A common problem with dynamic SQL is parsing performance in production. What makes matters worse is that many developers do not have access to production environments, so they are unaware of the problem (even if there's nothing new about this topic). What exactly is the problem?
Execution Plan CachesMost database vendors these days ship with an execution plan cache (Oracle calls it cursor cache), where previously parsed SQL statements are stored and their execution plans are cached for reuse. This is the main reason why bind variables are so important (the other reason being SQL injection prevention). By using bind variables, we can make sure that the database will easily recognize an identical SQL statement from a previous execution and be able to re-execute the previously found execution plan.
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