- 07 8月, 2016 2 次提交
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由 Xavier Noria 提交于
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由 Xavier Noria 提交于
The current code base is not uniform. After some discussion, we have chosen to go with double quotes by default.
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- 06 11月, 2015 2 次提交
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由 Sam Davies 提交于
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由 Sam Davies 提交于
- Addresses issue #12330 Overview ======== Cached postgres prepared statements become invalidated if the schema changes in a way that it affects the returned result. Examples: - adding or removing a column then doing a 'SELECT *' - removing the foo column then doing a 'SELECT bar.foo' In normal operation this isn't a problem, we can rescue the error, deallocate the prepared statement and re-issue the command. However in PostgreSQL transactions, once any command fails, the transaction becomes 'poisoned' and any subsequent commands will raise InFailedSQLTransaction. This includes DEALLOCATE statements, so the default deallocation strategy instead of removing the cached prepared statement instead raises InFailedSQLTransaction. Why this is bad =============== 1. InFailedSQLTransaction is a fairly cryptic error and doesn't communicate any useful information about what has actually gone wrong. 2. In the naive implementation the prepared statement never gets deallocated - it stays alive for the length of the session taking up memory on the postgres server. 3. It is unsafe to retry the transaction because the bad prepared statement is still in the cache and we would see the exact same failure repeated. Solution ======== If we are outside a transaction we can continue to handle these failures gracefully in the usual way. Inside a transaction instead of issuing a DEALLOCATE command that will certainly fail, we now raise ActiveRecord::PreparedStatementCacheExpired. This can be handled further up the stack, notably inside TransactionManager#within_new_transaction. Here we can make sure to first rollback the transaction, then safely issue DEALLOCATE statements to invalidate the rest of the cached prepared statements. This also allows the user (or some gem) the opportunity to catch this error and voluntarily retry the transaction if a schema change causes the prepared statement cache to become invalidated. Because the outdated statement has been deallocated, we can expect the transaction to succeed on the second try.
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- 17 3月, 2015 1 次提交
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由 Brandon Weiss 提交于
I’m renaming all instances of `use_transcational_fixtures` to `use_transactional_tests` and “transactional fixtures” to “transactional tests”. I’m deprecating `use_transactional_fixtures=`. So anyone who is explicitly setting this will get a warning telling them to use `use_transactional_tests=` instead. I’m maintaining backwards compatibility—both forms will work. `use_transactional_tests` will check to see if `use_transactional_fixtures` is set and use that, otherwise it will use itself. But because `use_transactional_tests` is a class attribute (created with `class_attribute`) this requires a little bit of hoop jumping. The writer method that `class_attribute` generates defines a new reader method that return the value being set. Which means we can’t set the default of `true` using `use_transactional_tests=` as was done previously because that won’t take into account anyone using `use_transactional_fixtures`. Instead I defined the reader method manually and it checks `use_transactional_fixtures`. If it was set then it should be used, otherwise it should return the default, which is `true`. If someone uses `use_transactional_tests=` then it will overwrite the backwards-compatible method with whatever they set.
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- 14 1月, 2014 2 次提交
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由 Aaron Patterson 提交于
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由 Aaron Patterson 提交于
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- 12 1月, 2014 1 次提交
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由 Aaron Patterson 提交于
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- 29 9月, 2012 1 次提交
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由 Jon Leighton 提交于
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