| Interface | Description | 
|---|---|
| Optimizer | 
 Interface Optimizer wraps information returned from query optimizer. 
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| QueryOptimizer | 
 Sometimes you may want to optimize the sql statement before it is sent to DB. 
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| Class | Description | 
|---|---|
| ColumnInfo | 
 Interface ColumnInfo wraps column information, such as mapping name and column index in the sql statement. 
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| ConnectionInfo | 
 Class ConnectionInfo wraps all information used to create the connection to a database by JDBC driver. 
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| QueryInfo | 
 Class QueryInfo wraps information that a query optimizer needs. 
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