DSIExtAbstractTopHandler Class Reference

Defines an abstract class to facilitate the process of passing down of a relational TOP operation. More...

Inherits Simba::SQLEngine::ITopHandler.

List of all members.

Public Member Functions

virtual SharedPtr
< DSIExtResultSet
Passdown (AETop *in_node)
 Pass down the given TOP operation.
virtual ~DSIExtAbstractTopHandler ()
 Destructor.

Protected Member Functions

 DSIExtAbstractTopHandler (SharedPtr< DSIExtResultSet > in_table)
 Constructor.
virtual SharedPtr
< DSIExtResultSet
PassdownSkipMTopN (SharedPtr< DSIExtResultSet > in_table, simba_uint64 in_skip, simba_uint64 in_limit)
 Pass down SKIP M TOP N operation.
virtual SharedPtr
< DSIExtResultSet
PassdownTopN (SharedPtr< DSIExtResultSet > in_table, simba_uint64 in_limit)
 Pass down TOP N operation to DSII.
virtual SharedPtr
< DSIExtResultSet
PassdownTopNPercent (SharedPtr< DSIExtResultSet > in_table, simba_double64 in_limit)=0
 Pass down TOP N PERCENT operation to DSII.

Detailed Description

Defines an abstract class to facilitate the process of passing down of a relational TOP operation.

This abstract class:

A relational TOP node has the operand on which the TOP operates and a value expression that represents the limit number of rows returned in the result set. This abstract handler converts the value expression into an integer and pass the integer and the operand to DSII.

The expected value expression is:


Constructor & Destructor Documentation

virtual ~DSIExtAbstractTopHandler (  )  [virtual]

Destructor.

DSIExtAbstractTopHandler ( SharedPtr< DSIExtResultSet in_table  )  [protected]

Constructor.

Parameters:
in_table The table on which the TOP N operates. Cannot be NULL.

Member Function Documentation

virtual SharedPtr<DSIExtResultSet> Passdown ( AETop in_node  )  [virtual]

Pass down the given TOP operation.

Parameters:
in_node The TOP operation node. Cannot be NULL. (NOT OWN)
Returns:
The table that represents TOP operation result if it is passed down successful, NULL otherwise.

Implements ITopHandler.

virtual SharedPtr<DSIExtResultSet> PassdownSkipMTopN ( SharedPtr< DSIExtResultSet in_table,
simba_uint64  in_skip,
simba_uint64  in_limit 
) [protected, virtual]

Pass down SKIP M TOP N operation.

Parameters:
in_table The table on which the SKIP M TOP N operates. Cannot be NULL.
in_skip The number of rows to skip before selecting TOP N
in_limit The limit number of rows returned in the result set.
Returns:
The table that represents SKIP M TOP N result if it is passed down successfully, NULL otherwise.
virtual SharedPtr<DSIExtResultSet> PassdownTopN ( SharedPtr< DSIExtResultSet in_table,
simba_uint64  in_limit 
) [protected, virtual]

Pass down TOP N operation to DSII.

Parameters:
in_table The table on which the TOP N operates. Cannot be NULL.
in_limit The limit number of rows returned in the result set.
Returns:
The table that represents TOP N result if it is passed down successful, NULL otherwise.
virtual SharedPtr<DSIExtResultSet> PassdownTopNPercent ( SharedPtr< DSIExtResultSet in_table,
simba_double64  in_limit 
) [protected, pure virtual]

Pass down TOP N PERCENT operation to DSII.

NOTE: This method is not called in DSIExtAbstractTopHandler as passing down top n percent is not supported.

Parameters:
in_table The table on which the TOP N operates. Cannot be NULL.
in_limit The number representing the percent of the row limit. Should be in the range [0, 100].
Returns:
The table that represents TOP N PERCENT result if it is passed down successful, NULL otherwise.

The documentation for this class was generated from the following file:

Generated on Wed May 17 14:21:17 2017 for SimbaEngine 10.1.3.1011 by simba