find_or_create_by causes SQLite3 PRIMARY KEY must be unique error

Question

I'm using ActiveRecord with Ruby (no Rails) to interface with a SQLite3 database. I fetch some data from a web API and store it in the database using find_or_create_by(some_hash). This works fine as long as the some_hash data is unique. If the some_hash already exists in the database, then the find_or_create_by method fails and gives the following sql error: SQLite3::ConstraintException: PRIMARY KEY must be unique.

I expected the find_or_create method first checks my database to see if the data already exists and if it does, then it will not create a duplicate entry. However if it doesn't find the data, then and only then it will create a new entry. So why do I get that error when some_hash already exists in the database like it was trying to save a duplicate entry?

How can I work around this issue?

Sherwyn Goh · Accepted Answer · 2014-01-30 09:11:07Z

1

I don't know why its throwing that error at you, but if you want you can just break the method upinto its constituents:

A.create(some_hash) unless A.where(some_hash).present?

Hope that helps

answered Jan 30, 2014 at 9:11

Sherwyn Goh

1,3521 gold badge10 silver badges19 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

HM1 · Accepted Answer · 2014-01-30 17:43:55Z

0

Here's what worked:

A.create(some_hash) unless A.where("id" => some_hash["id"]).exists?

For some reason, querying the database with some_hash resulted in false positives and therefore I had to explicitly specify just the id.

answered Jan 30, 2014 at 17:43

HM1

1,6842 gold badges18 silver badges25 bronze badges

Collectives™ on Stack Overflow

find_or_create_by causes SQLite3 PRIMARY KEY must be unique error

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related