Use empty? instead of count for validate uniqueness #2122
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Using `empty?` instead of `count` for performance reasons. The `empty?` checks for the existence of any record and is generally faster than `count`.
numbata
force-pushed
the
validate_uniqueness_by_finding_first_row
branch
from
03e510f
to
c457c1e
Compare
|
Thanks for the patch. This makes sense to me. I'll review and test later today. |
numbata
commented
Jan 19, 2024
| db = Sequel.mock(:fetch=>proc{|sql| sql =~ /'a{51}'|'uniq'/ ? {:v=>0} : {:v=>1}}) | ||
| fetch_proc = proc do |sql| | ||
| if sql =~ /'a{51}'|'uniq'/ | ||
| sql =~ /1 AS one/ ? {:v=>nil} : {:v=>0} |
There was a problem hiding this comment.
This is not a style change. The code was unwrapped because new check was added here.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Using
emptyprovides a more efficient way to check for records that violate the uniqueness constraint. Unlikecount, which counts all matching rows,emptystops as soon as it finds a match, thereby reducing the load on the database. This change is particularly beneficial for tables with a large number of rows, where performance can be an issue.