Improve the implementation of prepared statement. #1518
Closed
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Outdated suggestions cannot be applied.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.
Motivation:
The implementation of prepared statement tries to accomodate both a lazy mode and a non lazy one, leading to the utilization of a future to unify the obtention of the prepared statement.
This is clearly suboptimal for the common case, since lazy prepared statement is only necessary when meeting indeterminate prepared statement (ambiguous) that requires a tuple for an actual preparation.
In addition the execution is done using a context comparison which fails when on a duplicated context.
Changes:
Use the context in thread comparison instead of context equality.
Make a prepared statement base which has two implementations lazy/direct which are both optimized for their specific cases.