common. Full iCloud. If they turn off the app ...
- 47
-2
votes
4
answers
445
views
Is there a way to keep track of an object-property's value-history, like memorizing and recalling any of its recent values?
Say I have a method that changes a value based on what the current value is. I will just make it very simple here:
changeValue(){
if(!this.value){
this.value = 'value1'
}
else if(...
- 25
1
vote
0
answers
50
views
Balancing LSM key-value storage access between users, and 'hanging' problem
Typical LSM key-value databases like goleveldb are unpredictable in throughput. They can write a big batch of data into L0 but then get 'stuck' until all so called 'compactions' are finished. In my ...
- 395
0
votes
0
answers
70
views
What is the best open source software to store and access data from 1MB to 10GB size key-value-based?
I'm searching for an open source software to store data from 1MB to 10GB key-value-based? In average an entry will have a size of 500MB.
It should run in a Docker container with a mounted volume as ...
- 1
1
vote
0
answers
130
views
Select blob keys by prefix in Cassandra
I am using a Cassandra-compatible database (that is ScyllaDB) I use it purely as a Key-Value Store with keys and values being Blob, that is Vec<u8> type. That is, it is created by
CREATE ...
0
votes
2
answers
424
views
Do memtables ever actually use trees over skip lists?
I keep seeing articles that mention how memtables are usually backed by a self balancing tree like AVL tree or red-black tree.
Examples:
https://www.linkedin.com/pulse/data-structures-powering-our-...
- 43
2
votes
4
answers
522
views
How to append the list in a dictionary into its own column?
I have a dictionary with lists as values as you can see here:
my_dict = {1: ['Home', 'Stories'], 2: ['Sounds', 'Stories', 'Home', 'Home', 'Stories'], 3: ['Journeys / Series', 'Journeys / Series', '...
1
vote
0
answers
52
views
Statically allocated, optimizable, sparse key-value store in C?
Let's say, I want to use 16-bit unsigned integers to describe some category (say, as in the example below, fruits); and:
I want to specify a total of all these categories first, - and then choose a ...
- 5,364
0
votes
1
answer
66
views
Which is the correct way to define globals values for labels in React?
im trying to search how to define a dictionary of labels values for use in all the pages of my React app, i dont know which is the correct way or the best practice for that.
Im thinking something like ...
- 415
-1
votes
1
answer
359
views
Internal working of DynamoDB while Querying [closed]
How does read query works in dynamoDB? I know that it internally calculates the hash based on the partition key and finds out the in which partition the item is present. After finding the partition ...
0
votes
1
answer
782
views
For loop not saving to dataframe
First question here, I hope it makes sense how I write this out.
I am searching a massive lists of emails, and if they are found in google (I am in germany, thus the german in the strings) updating ...
- 3
0
votes
1
answer
716
views
How are keys locked in KV Stores?
I am building a distributed KV store just to learn a little bit more about distributed systems and concurrency. The implementation of the KV store I am building is completely transactional, with an in-...
1
vote
1
answer
382
views
How to delete entries in DynamoDb having a specified prefix
In BatchWriteItem we can do only DeleteRequest and PutRequest and DeleteRequest is only about a single key. However, we may want to delete all keys having a specified prefix.
The expensive solution to ...
0
votes
3
answers
1k
views
How can I store and retrieve form values as data in local storage, and then display them in the UI?
I want to store the input values from a user, that is its name, age and gender to local storage and then display it to UI.
What happens right now is that after displaying a newly registered student at ...
-1
votes
1
answer
99
views
Put multiple values with same key in one row
I have such result:
{'name': name1 , 'pic': pic1}
{'name': name1 , 'pic': pic2}
{'name': name1 , 'pic': pic3}
{'name': name2 , 'pic': pic4}
{'name': name2 , 'pic': pic5}
{'name': name2 , 'pic': pic6}
{...
- 1
0
votes
2
answers
494
views
At each form submit how does one put a new data item into local storage?
I want that every time a form is submitted, a new equipment with the equipment number as KEY is created in the local storage.
E.g.
LocalStorage:
Key:
Value:
E123456789
ordernumber: 456, date: 05.11....
- 31
0
votes
1
answer
53
views
Xamarin.iOS/How to retrieve a record from CloudKit by using only the Key
I was reading the Xamarin iOS documentation about CloudKit but it seems is not clear enough how to get the values of a specific record.
In the code below is what the documentation says how to fetch a ...
- 727
0
votes
1
answer
36
views
How to total up values from dictionary when creating a new list
Stock = {
'apple': .40,
'cheese': .90,
'banana': .60,
'pear': .60,
'steak': 3.00,
'salad': 1.00,
'ketchup': 1.00,
'wine': 5.00,
'beer': 4.50,
}
shoplist = []
for ...
- 55
4
votes
3
answers
3k
views
Is DynamoDB a wide-column store?
Sources indicate that DynamoDB is a key/value store, document store, and/or wide-column store:
At the core, DynamoDB is a key/value store.
If the value stored is a document, DynamoDB provides some ...
- 9,093
0
votes
2
answers
26
views
I want to get a key as input and a comparison of key value in if condition
It shows KeyError: ('Black in Black', 8.5)
album_rating={"Black in Black":8.5,"Believer":6,"SmackTac":7,"You":9}
a=(input("Enter the name:"))
For a ...
- 3
4
votes
1
answer
2k
views
RocksDB: range query on numbers
Is it possible to use RocksDB efficiently for range queries on numbers?
For example if I have billions of tuples (price, product_id) can I use RocksDB to retrieve all products that have 10 <= price ...
- 35.3k
1
vote
0
answers
54
views
KeyStore service with hard limits
I'm putting together a datastore technology that relies on a backing key-value store, and has Typescript generator code to populate an index made of tiny JSON objects.
With AWS S3 in mind as an ...
- 3,279
0
votes
1
answer
215
views
Convert list of values to a key value json
I'm trying to convert a list comma separated IP values (192.168.1.1,192.168.1.2,192.168.1.3, xxxx,xxxx) to a key value json so that at the end of all I can have a file with the structure below.
{
...
0
votes
2
answers
2k
views
Is there a way to extract the Key and Field values from a dictionary into separate variables?
I have a dictionary with items that look like this:
{'33515783': [('ID', '33515783'),
('Location', 'madeuptown'),
('Address1', ' 1221 madeup street')],..etc
Is there a way to have the Key values (...
- 129
2
votes
1
answer
255
views
How to define a simple KVStore effect 'mtl-style'?
I have experimented a little with the polysemy library and enjoyed working with the KVStore k v, which is simple abstraction of a Key-Value-Store. Now I was wondering how I would define a similar ...
- 853
0
votes
1
answer
2k
views
How to create a key value pair from two values [duplicate]
I'm returning key-value fields from the database, how do merge the two values into a new key-value pair?
{
"conditions": [{
"key": "target_condition",
&...
- 21
0
votes
1
answer
39
views
How do I assign a value to a word?
I'm creating a calculating list for the user to select from such as: pepsi, sprite, coke
and after user selects their fav drink, it will calculate: the calories(they all have diff. calories) + plus ...
- 1
0
votes
2
answers
723
views
leveldb why do we need sequence number
the sequence number does give a versioning information, but why do we need that? The SST structure itself already tells you which one is newer and which one is older: when we do compaction, record ...
- 3,141
1
vote
1
answer
442
views
Why MapDB is slower than LMDB and RocksDB?
I am testing the read performance of MapDB, LMDB and RocksDB. I am inserting 762207 data into these databases and trying to read a value from the databases using JMH(Java Micro Harashment). These are ...
- 13
0
votes
1
answer
535
views
How MapDB is different from other Key-Value store like RocksDb and LMDB?
I am testing the benchmark results of LMDB,RocksDB and MapDB. MapDB has an implementation to access the store (HTree and BTree) but other database doesn't provide any. Does this provide any ...
- 13
1
vote
1
answer
629
views
Eviction of data from Kafka key value state store
I am performing aggregation using kafkaStreams which actually keeps all my aggregated records into a keyValue state store against a specific key which i am generating to uniquely identify that ...
- 11
0
votes
1
answer
968
views
Using hashmaps and matching values
I re-made my code a bit to make it more clear of my scope. Hope it's more understandable now! I also added in-code instructions to make it more understandable! Essentially I want to match the 2 ...
- 434
1
vote
1
answer
90
views
How do I read and write to the google cloud datastore?
The documentation in google cloud's datastore section is very confusing to me.
I was under the belief datastore may be used as a key-value storage. (Similar to mongoDB) But I guess I misunderstood how ...
- 33
0
votes
3
answers
65
views
Python Dictionaries where the keys are from a list
How can I print the certain values of a dictionary,where I should iterate it’s keys from a list?
F.e. -> I have a list with codons: [‘AUU’,’GGG’], and let’s assume that auu and ggg is defined in a ...
0
votes
2
answers
48
views
How can I create a dictionary from an unordered list, where the list contains the keys which are then followed by multiple values?
I have multiple list which are ordered like the following list:
['SNOMEDCT:', '263681008,', '771269000', 'UMLS:', 'C0443147,', 'C1867440', 'HPO:', 'HP0000006', 'HPO:', 'HP0000006', 'UMLS:', 'C0443147']...
- 11
0
votes
1
answer
321
views
How key-value data storage (e.g Redis) store and query data
I'm curious about how key-value data storage store their data and query on it.
Normally, when give it a key to query, it will need to loop through the data and find the matched key then get its data ...
- 1,183
6
votes
1
answer
2k
views
Performance issue in Golang's key-value store (Badger DB)
In badgerDB, we have billions of keys of type string and values of type HashValueList. In our use case length of HashValueList might be in millions. We have to encode key and value in []byte before ...
- 420
0
votes
1
answer
187
views
Design data structure for storing data in key-value databases for blog website
I need to create a blogging website from end to end by using a key-value database as a primary database. But when I create the data structure for the project to store and query data based on project ...
0
votes
1
answer
153
views
What is the relation between a nodeId and a key in distributed hash tables?
My understanding of a distributed hash table is that every node can be identified uniquely by a nodeId and can store information, like host, port and values. Every node stores other nodeIds in (a) ...
- 207