Don't Hide Internal Tables #70574
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Don't Hide Internal Tables #70574
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We override `table_exists` for our temporary mock dashboard database, but this also ends up overriding the check for tables that we don't consider temporary; most notably, the schema migrations table. This has worked up until now because Rails in versions earlier than 7.0 has a small bug in that it actually checks for the presence of the schema migrations table in the schema cache rather than checking for the actual table. This [was fixed in Rails 7.0](rails/rails#43877), which caused our tests to start failing with: Minitest::UnexpectedError: ActiveRecord::RecordNotUnique: Mysql2::Error: Duplicate entry '20260120193121' for key 'schema_migrations.PRIMARY' As they attempted to recreate a table which already exists. The simple fix is to update our override logic to return the correct result when checking for the existence of these tables.
Hamms
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Rails Upgrade
cat5inthecradle
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Jan 30, 2026
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We override
table_existsfor our temporary mock dashboard database, but this also ends up overriding the check for tables that we don't consider temporary; most notably, the schema migrations table. This has worked up until now because Rails in versions earlier than 7.0 has a small bug in that it actually checks for the presence of the schema migrations table in the schema cache rather than checking for the actual table.This was fixed in Rails 7.0, which caused our tests to start failing with:
As they attempted to recreate a table which already exists.
The simple fix is to update our override logic to return the correct result when checking for the existence of these tables.