Questions tagged [unique-data]

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Is using multiple UUIDs decrease chance of collisions exponentially?

For example if you have a single UUID with a collision probability of x, if you concatenate 2 UUIDs, does the collision probability become x^2? val0 = generate_uuid() val1 = generate_uuid() final_val ...
Joan Venge's user avatar
  • 1,960
0 votes
2 answers
539 views

Ensure unicity of a 10 characters alphanumeric String

I have a requirement of developing a service that must generate each day few millions of random and unique alphanumeric String of length 10 (I can't increase this length, this is a customer ...
Rouliboy's user avatar
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2 votes
4 answers
1k views

Algorithm for permutations of a string of characters, with no duplicate orders

I've seen a lot of good questions about similar problems but not exactly what I'm looking for. Given: a non-unique set of symbols (or characters) (1, 1, 2, 3) Expected: an output similar to this (...
triplethreat78's user avatar
-1 votes
1 answer
704 views

How to maintain unique, customer facing Booking or Reservation Ids

I am facing trouble in creating a unique, customer facing Booking Id. It's a simple thing to do at backend where we can create a UUID and maintain uniqueness. But the UUID looks ugly from a Frontend ...
blogbydev's user avatar
  • 161
1 vote
3 answers
1k views

Deduplicating data during batch processing

I constantly struggling to solve data duplication problems efficiently (storing data from any source to RDBMSes). My main concern is speeding up inserts/batch processing. Scenario: I read data from ...
appl3r's user avatar
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3 votes
2 answers
2k views

Should email be unique across application users?

I am working on a medical application which will be implemented for USA patients and health providers. I want that there should be only 1 record of a user without any duplication. And I believe that ...
naXa stands with Ukraine's user avatar
0 votes
1 answer
102 views

CRM and external systems: How to associate data with contacts?

This question is about Dynamics CRM but is valid for every system that allows merging entities. Having data related to a contact in multiple external systems, how would you know which contact the ...
Jan Sommer's user avatar
-1 votes
2 answers
210 views

Identifying similar customer data [duplicate]

I have a large database of customers. There's a need to identify customers who have two or more customer IDs. This comes mostly from people at the front-desk creating new customers instead of ...
azathoth's user avatar
  • 107
3 votes
1 answer
589 views

Reproducible uniqueness

So, I have a bunch of calls that are all being generated with a UUID1 throughout the day. At the end of the call the call is processed and some metrics around that call are generated and stored in ...
Jared Mackey's user avatar
22 votes
2 answers
11k views

Is there an elegant way to check unique constraints on domain object attributes without moving business logic into service layer?

I have been adapting domain-driven design for about 8 years now and even after all these years, there is still one thing, that has been bugging me. That is checking for a unique record in data storage ...
Andy's user avatar
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1647 votes
11 answers
828k views

Which hashing algorithm is best for uniqueness and speed?

Which hashing algorithm is best for uniqueness and speed? Example (good) uses include hash dictionaries. I know there are things like SHA-256 and such, but these algorithms are designed to be secure,...
Earlz's user avatar
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