Module org.postgresql.pljava

Package org.postgresql.pljava

Interface ResultSetProvider

All Known Subinterfaces:

ResultSetProvider.Large

public interface ResultSetProvider

An implementation of this interface is returned from functions and procedures that are declared to return SET OF a complex type. This interface is appropriate when the function will be generating the returned set on the fly; if it will have a ResultSet obtained from a query, it should just return ResultSetHandle instead. Functions that return SET OF a simple type should simply return an Iterator.

For a function declared to return SETOF RECORD rather than a specific complex type known in advance, the receiver argument to assignRowValues can be queried to learn the number, names, and types of columns expected by the caller.

Author:

Thomas Hallgren

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	ResultSetProvider.Large	Version of ResultSetProvider where the assignRowValues method accepting a long row count must be implemented, and the int version defaults to using it.

Method Summary

Modifier and Type	Method	Description
boolean	assignRowValues(ResultSet receiver, int currentRow)	Older version where currentRow is limited to the range of int.
default boolean	assignRowValues(ResultSet receiver, long currentRow)	This method is called once for each row that should be returned from a procedure that returns a set of rows.
void	close()	Called after the last row has returned or when the query evaluator decides that it does not need any more rows.

Method Detail

assignRowValues

default boolean assignRowValues(ResultSet receiver,
                                long currentRow)
                         throws SQLException

This method is called once for each row that should be returned from a procedure that returns a set of rows. The receiver is a SingleRowWriter instance that is used to capture the data for the row.

If the return type is RECORD rather than a specific complex type, SQL requires a column definition list to follow any use of the function in a query. The ResultSetMetaData of receiver can be used here to learn the number, names, and types of the columns expected by the caller. (It can also be used in the case of a specific complex type, but in that case the names and types are probably already known.)

This default implementation calls assignRowValues(ResultSet,int), or throws an SQLException with SQLState 54000 (program limit exceeded) if the row number exceeds Integer.MAX_VALUE.

Parameters:

receiver - Receiver of values for the given row.

currentRow - Row number, zero on the first call, incremented by one on each subsequent call.

Returns:

true if a new row was provided, false if not (end of data).

Throws:

SQLException

assignRowValues

boolean assignRowValues(ResultSet receiver,
                        int currentRow)
                 throws SQLException

Older version where currentRow is limited to the range of int.

Throws:

SQLException

close

void close()
    throws SQLException

Called after the last row has returned or when the query evaluator decides that it does not need any more rows.

Throws:

SQLException