Inheritance diagram for Item_func_set_user_var:

Public Member Functions
	Item_func_set_user_var (Name_string a, Item *b, bool delayed)
	Item_func_set_user_var (THD thd, Item_func_set_user_var item)
enum Functype	functype () const
double	val_real ()
longlong	val_int ()
String *	val_str (String *str)
my_decimal *	val_decimal (my_decimal *)
double	val_result ()
longlong	val_int_result ()
bool	val_bool_result ()
String *	str_result (String *str)
my_decimal *	val_decimal_result (my_decimal *)
bool	is_null_result ()
bool	update_hash (void ptr, uint length, enum Item_result type, const CHARSET_INFO cs, Derivation dv, bool unsigned_arg)
bool	send (Protocol protocol, String str_arg)
void	make_field (Send_field *tmp_field)
bool	check (bool use_result_field)
void	save_item_result (Item *item)
	Evaluate and store item's result. This function is invoked on "SELECT ... INTO @var ...".
bool	update ()
enum Item_result	result_type () const
bool	fix_fields (THD thd, Item *ref)
void	fix_length_and_dec ()
virtual void	print (String *str, enum_query_type query_type)
void	print_assignment (String *str, enum_query_type query_type)
const char *	func_name () const
type_conversion_status	save_in_field (Field *field, bool no_conversions, bool can_use_result_field)
type_conversion_status	save_in_field (Field *field, bool no_conversions)
void	save_org_in_field (Field *field)
bool	register_field_in_read_map (uchar *arg)
bool	set_entry (THD *thd, bool create_if_not_exists)
void	cleanup ()
Public Attributes
Name_string	name
longlong	vint
double	vreal
String *	vstr
my_decimal *	vdec

Member Function Documentation

bool Item_func_set_user_var::check ( bool use_result_field )

This functions is invoked on SET @variable or @variable:= expression.

Evaluate (and check expression), store results.

Note:: For now it always return OK. All problem with value evaluating will be caught by thd->is_error() check in sql_set_variables().

Return values:

FALSE OK.

void Item_func_set_user_var::print	(	String *	str,
		enum_query_type	query_type
	)		`[virtual]`

This method is used for to:

to generate a view definition query (SELECT-statement);
to generate a SQL-query for EXPLAIN EXTENDED;
to generate a SQL-query to be shown in INFORMATION_SCHEMA;
debug.

For more information about view definition query, INFORMATION_SCHEMA query and why they should be generated from the Item-tree,

See also:: mysql_register_view().

Reimplemented from Item_func.

type_conversion_status Item_func_set_user_var::save_in_field	(	Field *	field,
		bool	no_conversions
	)		`[inline, virtual]`

Save a temporal value in packed longlong format into a Field. Used in optimizer.

Parameters:

OUT	field The field to set the value to.

Return values:

0	On success.
>0	In error.

Reimplemented from Item.

void Item_func_set_user_var::save_item_result ( Item * item )

Evaluate and store item's result. This function is invoked on "SELECT ... INTO @var ...".

Parameters:

item	An item to get value from.

bool Item_func_set_user_var::send	(	Protocol *	protocol,
		String *	buffer
	)		`[virtual]`

This is only called from items that is not of type item_field.

Reimplemented from Item.

bool Item_func_set_user_var::update ( )

This functions is invoked on SET @variable or @variable:= expression.

Note:: We have to store the expression as such in the variable, independent of the value method used by the user

Return values:

0	OK
1	EOM Error

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

Public Member Functions

Public Attributes

Member Function Documentation