indexing
	description: "DB_SELECTION for dynamic sql"
	legal: "See notice at end of class."
	status: "See notice at end of class."
	date: "$Date: 2006-01-22 18:25:44 -0800 (Sun, 22 Jan 2006) $"
	revision: "$Revision: 56675 $"

class interface
	DB_DYN_SELECTION

create 
	make
			-- Create an interface objet to query active base.

feature -- Initialization

	make
			-- Create an interface objet to query active base.
	
feature -- Access

	generating_type: STRING_8
			-- Name of current object's generating type
			-- (type of which it is a direct instance)
			-- (from ANY)

	generator: STRING_8
			-- Name of current object's generating class
			-- (base class of the type of which it is a direct instance)
			-- (from ANY)

	last_parsed_query: STRING_8
			-- Last parsed SQL query
			-- (from DB_SELECTION)
	
feature -- Comparison

	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void
			-- or attached to isomorphic object structures?
			-- (from ANY)
		ensure -- from ANY
			shallow_implies_deep: standard_equal (some, other) implies Result
			both_or_none_void: (some = Void) implies (Result = (other = Void))
			same_type: (Result and (some /= Void)) implies some.same_type (other)
			symmetric: Result implies deep_equal (other, some)

	frozen equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached
			-- to objects considered equal?
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

	is_equal (other: like Current): BOOLEAN
			-- Is `other' attached to an object considered
			-- equal to current object?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			symmetric: Result implies other.is_equal (Current)
			consistent: standard_is_equal (other) implies Result

	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached to
			-- field-by-field identical objects of the same type?
			-- Always uses default object comparison criterion.
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

	frozen standard_is_equal (other: like Current): BOOLEAN
			-- Is `other' attached to an object of the same type
			-- as current object, and field-by-field identical to it?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			same_type: Result implies same_type (other)
			symmetric: Result implies other.standard_is_equal (Current)
	
feature -- Status report

	after: BOOLEAN
			-- Is the container after?
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			container_exists: container /= Void

	conforms_to (other: ANY): BOOLEAN
			-- Does type of current object conform to type
			-- of `other' (as per Eiffel: The Language, chapter 13)?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void

	container: LIST [DB_RESULT]
			-- Stored cursors.
			-- (from DB_SELECTION)

	cursor: DB_RESULT
			-- Cursor pointing to last fetched query result
			-- (from DB_SELECTION)

	ht: HASH_TABLE [ANY, STRING_8]
			-- Correspondence table between object references
			-- and mapped keys
			-- (from STRING_HDL)

	ht_order: ARRAYED_LIST [STRING_8]
			-- Keys of ht in order of mapping
			-- (from STRING_HDL)

	immediate_execution: BOOLEAN
			-- Are requests immediately executed?
			-- (default is `no').
			-- (from DB_EXEC_USE)

	is_allocatable: BOOLEAN
			-- Can `Current' be added to other concurrently opened selections?
			-- (from DB_SELECTION)

	is_executed: BOOLEAN
			-- Is the statement has been executed ?
			-- (from PARAMETER_HDL)

	is_exiting: BOOLEAN
			-- Is exit condition of load_result iteration loop met?
			-- (from DB_SELECTION)
		ensure -- from DB_SELECTION
			Result implies (not is_ok or else exhausted or else (stop_condition /= Void and then stop_condition.found))

	is_mapped (key: STRING_8): BOOLEAN
			-- Is `key' mapped to an Eiffel entity ?
			-- (from PARAMETER_HDL)
		require -- from STRING_HDL
			ht_not_void: ht /= Void
			keys_exists: key /= Void

	is_prepared: BOOLEAN
			-- Is the statement has been prepared ?
			-- (from PARAMETER_HDL)

	is_tracing: BOOLEAN
			-- Is trace option for SQL queries on?
			-- (from DB_EXEC_USE)

	last_query: STRING_8
			-- Last SQL statement used
			-- (from DB_EXPRESSION)

	mapped_value (key: STRING_8): ANY
			-- Value mapped with `key'
			-- (from PARAMETER_HDL)
		require -- from STRING_HDL
			ht_not_void: ht /= Void
			key_exists: key /= Void
			key_mapped: is_mapped (key)
		ensure -- from STRING_HDL
			result_exists: Result /= Void

	object: ANY
			-- Eiffel object to be filled in by cursor_to_object
			-- (from DB_SELECTION)

	parameter_name_exist (key: STRING_8): BOOLEAN
			-- (from PARAMETER_HDL)
		require -- from PARAMETER_HDL
			not_void: key /= Void

	same_type (other: ANY): BOOLEAN
			-- Is type of current object identical to type of `other'?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			definition: Result = (conforms_to (other) and other.conforms_to (Current))

	stop_condition: ACTION
			-- Object providing an execute routine called
			-- after each load_result iteration step
			-- (from DB_SELECTION)

	trace_output: FILE
			-- Trace destination file
			-- (from DB_EXEC_USE)
	
feature {ANY} -- Status report

	is_connected: BOOLEAN
			-- Has connection to the database server succeeded?
			-- (from DB_STATUS_USE)

	is_ok: BOOLEAN
			-- Is last SQL statement ok ?
			-- (from DB_STATUS_USE)
	
feature -- Status setting

	cursor_to_object
			-- Assign object attributes with cursor field values.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			cursor_exists: cursor /= Void
			object_exists: object /= Void

	forth
			-- Move cursor to next element of container.
			-- (from DB_SELECTION)
		require else -- from DB_SELECTION
			container_exists: container /= Void
		ensure then -- from DB_SELECTION
			container_index_moved: container.index = old container.index + 1
			cursor_updated: not after implies cursor = container.item

	no_object_convert
			-- Do not transform cursor into an Eiffel object
			-- while reading in selection results.
			-- (from DB_SELECTION)
		ensure -- from DB_SELECTION
			object = Void

	object_convert (ref: ANY)
			-- Set object with `reference', reference to an Eiffel 
			-- object to be filled in with cursor field values.
			-- Use this before load_result for performance.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			reference_exists: ref /= Void
		ensure -- from DB_SELECTION
			object_set: object = ref

	reset_cursor (c: DB_RESULT)
			-- Reset cursor with `c'.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			arguments_exists: c /= Void
			connected: is_connected
		ensure -- from DB_SELECTION
			cursor_reset: cursor = c

	set_action (action: ACTION)
			-- Set stop_condition with `action'.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			action_exists: action /= Void
		ensure -- from DB_SELECTION
			stop_condition_set: stop_condition = action

	set_container (one_container: like container)
			-- Make results of selection query persist in container.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			container_exists: one_container /= Void
		ensure -- from DB_SELECTION
			container_set: container = one_container

	set_immediate
			-- Set queries to be executed with a
			-- `EXECUTE IMMEDIATE' SQL  statement.
			-- (from DB_EXEC_USE)
		ensure -- from DB_EXEC_USE
			execution_status: immediate_execution

	set_query (query: STRING_8)
			-- Set last_query with query.
			-- (from DB_EXPRESSION)
		require -- from DB_EXPRESSION
			query_not_void: query /= Void
		ensure -- from DB_EXPRESSION
			last_query_changed: last_query = query

	set_trace
			-- Trace queries sent to database server.
			-- (from DB_EXEC_USE)
		ensure -- from DB_EXEC_USE
			trace_status: is_tracing

	start
			-- Set cursor on first element of container.
			-- (from DB_SELECTION)
		require else -- from DB_SELECTION
			container_exists: container /= Void
		ensure then -- from DB_SELECTION
			container_on_first: container.isfirst
			cursor_updated: cursor = container.item

	unset_action
			-- Reset stop_condition to Void.
			-- (from DB_SELECTION)
		ensure -- from DB_SELECTION
			stop_condition_void: stop_condition = Void

	unset_container
			-- Do not store in container results of selection.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			container_exists: container /= Void
		ensure -- from DB_SELECTION
			container_is_void: container = Void

	unset_immediate
			-- Set queries to be executed with a
			-- prepare followed by a execute SQL statement.
			-- (from DB_EXEC_USE)
		ensure -- from DB_EXEC_USE
			execution_status: not immediate_execution

	unset_trace
			-- Do not trace queries sent to database server.
			-- (from DB_EXEC_USE)
		ensure -- from DB_EXEC_USE
			trace_status: not is_tracing
	
feature -- Element change

	execute
			-- Execute the sql statement
		require
			prepared_statement: is_prepared
		ensure
			prepared_statement: is_executed

	parameter_count: INTEGER_32
		ensure -- from PARAMETER_HDL
			Result > 0 implies is_prepared

	prepare (s: STRING_8)
			-- Parse of the sql statement `s'
		require
			not_void: s /= Void
			meaning_full_statement: s.count > 0
			is_ok: is_ok
			is_allocatable: is_allocatable
		ensure
			prepared_statement: is_prepared
			prepared_statement: not is_executed
	
feature -- Duplication

	copy (other: like Current)
			-- Update current object using fields of object attached
			-- to `other', so as to yield equal objects.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_equal: is_equal (other)

	frozen deep_copy (other: like Current)
			-- Effect equivalent to that of:
			--		copy (`other' . deep_twin)
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			deep_equal: deep_equal (Current, other)

	frozen deep_twin: like Current
			-- New object structure recursively duplicated from Current.
			-- (from ANY)
		ensure -- from ANY
			deep_equal: deep_equal (Current, Result)

	frozen standard_copy (other: like Current)
			-- Copy every field of `other' onto corresponding field
			-- of current object.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_standard_equal: standard_is_equal (other)

	frozen standard_twin: like Current
			-- New object field-by-field identical to `other'.
			-- Always uses default copying semantics.
			-- (from ANY)
		ensure -- from ANY
			standard_twin_not_void: Result /= Void
			equal: standard_equal (Result, Current)

	frozen twin: like Current
			-- New object equal to `Current'
			-- twin calls copy; to change copying/twining semantics, redefine copy.
			-- (from ANY)
		ensure -- from ANY
			twin_not_void: Result /= Void
			is_equal: Result.is_equal (Current)
	
feature -- Basic operations

	frozen default: like Current
			-- Default value of object's type
			-- (from ANY)

	frozen default_pointer: POINTER
			-- Default value of type `POINTER'
			-- (Avoid the need to write `p'.default for
			-- some `p' of type `POINTER'.)
			-- (from ANY)

	default_rescue
			-- Process exception for routines with no Rescue clause.
			-- (Default: do nothing.)
			-- (from ANY)

	frozen do_nothing
			-- Execute a null action.
			-- (from ANY)

	execute_query
			-- Execute query with last_query.
			-- (from DB_SELECTION)
		require -- from DB_EXPRESSION
			last_query_not_void: last_query /= Void

	load_result
			-- Iterate through selection results,
			-- load container if requested and call action routine
			-- for each iteration step until `exit_condition' is met.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			connected: is_connected
			is_ok: is_ok
		ensure -- from DB_SELECTION
			cursor_not_void: cursor /= Void
			exit_condition_met: is_exiting

	next
			-- Move to next element matching the query.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			connected: is_connected

	query (s: STRING_8)
			-- Select stored objects using `s' and make
			-- them retrievable using load_result.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			connected: is_connected
			argument_exists: s /= Void
			argument_is_not_empty: not s.is_empty
			is_ok: is_ok
			is_allocatable: is_allocatable
		ensure -- from DB_SELECTION
			last_query_changed: last_query = s

	terminate
			-- Clear database cursor.
			-- (from DB_SELECTION)
		require -- from DB_SELECTION
			connected: is_connected
		ensure -- from DB_SELECTION
			is_allocatable: is_allocatable

	wipe_out
			-- Clear selection results.
			-- (from DB_SELECTION)
		ensure -- from DB_SELECTION
			container_is_empty: container /= Void implies container.is_empty
			object_model_void: object = Void
			cursor_void: cursor = Void
	
feature 

	clear_all
			-- (from PARAMETER_HDL)
		require -- from STRING_HDL
			ht_not_void: ht /= Void

	set_map_name (n: ANY; key: STRING_8)
			-- Store item `n' whith key `key'.
			-- (from PARAMETER_HDL)
		require -- from STRING_HDL
			ht_not_void: ht /= Void
			key_exists: key /= Void
			not_key_in_table: not is_mapped (key)
		ensure -- from STRING_HDL
			ht.count = old ht.count + 1

	unset_map_name (key: STRING_8)
			-- Remove item associated with key `key'.
			-- (from PARAMETER_HDL)
		require -- from STRING_HDL
			ht_not_void: ht /= Void
			key_exists: key /= Void
			item_exists: is_mapped (key)
		ensure -- from STRING_HDL
			ht.count = old ht.count - 1
	
feature -- Output

	io: STD_FILES
			-- Handle to standard file setup
			-- (from ANY)

	out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- Was declared in ANY as synonym of tagged_out.
			-- (from ANY)

	print (some: ANY)
			-- Write terse external representation of `some'
			-- on standard output.
			-- (from ANY)

	frozen tagged_out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- Was declared in ANY as synonym of out.
			-- (from ANY)
	
feature -- Platform

	operating_environment: OPERATING_ENVIRONMENT
			-- Objects available from the operating system
			-- (from ANY)
	
feature -- setting

	set_executed (b: BOOLEAN)
			-- (from PARAMETER_HDL)

	set_parameter (value: ANY; key: STRING_8)
			-- (from PARAMETER_HDL)
		require -- from PARAMETER_HDL
			key_not_void: key /= Void
			has_parameters: parameter_count > 0

	set_parameters_value (p: ARRAY [ANY])
			-- (from PARAMETER_HDL)
		require -- from PARAMETER_HDL
			has_parameters: parameter_count > 0

	set_prepared (b: BOOLEAN)
			-- (from PARAMETER_HDL)

	setup_parameters
			-- setup parameters_value with actual parameters value
			-- (from PARAMETER_HDL)
	
invariant
		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

indexing
	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
	source: "[
		Eiffel Software
		356 Storke Road, Goleta, CA 93117 USA
		Telephone 805-685-1006, Fax 805-685-6869
		Website http://www.eiffel.com
		Customer support http://support.eiffel.com
	]"

end -- class DB_DYN_SELECTION