Probability of collision when using a 32 bit hash

algorithm hash collision probability crc
nguyenngoc101 picture nguyenngoc101 · Jan 8, 2013 · Viewed 39.8k times · Source

I have a 10 character string key field in a database. I've used CRC32 to hash this field but I'm worry about duplicates. Could somebody show me the probability of collision in this situation?

p.s. my string field is unique in the database. If the number of string fields is 1 million, what is probability of collision ?

Answer

Adam Morris picture Adam Morris · Jan 8, 2013

Duplicate of Expected collisions for perfect 32bit crc

The answer referenced this article: http://arstechnica.com/civis/viewtopic.php?f=20&t=149670

Found the image below from: http://preshing.com/20110504/hash-collision-probabilities

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