Inheritance diagram for sp_rcontext:

Classes
class	Handler_call_frame
class	sp_handler_entry
class	Sql_condition_info
Public Member Functions
bool	set_variable (THD thd, uint var_idx, Item *value)
Item *	get_item (uint var_idx) const
Item **	get_item_addr (uint var_idx) const
bool	set_return_value (THD thd, Item *return_value_item)
bool	is_return_value_set () const
bool	push_handler (sp_handler *handler, uint first_ip)
void	pop_handlers (sp_pcontext *current_scope)
const Sql_condition_info *	raised_condition () const
bool	handle_sql_condition (THD thd, uint ip, const sp_instr *cur_spi)
void	exit_handler (sp_pcontext *target_scope)
uint	get_last_handler_continue_ip () const
bool	push_cursor (sp_instr_cpush *i)
void	pop_cursors (uint count)
void	pop_all_cursors ()
sp_cursor *	get_cursor (uint i) const
bool	set_case_expr (THD thd, int case_expr_id, Item *case_expr_item_ptr)
Item *	get_case_expr (int case_expr_id) const
Item **	get_case_expr_addr (int case_expr_id) const
Static Public Member Functions
static sp_rcontext *	create (THD thd, const sp_pcontext root_parsing_ctx, Field *return_value_fld)
Public Attributes
Query_arena *	callers_arena
bool	end_partial_result_set
sp_head *	sp
	The stored program for which this runtime context is created.

Member Function Documentation

sp_rcontext * sp_rcontext::create	(	THD *	thd,
		const sp_pcontext *	root_parsing_ctx,
		Field *	return_value_fld
	)		`[static]`

Construct and properly initialize a new sp_rcontext instance. The static create-function is needed because we need a way to return an error from the constructor.

Parameters:

thd	Thread handle.
root_parsing_ctx	Top-level parsing context for this stored program.
return_value_fld	Field object to store the return value (for stored functions only).

Returns:: valid sp_rcontext object or NULL in case of OOM-error.

void sp_rcontext::exit_handler ( sp_pcontext * target_scope )

Handle return from SQL-handler.

Parameters:

target_scope The BEGIN..END block, containing the target (next) instruction.

uint sp_rcontext::get_last_handler_continue_ip ( ) const [inline]

Returns:: the continue instruction pointer if the last activated CONTINUE handler. This function must not be called for the EXIT handlers.

bool sp_rcontext::handle_sql_condition	(	THD *	thd,
		uint *	ip,
		const sp_instr *	cur_spi
	)

Handle current SQL condition (if any).

This is the public-interface function to handle SQL conditions in stored routines.

Parameters:

thd	Thread handle.
ip[out]	Instruction pointer to the first handler instruction.
cur_spi	Current SP instruction.

Return values:

true	if an SQL-handler has been activated. That means, all of the following conditions are satisfied: the SP-instruction raised SQL-condition(s), and there is an SQL-handler to process at least one of those SQL-conditions, and that SQL-handler has been activated. Note, that the return value has nothing to do with "error flag" semantics.
false	otherwise.

void sp_rcontext::pop_cursors ( uint count )

Pop and delete given number of sp_cursor instance from the cursor stack.

Parameters:

count Number of cursors to pop & delete.

void sp_rcontext::pop_handlers ( sp_pcontext * current_scope )

Pop and delete given number of sp_handler_entry instances from the handler call stack.

Parameters:

current_scope The current BEGIN..END block.

bool sp_rcontext::push_cursor ( sp_instr_cpush * i )

Create a new sp_cursor instance and push it to the cursor stack.

Parameters:

i	Cursor-push instruction.

Returns:: error flag.

Return values:

false	on success.
true	on error.

bool sp_rcontext::push_handler	(	sp_handler *	handler,
		uint	first_ip
	)

Create a new sp_handler_entry instance and push it to the handler call stack.

Parameters:

handler	SQL-handler object.
first_ip	First instruction pointer of the handler.

Returns:: error flag.

Return values:

false	on success.
true	on error.

bool sp_rcontext::set_case_expr	(	THD *	thd,
		int	case_expr_id,
		Item **	case_expr_item_ptr
	)

Set CASE expression to the specified value.

Parameters:

thd	Thread handler.
case_expr_id	The CASE expression identifier.
case_expr_item	The CASE expression value

Returns:: error flag.

Return values:

false	on success.
true	on error.

Note:: The idea is to reuse Item_cache for the expression of the one CASE statement. This optimization takes place when there is CASE statement inside of a loop. So, in other words, we will use the same object on each iteration instead of creating a new one for each iteration.

TODO Hypothetically, a type of CASE expression can be different for each iteration. For instance, this can happen if the expression contains a session variable (something like @VAR) and its type is changed from one iteration to another.

In order to cope with this problem, we check type each time, when we use already created object. If the type does not match, we re-create Item. This also can (should?) be optimized.

Member Data Documentation

Query_arena* sp_rcontext::callers_arena

Arena used to (re) allocate items on. E.g. reallocate INOUT/OUT SP-variables when they don't fit into prealloced items. This is common situation with String items. It is used mainly in sp_eval_func_item().

bool sp_rcontext::end_partial_result_set

Flag to end an open result set before start executing an SQL-handler (if one is found). Otherwise the client will hang due to a violation of the client/server protocol.

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

sp_rcontext.h
sp_rcontext.cc

Classes

Public Member Functions

Static Public Member Functions

Public Attributes

Member Function Documentation

Member Data Documentation