CREATE, DROP, ALTER TABLE causes MDL BF-BF conflict #463
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Issue: ------ During DROP TABLE execution, if parent tables are opened and MDL locks for those tables are acquired, then concurrent operations to those table could end up in MDL conflict. For CREATE and ALTER TABLE foreign keys of immediate parent table are getting appended in certiification, but if parent table also has foreign key and if those refrenced tables are opened and MDL locks for those tables are acquired, then concurrent operations to those tables could also end up in MDL conflict. Solution: --------- To avoid MDL BF-BF conflicts, append certification keys for all parent's tables so that potentially conflicting operation are not applied in parallel with CREATE, DROP, ALTER TABLE command.
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Issue:
During DROP TABLE execution, if parent tables are opened and MDL locks for those tables are acquired, then concurrent operations to those table could end up in MDL conflict.
For CREATE and ALTER TABLE foreign keys of immediate parent table are getting appended in certiification, but if parent table also has foreign key and if those refrenced tables are opened and MDL locks for those tables are acquired, then concurrent operations to those tables could also end up in MDL conflict.
Solution:
To avoid MDL BF-BF conflicts, append certification keys for all parent's tables so that potentially conflicting operation are not applied in parallel with CREATE, DROP, ALTER TABLE command.