| Aspect | Feature Selection | Feature Engineering |
| Purpose | Choose relevant features | Create informative features |
| Objective | Improve model performance by eliminating irrelevant or redundant features | Improve model's ability to capture patterns and relationships |
| Techniques | Correlation analysis, mutual information, feature importance scores, recursive feature elimination | Scaling, one-hot encoding, interaction terms, mathematical operations, date-related feature extraction |
| Automation | Can often be automated using statistical methods and algorithms | May require domain knowledge and human expertise |
| Examples | SelectKBest, SelectFromModel, Recursive Feature Elimination (RFE) | One-hot encoding, polynomial feature creation, date-related feature extraction |
Logged operations are replicated. These include, but are not limited to: DDL DML Create/alter table space Create/alter storage group Create/alter buffer pool XML data. Logged LOBs Not logged operations are not replicated. These include, but are not limited to: Database configuration parameters (this allows primary and standby databases to be configured differently). "Not logged initially" tables Not logged LOBs UDF (User Defined Function) libraries. UDF DDL is replicated. But the libraries used by UDF (such as C or Java libraries) are not replicated, because they are not stored in the database. Users must manually copy the libraries to the standby. Note: You can use database configuration parameter BLOCKNONLOGGED to block not logged operations on the primary.
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