Drizzled Public API Documentation

drizzled::Item_aggregate_ref Class Reference
Inheritance diagram for drizzled::Item_aggregate_ref:
drizzled::Item_ref drizzled::Item_ident drizzled::Item drizzled::memory::SqlAlloc

Public Types

enum  Ref_Type { REF, DIRECT_REF, OUTER_REF }
enum  Type {
  FIELD_ITEM = 0, FUNC_ITEM, SUM_FUNC_ITEM, STRING_ITEM,
  INT_ITEM, REAL_ITEM, NULL_ITEM, VARBIN_ITEM,
  COPY_STR_ITEM, FIELD_AVG_ITEM, DEFAULT_VALUE_ITEM, PROC_ITEM,
  COND_ITEM, REF_ITEM, FIELD_STD_ITEM, FIELD_VARIANCE_ITEM,
  INSERT_VALUE_ITEM, SUBSELECT_ITEM, ROW_ITEM, CACHE_ITEM,
  TYPE_HOLDER, PARAM_ITEM, BOOLEAN_ITEM, DECIMAL_ITEM
}
enum  traverse_order { T_POSTFIX, T_PREFIX }
enum  cond_result { COND_UNDEF, COND_OK, COND_TRUE, COND_FALSE }

Public Member Functions

 Item_aggregate_ref (Name_resolution_context *context_arg, Item **item, const char *table_name_arg, const char *field_name_arg)
virtual void print (String *str)
enum Type type () const
bool eq (const Item *item, bool binary_cmp) const
double val_real ()
int64_t val_int ()
type::Decimalval_decimal (type::Decimal *)
bool val_bool ()
Stringval_str (String *tmp)
bool is_null ()
bool get_date (type::Time &ltime, uint32_t fuzzydate)
double val_result ()
int64_t val_int_result ()
Stringstr_result (String *tmp)
type::Decimalval_decimal_result (type::Decimal *)
bool val_bool_result ()
void send (plugin::Client *client, String *tmp)
void make_field (SendField *field)
bool fix_fields (Session *, Item **)
void fix_after_pullout (Select_Lex *new_parent, Item **ref)
int save_in_field (Field *field, bool no_conversions)
void save_org_in_field (Field *field)
enum Item_result result_type () const
enum_field_types field_type () const
Fieldget_tmp_table_field ()
Itemget_tmp_table_item (Session *session)
table_map used_tables () const
void update_used_tables ()
table_map not_null_tables () const
void set_result_field (Field *field)
bool is_result_field ()
void save_in_result_field (bool no_conversions)
Itemreal_item (void)
const Itemreal_item (void) const
bool walk (Item_processor processor, bool walk_subquery, unsigned char *arg)
bool result_as_int64_t ()
void cleanup ()
virtual Ref_Type ref_type ()
uint32_t cols ()
Itemelement_index (uint32_t i)
Item ** addr (uint32_t i)
bool check_cols (uint32_t c)
bool null_inside ()
void bring_value ()
bool basic_const_item () const
const char * full_name () const
bool remove_dependence_processor (unsigned char *arg)
virtual bool change_context_processor (unsigned char *cntx)
bool is_unsigned () const
virtual bool negative () const
void set_name (str_ref arg)
void set_name (const char *arg)
void set_name (const char *str, uint32_t length, const charset_info_st *cs=system_charset_info)
void init_make_field (SendField *tmp_field, enum_field_types type)
Fieldmake_string_field (Table *table)
void quick_fix_field ()
virtual int save_safe_in_field (Field *field)
virtual Item_result cast_to_int_type () const
virtual enum_field_types string_field_type () const
virtual int64_t val_int_endpoint (bool left_endp, bool *incl_endp)
uint64_t val_uint ()
Stringval_string_from_real (String *str)
Stringval_string_from_int (String *str)
Stringval_string_from_decimal (String *str)
type::Decimalval_decimal_from_real (type::Decimal *decimal_value)
type::Decimalval_decimal_from_int (type::Decimal *decimal_value)
type::Decimalval_decimal_from_string (type::Decimal *decimal_value)
type::Decimalval_decimal_from_date (type::Decimal *decimal_value)
type::Decimalval_decimal_from_time (type::Decimal *decimal_value)
int64_t val_int_from_decimal ()
double val_real_from_decimal ()
bool save_time_in_field (Field *field)
bool save_date_in_field (Field *field)
int save_str_value_in_field (Field *field, String *result)
virtual Fieldtmp_table_field (Table *t_arg)
virtual Itemclone_item ()
virtual cond_result eq_cmp_result () const
uint32_t float_length (uint32_t decimals_par) const
virtual uint32_t decimal_precision () const
int decimal_int_part () const
virtual bool const_item () const
virtual bool const_during_execution () const
void print_item_w_name (String *)
virtual void split_sum_func (Session *session, Item **ref_pointer_array, List< Item > &fields)
void split_sum_func (Session *session, Item **ref_pointer_array, List< Item > &fields, Item **ref, bool skip_registered)
virtual bool get_time (type::Time &ltime)
virtual bool get_date_result (type::Time &ltime, uint32_t fuzzydate)
virtual void update_null_value ()
virtual void top_level_item (void)
virtual bool is_bool_func (void)
virtual void no_rows_in_result (void)
virtual Itemcopy_or_same (Session *session)
virtual Itemcopy_andor_structure (Session *session)
virtual const charset_info_stcompare_collation ()
virtual Itemtransform (Item_transformer transformer, unsigned char *arg)
virtual Itemcompile (Item_analyzer analyzer, unsigned char **arg_p, Item_transformer transformer, unsigned char *arg_t)
virtual void traverse_cond (Cond_traverser traverser, void *arg, traverse_order order)
virtual bool collect_item_field_processor (unsigned char *arg)
virtual bool find_item_in_field_list_processor (unsigned char *arg)
virtual bool register_field_in_read_map (unsigned char *arg)
virtual bool subst_argument_checker (unsigned char **arg)
virtual bool cache_const_expr_analyzer (unsigned char **arg)
virtual Itemcache_const_expr_transformer (unsigned char *arg)
virtual Itemequal_fields_propagator (unsigned char *arg)
virtual bool set_no_const_sub (unsigned char *arg)
virtual Itemreplace_equal_field (unsigned char *arg)
Fieldtmp_table_field_from_field_type (Table *table, bool fixed_length)
virtual Itemneg_transformer (Session *session)
virtual Itemupdate_value_transformer (unsigned char *select_arg)
virtual Itemsafe_charset_converter (const charset_info_st *const tocs)
void delete_self ()
bool is_datetime ()
virtual bool is_expensive ()
Stringcheck_well_formed_result (String *str, bool send_error=0)
bool eq_by_collation (Item *item, bool binary_cmp, const charset_info_st *const cs)
uint32_t char_to_byte_length_safe (uint32_t char_length_arg, uint32_t mbmaxlen_arg)
uint32_t max_char_length () const
void fix_char_length (uint32_t max_char_length_arg)

Static Public Member Functions

static const charset_info_stdefault_charset ()
static void * operator new (size_t size)
static void * operator new (size_t size, Root &root)
static void * operator new (size_t size, Root *root)
static void * operator new[] (size_t size)
static void * operator new[] (size_t size, Root &root)
static void * operator new[] (size_t size, Root *root)
static void operator delete (void *)
static void operator delete (void *, Root &)
static void operator delete (void *, Root *)
static void operator delete[] (void *)
static void operator delete[] (void *, Root &)
static void operator delete[] (void *, Root *)

Public Attributes

Fieldresult_field
Item ** ref
Name_resolution_contextcontext
const char * db_name
const char * table_name
const char * field_name
bool alias_name_used
uint32_t cached_field_index
TableListcached_table
Select_Lex * depended_from
String str_value
const char * name
uint32_t name_length
Itemnext
uint32_t max_length
int8_t marker
uint8_t decimals
bool fixed
bool maybe_null
bool null_value
bool unsigned_flag
bool with_sum_func
bool is_autogenerated_name
bool with_subselect
DTCollation collation
Item_result cmp_context

Protected Member Functions

void set_properties ()
SessiongetSession ()

Protected Attributes

const char * orig_db_name
const char * orig_table_name
const char * orig_field_name

Detailed Description

Definition at line 700 of file item.cc.

Member Function Documentation

bool drizzled::Item_ref::basic_const_item ( ) const
inlinevirtualinherited

Returns true if this is a simple constant item like an integer, not a constant expression. Used in the optimizer to propagate basic constants.

Reimplemented from drizzled::Item.

Definition at line 150 of file ref.h.

bool drizzled::Item::cache_const_expr_analyzer ( unsigned char **  arg)
virtualinherited

Check if an item is a constant one and can be cached.

Parameters
arg[out] TRUE <=> Cache this item.
Returns
TRUE Go deeper in item tree.
FALSE Don't go deeper in item tree.

Definition at line 1262 of file item.cc.

References drizzled::Item::basic_const_item(), and drizzled::Item::const_item().

Referenced by drizzled::Join::cache_const_exprs().

Item * drizzled::Item::cache_const_expr_transformer ( unsigned char *  arg)
virtualinherited

Cache item if needed.

Parameters
argTRUE <=> Cache this item.
Returns
cache if cache needed.
this otherwise.

Definition at line 1297 of file item.cc.

Referenced by drizzled::Join::cache_const_exprs().

Item * drizzled::Item::compile ( Item_analyzer  analyzer,
unsigned char **  arg_p,
Item_transformer  transformer,
unsigned char *  arg_t 
)
virtualinherited

This function performs a generic "compilation" of the Item tree. The process of compilation is assumed to go as follows:

{
if (this->*some_analyzer(...))
{
compile children if any;
this->*some_transformer(...);
}
}

i.e. analysis is performed top-down while transformation is done bottom-up.

Reimplemented in drizzled::Item_cond, and drizzled::Item_func.

Definition at line 585 of file item.cc.

Referenced by drizzled::build_equal_items_for_cond(), drizzled::Join::cache_const_exprs(), and drizzled::Item_func::compile().

virtual bool drizzled::Item::const_during_execution ( ) const
inlinevirtualinherited

Returns true if this is constant but its value may be not known yet. (Can be used for parameters of prep. stmts or of stored procedures.)

Reimplemented in drizzled::Item_sum.

Definition at line 503 of file item.h.

bool drizzled::Item_ref::eq ( const Item item,
bool  binary_cmp 
) const
inlinevirtualinherited

Compares this Item to another Item, returning true if Item's are functionally equal.

This function is called when:

  • Comparing items in the WHERE clause (when doing where optimization)
  • When trying to find an order_st BY/GROUP BY item in the SELECT part

Reimplemented from drizzled::Item.

Definition at line 61 of file ref.h.

References drizzled::Item::eq().

bool drizzled::Item::eq_by_collation ( Item item,
bool  binary_cmp,
const charset_info_st *const  cs 
)
inherited

Compares two items using a given collation

This method works exactly as Item::eq if the collation cs coincides with the collation of the compared objects. Otherwise, first the collations that differ from cs are replaced for cs and then the items are compared by Item::eq. After the comparison the original collations of items are restored.

Parameters
Pointerto the item to compare with
Compareas binary?
Pointerto the collation to use when comparing strings
Return values
trueif compared items has been detected as equal
falseotherwise

Definition at line 1081 of file item.cc.

References drizzled::Item::eq().

void drizzled::Item_ref::fix_after_pullout ( Select_Lex *  new_parent,
Item **  ref 
)
virtualinherited

Fix after some tables has been pulled out. Basically re-calculate all attributes that are dependent on the tables.

Reimplemented from drizzled::Item.

Reimplemented in drizzled::Item_outer_ref.

Definition at line 569 of file ref.cc.

bool drizzled::Item_ref::fix_fields ( Session session,
Item **  reference 
)
virtualinherited

Resolve the name of a reference to a column reference.

The method resolves the column reference represented by 'this' as a column present in one of: GROUP BY clause, SELECT clause, outer queries. It is used typically for columns in the HAVING clause which are not under aggregate functions.

POSTCONDITION
Item_ref::ref is 0 or points to a valid item.

Note
The name resolution algorithm used is (where [T_j] is an optional table name that qualifies the column name):
resolve_extended([T_j].col_ref_i)
{
Search for a column or derived column named col_ref_i [in table T_j]
in the SELECT and GROUP clauses of Q.
if such a column is NOT found AND // Lookup in outer queries.
there are outer queries
{
for each outer query Q_k beginning from the inner-most one
{
Search for a column or derived column named col_ref_i
[in table T_j] in the SELECT and GROUP clauses of Q_k.
if such a column is not found AND
- Q_k is not a group query AND
- Q_k is not inside an aggregate function
OR
- Q_(k-1) is not in a HAVING or SELECT clause of Q_k
{
search for a column or derived column named col_ref_i
[in table T_j] in the FROM clause of Q_k;
}
}
}
}


This procedure treats GROUP BY and SELECT clauses as one namespace for column references in HAVING. Notice that compared to Item_field::fix_fields, here we first search the SELECT and GROUP BY clauses, and then we search the FROM clause.

Parameters
[in]sessioncurrent thread
[in,out]referenceview column if this item was resolved to a view column
Todo:
Here we could first find the field anyway, and then test this condition, so that we can give a better error message - ER_WRONG_FIELD_WITH_GROUP, instead of the less informative ER_BAD_FIELD_ERROR which we produce now.
Return values
trueif error
falseon success

Reimplemented from drizzled::Item.

Reimplemented in drizzled::Item_outer_ref.

Definition at line 113 of file ref.cc.

References drizzled::Item::fixed, drizzled::Table::map, drizzled::mark_as_dependent(), drizzled::Item::name, drizzled::Name_resolution_context::outer_context, drizzled::Name_resolution_context::resolve_in_select_list, drizzled::resolve_ref_in_select_and_group(), drizzled::Name_resolution_context::select_lex, and drizzled::TableList::select_lex.

Referenced by drizzled::Item_field::fix_fields(), and drizzled::Item_field::fix_outer_field().

bool drizzled::Item_ref::get_date ( type::Time ltime,
uint32_t  fuzzydate 
)
virtualinherited

Get the value of the function as a type::Time structure. As a extra convenience the time structure is reset on error!

Reimplemented from drizzled::Item.

Reimplemented in drizzled::Item_direct_ref, and drizzled::Item_ref_null_helper.

Definition at line 513 of file ref.cc.

References drizzled::Item::null_value.

bool drizzled::Item::get_time ( type::Time ltime)
virtualinherited

Get time of first argument.

As a extra convenience the time structure is reset on error!

Reimplemented in drizzled::Item_date_typecast, drizzled::Item_field, drizzled::function::cast::Time, and drizzled::Item_func_curtime.

Definition at line 494 of file item.cc.

References drizzled::Item::val_str().

Referenced by drizzled::Item::send().

bool drizzled::Item::is_expensive ( )
virtualinherited

Tests whether an expression is expensive to compute. Used during optimization to avoid computing expensive expressions during this phase. Also used to force temp tables when sorting on expensive functions.

Todo:

Normally we should have a method: cost Item::execution_cost(), where 'cost' is either 'double' or some structure of various cost parameters.

*NOTE This function is now used to prevent evaluation of materialized IN subquery predicates before it is allowed. grep for DontEvaluateMaterializedSubqueryTooEarly to see the uses.

Definition at line 688 of file item.cc.

Referenced by drizzled::Join::optimize().

bool drizzled::Item_ref::is_null ( )
virtualinherited

The method allows to determine nullness of a complex expression without fully evaluating it, instead of calling val/result*() then checking null_value. Used in Item_func_isnull/Item_func_isnotnull and Item_sum_count/Item_sum_count_distinct. Any new item which can be NULL must implement this method.

Reimplemented from drizzled::Item.

Reimplemented in drizzled::Item_direct_ref.

Definition at line 506 of file ref.cc.

References drizzled::Item::fixed.

Field * drizzled::Item::make_string_field ( Table table)
inherited

Create a field to hold a string value from an item.

If max_length > CONVERT_IF_BIGGER_TO_BLOB create a blob
If max_length > 0 create a varchar
If max_length == 0 create a CHAR(0)

Parameters
tableTable for which the field is created

Definition at line 1103 of file item.cc.

References drizzled::Item::maybe_null, and drizzled::Item::name.

Referenced by drizzled::create_tmp_field_from_item(), and drizzled::Item::tmp_table_field_from_field_type().

void drizzled::Item::no_rows_in_result ( void  )
virtualinherited
table_map drizzled::Item_ref::not_null_tables ( ) const
inlinevirtualinherited

Return table map of tables that can't be NULL tables (tables that are used in a context where if they would contain a NULL row generated by a LEFT or RIGHT join, the item would not be true). This expression is used on WHERE item to determinate if a LEFT JOIN can be converted to a normal join. Generally this function should return used_tables() if the function would return null if any of the arguments are null As this is only used in the beginning of optimization, the value don't have to be updated in update_used_tables()

Reimplemented from drizzled::Item.

Definition at line 98 of file ref.h.

virtual void drizzled::Item_aggregate_ref::print ( String str)
inlinevirtual

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
register_view().

Reimplemented from drizzled::Item_ref.

Definition at line 707 of file item.cc.

void drizzled::Item::quick_fix_field ( )
inlineinherited

Should be used in case where we are sure that we do not need complete fix_fields() procedure.

Definition at line 207 of file item.h.

Referenced by drizzled::build_equal_items_for_cond(), drizzled::check_row_equality(), drizzled::check_simple_equality(), drizzled::eliminate_item_equal(), and drizzled::Join::exec().

bool drizzled::Item_ref::result_as_int64_t ( )
inlinevirtualinherited

Returns true for Items representing DATE/TIME functions and DATE/TIME table fields. Those Items have result_type()==STRING_RESULT (and not INT_RESULT), but their values should be compared as integers (because the integer representation is more precise than the string one).

Reimplemented from drizzled::Item.

Definition at line 116 of file ref.h.

int drizzled::Item::save_str_value_in_field ( Field field,
String result 
)
inherited

Stores a string value in field directly

The method is used by Item_*::save_in_field implementations when we don't need to calculate the value to store

See Also
Item_string::save_in_field() implementation for example
Parameters
Pointerto field where to store
Pointerto the string value to be stored
Return values
Nonzerovalue if error

Check if the Item is null and stores the NULL or the result value in the field accordingly.

Definition at line 272 of file item.cc.

void drizzled::Item_ref::send ( plugin::Client client,
String str 
)
virtualinherited

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

Reimplemented from drizzled::Item.

Definition at line 378 of file ref.cc.

void drizzled::Item_ref::set_result_field ( Field field)
inlinevirtualinherited

Sets field of temporary table for Item which can be switched on temporary table during query processing (grouping and so on)

Reimplemented from drizzled::Item.

Definition at line 99 of file ref.h.

void drizzled::Item::split_sum_func ( Session session,
Item **  ref_pointer_array,
List< Item > &  fields,
Item **  ref,
bool  skip_registered 
)
inherited

Move SUM items out from item tree and replace with reference.

Parameters
sessionThread handler
ref_pointer_arrayPointer to array of reference fields
fieldsAll fields in select
refPointer to item
skip_registered<=> function be must skipped for registered SUM items
Note
This is from split_sum_func() for items that should be split

All found SUM items are added FIRST in the fields list and we replace the item with a reference.

session->fatal_error() may be called if we are out of memory

Definition at line 716 of file item.cc.

References drizzled::Item::name, and drizzled::Item::used_tables().

Field * drizzled::Item::tmp_table_field_from_field_type ( Table table,
bool  fixed_length 
)
inherited

Create a field based on field_type of argument.

For now, this is only used to create a field for IFNULL(x,something) and time functions

Return values
NULLerror
\::Created field

Definition at line 1124 of file item.cc.

References drizzled::Item::make_string_field(), drizzled::Item::maybe_null, and drizzled::Item::name.

Referenced by drizzled::create_tmp_field_from_item().

void drizzled::Item::top_level_item ( void  )
virtualinherited

Inform the item that there will be no distinction between its result being false or NULL.

Note

This function will be called for eg. Items that are top-level AND-parts of the WHERE clause. Items implementing this function (currently Item_cond_and and subquery-related item) enable special optimizations when they are "top level".

Reimplemented in drizzled::Item_cond_xor, drizzled::Item_cond, drizzled::Item_func_isnotnull, drizzled::Item_func_opt_neg, drizzled::Item_func_not_all, drizzled::Item_in_subselect, and drizzled::Item_bool_func2.

Definition at line 523 of file item.cc.

Referenced by drizzled::Join::exec(), drizzled::Join::optimize(), drizzled::Item_in_subselect::row_value_in_to_exists_transformer(), and drizzled::simplify_joins().

Item * drizzled::Item::transform ( Item_transformer  transformer,
unsigned char *  arg 
)
virtualinherited

Traverse item tree possibly transforming it (replacing items).

If you don't need to transform an item tree, but only traverse it, please use Item::walk() instead.

Parameters
transformerfunctor that performs transformation of a subtree
argopaque argument passed to the functor
Returns
Returns pointer to the new subtree root. Session::change_item_tree() should be called for it if transformation took place, i.e. if a pointer to newly allocated item is returned.

Reimplemented in drizzled::Item_equal, drizzled::Item_cond, drizzled::Item_in_optimizer, drizzled::Item_func, drizzled::Item_row, drizzled::Item_func_make_set, and drizzled::Item_default_value.

Definition at line 387 of file item.cc.

Referenced by drizzled::Item_default_value::transform(), drizzled::Item_func_make_set::transform(), drizzled::Item_row::transform(), drizzled::Item_func::transform(), and drizzled::Item_in_optimizer::transform().

void drizzled::Item::update_null_value ( )
virtualinherited
table_map drizzled::Item_ref::used_tables ( ) const
inlinevirtualinherited

Returns bit map of tables used by item

Reimplemented from drizzled::Item.

Reimplemented in drizzled::Item_outer_ref, and drizzled::Item_ref_null_helper.

Definition at line 89 of file ref.h.

bool drizzled::Item_ref::val_bool ( )
virtualinherited

Return boolean value of item.

Return values
falsevalue is false or NULL true value is true (not equal to 0)
Todo:
Make this functions class dependent

Reimplemented from drizzled::Item.

Reimplemented in drizzled::Item_direct_ref, and drizzled::Item_ref_null_helper.

Definition at line 488 of file ref.cc.

References drizzled::Item::fixed, and drizzled::Item::null_value.

type::Decimal * drizzled::Item_ref::val_decimal ( type::Decimal decimal_buffer)
virtualinherited

Return decimal representation of item with fixed point.

Parameters
bufferwhich can be used by Item for returning value (but can be not)
Note

Returned value should not be changed if it is not the same which was passed via argument.

Return values
Returnpointer on type::Decimal (it can be other then passed via argument) if value is not NULL (null_value flag will be reset to false). In case of NULL value it return 0 pointer and set null_value flag to true.

Implements drizzled::Item.

Reimplemented in drizzled::Item_direct_ref, and drizzled::Item_ref_null_helper.

Definition at line 519 of file ref.cc.

References drizzled::Item::null_value.

int64_t drizzled::Item_ref::val_int ( )
virtualinherited

Returns integer representation of item.

Return values
Incase of NULL value return 0 and set null_value flag to true. If value is not null null_value flag will be reset to false.

Implements drizzled::Item.

Reimplemented in drizzled::Item_direct_ref, and drizzled::Item_ref_null_helper.

Definition at line 479 of file ref.cc.

References drizzled::Item::fixed, and drizzled::Item::null_value.

int64_t drizzled::Item::val_int_endpoint ( bool  left_endp,
bool *  incl_endp 
)
virtualinherited

Converts "func_arg $CMP$ const" half-interval into "FUNC(func_arg) $CMP2$ const2"

left_endp false <=> The interval is "x < const" or "x <= const" true <=> The interval is "x > const" or "x >= const"

incl_endp IN true <=> the comparison is '<' or '>' false <=> the comparison is '<=' or '>=' OUT The same but for the "F(x) $CMP$ F(const)" comparison

This function is defined only for unary monotonic functions. The caller supplies the source half-interval

x $CMP$ const

The value of const is supplied implicitly as the value this item's argument, the form of $CMP$ comparison is specified through the function's arguments. The calle returns the result interval

F(x) $CMP2$ F(const)

passing back F(const) as the return value, and the form of $CMP2$ through the out parameter. NULL values are assumed to be comparable and be less than any non-NULL values.

Return values
Theoutput range bound, which equal to the value of val_int()
  • If the value of the function is NULL then the bound is the smallest possible value of INT64_MIN

Reimplemented in drizzled::Item_field, drizzled::Item_func_to_days, and drizzled::Item_func_year.

Definition at line 88 of file item.cc.

double drizzled::Item_ref::val_real ( )
virtualinherited

Returns double precision floating point representation of item.

Return values
Incase of NULL value return 0.0 and set null_value flag to true. If value is not null null_value flag will be reset to false.

Implements drizzled::Item.

Reimplemented in drizzled::Item_direct_ref, and drizzled::Item_ref_null_helper.

Definition at line 470 of file ref.cc.

References drizzled::Item::fixed, and drizzled::Item::null_value.

String * drizzled::Item_ref::val_str ( String str)
virtualinherited

Return string representation of this item object.

Parameters
anallocated buffer this or any nested Item object can use to store return value of this method.
Note

Buffer passed via argument should only be used if the item itself doesn't have an own String buffer. In case when the item maintains it's own string buffer, it's preferable to return it instead to minimize number of mallocs/memcpys.

The caller of this method can modify returned string, but only in case when it was allocated on heap, (is_alloced() is true). This allows the caller to efficiently use a buffer allocated by a child without having to allocate a buffer of it's own. The buffer, given to val_str() as argument, belongs to the caller and is later used by the caller at it's own choosing.

A few implications from the above:

  • unless you return a string object which only points to your buffer but doesn't manages it you should be ready that it will be modified.
  • even for not allocated strings (is_alloced() == false) the caller can change charset (see Item_func_{typecast/binary}. XXX: is this a bug?
  • still you should try to minimize data copying and return internal object whenever possible.
Return values
Incase of NULL value return 0 (NULL pointer) and set null_value flag to true. If value is not null null_value flag will be reset to false.

Implements drizzled::Item.

Reimplemented in drizzled::Item_direct_ref, and drizzled::Item_ref_null_helper.

Definition at line 497 of file ref.cc.

References drizzled::Item::fixed, and drizzled::Item::null_value.

uint64_t drizzled::Item::val_uint ( )
inlineinherited

This is just a shortcut to avoid the cast. You should still use unsigned_flag to check the sign of the item.

Definition at line 309 of file item.h.

Member Data Documentation

Item_result drizzled::Item::cmp_context
inherited
bool drizzled::Item::fixed
inherited

If item fixed with fix_fields

Definition at line 120 of file item.h.

Referenced by drizzled::add_ref_to_table_cond(), drizzled::statement::Kill::execute(), drizzled::find_order_in_list(), drizzled::Item_default_value::fix_fields(), drizzled::Item_insert_value::fix_fields(), drizzled::Item_field::fix_fields(), drizzled::Item_ref::fix_fields(), drizzled::Item_field::fix_outer_field(), drizzled::Item_func_from_days::get_temporal(), drizzled::Item_func_last_day::get_temporal(), drizzled::Item_ref::is_null(), drizzled::Item_float::Item_float(), drizzled::Item_int::Item_int(), drizzled::Join::prepare(), drizzled::Item_in_subselect::row_value_in_to_exists_transformer(), drizzled::Item_in_subselect::select_in_like_transformer(), drizzled::Item_sum_distinct::setup(), drizzled::simplify_joins(), drizzled::Item_ref_null_helper::val_bool(), drizzled::Item_ref::val_bool(), drizzled::Item_exists_subselect::val_bool(), drizzled::Item_in_subselect::val_bool(), drizzled::Item_cache_decimal::val_decimal(), drizzled::Item_cache_real::val_decimal(), drizzled::Item_cache_int::val_decimal(), drizzled::Item_cache_str::val_decimal(), drizzled::Item_real_func::val_decimal(), drizzled::Item_func_get_user_var::val_decimal(), drizzled::Item_func_min_max::val_decimal(), drizzled::Item_ref_null_helper::val_decimal(), drizzled::Item_func_numhybrid::val_decimal(), drizzled::Item_float::val_decimal(), drizzled::Item_func_set_user_var::val_decimal(), drizzled::Item_time::val_decimal(), drizzled::function::cast::Time::val_decimal(), drizzled::Item_date::val_decimal(), drizzled::Item_date_func::val_decimal(), drizzled::Item_date_typecast::val_decimal(), drizzled::Item_func::val_decimal(), drizzled::Item_datetime_typecast::val_decimal(), drizzled::Item_exists_subselect::val_decimal(), drizzled::Item_in_subselect::val_decimal(), drizzled::Item_sum_avg::val_decimal(), drizzled::Item_func_dayofyear::val_int(), drizzled::Item_func_hour::val_int(), drizzled::Item_func_microsecond::val_int(), drizzled::Item_func_minute::val_int(), drizzled::Item_func_month::val_int(), drizzled::Item_func_period_add::val_int(), drizzled::Item_func_period_diff::val_int(), drizzled::Item_func_quarter::val_int(), drizzled::Item_func_second::val_int(), drizzled::Item_func_to_days::val_int(), drizzled::Item_func_year::val_int(), drizzled::Item_func_dayofmonth::val_int(), drizzled::Item_func_from_unixtime::val_int(), drizzled::Item_func_row_count::val_int(), drizzled::Item_func_elt::val_int(), drizzled::Item_func_found_rows::val_int(), drizzled::Item_cache_decimal::val_int(), drizzled::Item_func_unix_timestamp::val_int(), drizzled::Item_func_weekday::val_int(), drizzled::Item_func_sign::val_int(), drizzled::Item_func_last_insert_id::val_int(), drizzled::Item_func_int_div::val_int(), drizzled::Item_func_ord::val_int(), drizzled::Item_cache_real::val_int(), drizzled::Item_extract::val_int(), drizzled::Item_func_field::val_int(), drizzled::Item_cache_int::val_int(), drizzled::Item_cache_str::val_int(), drizzled::Item_func_locate::val_int(), drizzled::Item_func_find_in_set::val_int(), drizzled::Item_time::val_int(), drizzled::utility_functions::BitCount::val_int(), drizzled::utility_functions::GlobalReadLock::val_int(), drizzled::function::bit::Or::val_int(), drizzled::Item_real_func::val_int(), drizzled::Item_func_makedate::val_int(), drizzled::Item_date::val_int(), drizzled::Item_func_sysdate_local::val_int(), drizzled::Item_date_add_interval::val_int(), drizzled::Item_null::val_int(), drizzled::Item_func_min_max::val_int(), drizzled::Item_func_get_user_var::val_int(), drizzled::Item_ref_null_helper::val_int(), drizzled::Item_func_now::val_int(), drizzled::function::bit::And::val_int(), drizzled::Item_float::val_int(), drizzled::Item_func_numhybrid::val_int(), drizzled::Item_func_set_user_var::val_int(), drizzled::function::bit::ShiftLeft::val_int(), drizzled::Item_int::val_int(), drizzled::function::cast::Time::val_int(), drizzled::function::bit::ShiftRight::val_int(), drizzled::Item_field::val_int(), drizzled::Item_ref::val_int(), drizzled::function::bit::Neg::val_int(), drizzled::function::bit::Xor::val_int(), drizzled::Item_string::val_int(), drizzled::Item_date_typecast::val_int(), drizzled::Item_datetime_typecast::val_int(), drizzled::Item_singlerow_subselect::val_int(), drizzled::Item_exists_subselect::val_int(), drizzled::Item_in_subselect::val_int(), drizzled::Item_sum_num::val_int(), drizzled::Item_sum_sum::val_int(), drizzled::Item_sum_count::val_int(), drizzled::Item_sum_count_distinct::val_int(), drizzled::Item_func_in::val_int(), drizzled::Item_func_isnull::val_int(), drizzled::Item_is_not_null_test::val_int(), drizzled::Item_func_isnotnull::val_int(), drizzled::Item_func_like::val_int(), drizzled::Item_cond_and::val_int(), drizzled::Item_cond_or::val_int(), drizzled::Item_cond_xor::val_int(), drizzled::Item_func_year::val_int_endpoint(), drizzled::Item_func_to_days::val_int_endpoint(), drizzled::Item_func_elt::val_real(), drizzled::Item_cache_decimal::val_real(), drizzled::Item_func_exp::val_real(), drizzled::Item_func_atan::val_real(), drizzled::Item_func_log::val_real(), drizzled::Item_func_ln::val_real(), drizzled::Item_func_units::val_real(), drizzled::Item_func_acos::val_real(), drizzled::Item_func_asin::val_real(), drizzled::Item_func_cos::val_real(), drizzled::Item_func_pow::val_real(), drizzled::Item_func_sqrt::val_real(), drizzled::Item_func_sin::val_real(), drizzled::Item_func_tan::val_real(), drizzled::Item_cache_real::val_real(), drizzled::Item_uint::val_real(), drizzled::Item_hex_string::val_real(), drizzled::Item_func_month::val_real(), drizzled::Item_func_weekday::val_real(), drizzled::Item_cache_str::val_real(), drizzled::Item_cache_int::val_real(), drizzled::Item_func_sysdate_local::val_real(), drizzled::Item_int_func::val_real(), drizzled::Item_func_log2::val_real(), drizzled::Item_null::val_real(), drizzled::Item_func_min_max::val_real(), drizzled::Item_ref_null_helper::val_real(), drizzled::Item_func_get_user_var::val_real(), drizzled::Item_float::val_real(), drizzled::Item_func_numhybrid::val_real(), drizzled::Item_func_set_user_var::val_real(), drizzled::Item_func_log10::val_real(), drizzled::Item_int::val_real(), drizzled::Item_ref::val_real(), drizzled::Item_field::val_real(), drizzled::Item_string::val_real(), drizzled::Item_singlerow_subselect::val_real(), drizzled::Item_exists_subselect::val_real(), drizzled::Item_in_subselect::val_real(), drizzled::Item_sum_int::val_real(), drizzled::Item_sum_sum::val_real(), drizzled::Item_sum_avg::val_real(), drizzled::Item_sum_std::val_real(), drizzled::Item_func_collation::val_str(), drizzled::Item_func_set_collation::val_str(), drizzled::Item_func_makedate::val_str(), drizzled::Item_func_conv::val_str(), drizzled::Item_func_right::val_str(), drizzled::Item_func_binary::val_str(), drizzled::Item_func_left::val_str(), drizzled::Item_func_dayname::val_str(), drizzled::Item_func_elt::val_str(), drizzled::Item_func_quote::val_str(), drizzled::Item_func_from_unixtime::val_str(), drizzled::Item_cache_decimal::val_str(), drizzled::Item_func_char::val_str(), drizzled::Item_uint::val_str(), drizzled::utility_functions::Schema::val_str(), drizzled::Item_cache_real::val_str(), drizzled::Item_str_conv::val_str(), drizzled::Item_func_trim::val_str(), drizzled::Item_typecast::val_str(), drizzled::utility_functions::Catalog::val_str(), drizzled::Item_func_rpad::val_str(), drizzled::Item_time::val_str(), drizzled::Item_func_weekday::val_str(), drizzled::Item_cache_int::val_str(), drizzled::Item_cache_str::val_str(), drizzled::utility_functions::GlobalReadLock::val_str(), drizzled::utility_functions::ResultType::val_str(), drizzled::Item_real_func::val_str(), drizzled::Item_date_add_interval::val_str(), drizzled::utility_functions::User::val_str(), drizzled::Item_func_repeat::val_str(), drizzled::Item_hex_string::val_str(), drizzled::Item_date::val_str(), drizzled::Item_func_make_set::val_str(), drizzled::Item_func_replace::val_str(), drizzled::utility_functions::Typeof::val_str(), drizzled::Item_func_insert::val_str(), drizzled::function::cast::Time::val_str(), drizzled::Item_int_func::val_str(), drizzled::Item_func_sysdate_local::val_str(), drizzled::Item_null::val_str(), drizzled::Item_func_min_max::val_str(), drizzled::Item_ref_null_helper::val_str(), drizzled::Item_func_get_user_var::val_str(), drizzled::Item_func_now::val_str(), drizzled::Item_func_ltrim::val_str(), drizzled::Item_float::val_str(), drizzled::Item_func_numhybrid::val_str(), drizzled::Item_func_set_user_var::val_str(), drizzled::Item_func_lpad::val_str(), drizzled::Item_func_monthname::val_str(), drizzled::Item_func_rtrim::val_str(), drizzled::Item_int::val_str(), drizzled::Item_func_conv_charset::val_str(), drizzled::Item_field::val_str(), drizzled::Item_ref::val_str(), drizzled::Item_char_typecast::val_str(), drizzled::Item_string::val_str(), drizzled::Item_date_typecast::val_str(), drizzled::Item_datetime_typecast::val_str(), drizzled::Item_exists_subselect::val_str(), drizzled::Item_in_subselect::val_str(), and drizzled::Item_func_group_concat::val_str().

bool drizzled::Item::is_autogenerated_name
inherited

indicates whether name of this Item was autogenerated or set by user

Definition at line 136 of file item.h.

Referenced by drizzled::Create_func_arg1::create(), drizzled::Create_func_arg2::create(), and drizzled::Create_func_arg3::create().

uint32_t drizzled::Item::name_length
inherited

Length of name

Definition at line 113 of file item.h.

bool drizzled::Item::null_value
inherited

True if item is null

Definition at line 122 of file item.h.

Referenced by drizzled::Item_func_abs::decimal_op(), drizzled::Item_func_plus::decimal_op(), drizzled::Item_func_floor::decimal_op(), drizzled::Item_func_ceiling::decimal_op(), drizzled::Item_func_minus::decimal_op(), drizzled::Item_func_neg::decimal_op(), drizzled::field_is_equal_to_item(), drizzled::Item_func_from_unixtime::get_date(), drizzled::Item_date_add_interval::get_date(), drizzled::Item_ref_null_helper::get_date(), drizzled::Item_direct_ref::get_date(), drizzled::Item_ref::get_date(), drizzled::Item_field::get_date(), drizzled::Item_func_from_days::get_temporal(), drizzled::Item_func_last_day::get_temporal(), drizzled::Item_field::get_time(), drizzled::Item_date_typecast::get_time(), drizzled::TemporalInterval::initFromItem(), drizzled::Item_func_abs::int_op(), drizzled::Item_func_ceiling::int_op(), drizzled::Item_func_floor::int_op(), drizzled::Item_func_plus::int_op(), drizzled::Item_func_minus::int_op(), drizzled::Item_func_neg::int_op(), drizzled::Item_row::is_null(), drizzled::Item_copy_string::is_null(), drizzled::Item_func_numhybrid::is_null(), drizzled::Item_subselect::is_null(), drizzled::Item_func::is_null(), drizzled::Item_sum::is_null(), drizzled::Item_avg_field::is_null(), drizzled::Item_variance_field::is_null(), drizzled::SortParam::make_sortkey(), drizzled::Item_func_abs::real_op(), drizzled::Item_func_plus::real_op(), drizzled::Item_func_ceiling::real_op(), drizzled::Item_func_floor::real_op(), drizzled::Item_func_minus::real_op(), drizzled::Item_func_neg::real_op(), drizzled::Item_field::save_org_in_field(), drizzled::Item::send(), drizzled::Item_sum_distinct::setup(), drizzled::string_functions::Regex::val_bool(), drizzled::Item_direct_ref::val_bool(), drizzled::Item_ref_null_helper::val_bool(), drizzled::utility_functions::Execute::val_bool(), drizzled::Item_ref::val_bool(), drizzled::Item_singlerow_subselect::val_bool(), drizzled::Item_in_subselect::val_bool(), drizzled::Item_real_func::val_decimal(), drizzled::Item_decimal_typecast::val_decimal(), drizzled::Item_func_min_max::val_decimal(), drizzled::Item_func_get_user_var::val_decimal(), drizzled::Item_direct_ref::val_decimal(), drizzled::Item_ref_null_helper::val_decimal(), drizzled::Item_func_set_user_var::val_decimal(), drizzled::Item_copy_string::val_decimal(), drizzled::Item_ref::val_decimal(), drizzled::Item_field::val_decimal(), drizzled::Item_singlerow_subselect::val_decimal(), drizzled::Item_in_subselect::val_decimal(), drizzled::Item_sum_distinct::val_decimal(), drizzled::Item_sum_avg::val_decimal(), drizzled::Item_func_if::val_decimal(), drizzled::Item_func_case::val_decimal(), drizzled::Item_func_dayofyear::val_int(), drizzled::Item_func_hour::val_int(), drizzled::Item_func_microsecond::val_int(), drizzled::Item_func_minute::val_int(), drizzled::Item_func_month::val_int(), drizzled::Item_func_period_add::val_int(), drizzled::Item_func_period_diff::val_int(), drizzled::Item_func_quarter::val_int(), drizzled::Item_func_second::val_int(), drizzled::Item_func_to_days::val_int(), drizzled::Item_func_year::val_int(), drizzled::Item_func_dayofmonth::val_int(), drizzled::Item_func_elt::val_int(), drizzled::Item_func_last_insert_id::val_int(), drizzled::Item_func_int_div::val_int(), drizzled::Item_func_ord::val_int(), drizzled::Item_func_unix_timestamp::val_int(), drizzled::Item_func_weekday::val_int(), drizzled::Item_func_sign::val_int(), drizzled::Item_func_timestamp_diff::val_int(), user_locks::GetLock::val_int(), user_locks::GetLocks::val_int(), user_locks::IsFreeLock::val_int(), user_locks::IsUsedLock::val_int(), user_locks::ReleaseLock::val_int(), drizzled::Item_func_field::val_int(), user_locks::barriers::Wait::val_int(), drizzled::Item_extract::val_int(), user_locks::barriers::Release::val_int(), user_locks::barriers::WaitUntil::val_int(), user_locks::barriers::CreateBarrier::val_int(), user_locks::locks::ReleaseAndWait::val_int(), user_locks::barriers::Signal::val_int(), user_locks::locks::WaitFor::val_int(), drizzled::Item_func_locate::val_int(), plugin::catalog::functions::Create::val_int(), plugin::catalog::functions::Lock::val_int(), plugin::catalog::functions::Drop::val_int(), plugin::catalog::functions::Unlock::val_int(), drizzled::Item_func_find_in_set::val_int(), drizzled::function::cast::Unsigned::val_int(), drizzled::utility_functions::BitCount::val_int(), drizzled::function::bit::Or::val_int(), drizzled::function::cast::Signed::val_int(), drizzled::utility_functions::GlobalReadLock::val_int(), drizzled::Item_decimal_typecast::val_int(), drizzled::Item_func_makedate::val_int(), drizzled::Item_null::val_int(), drizzled::Item_func_min_max::val_int(), drizzled::Item_func_get_user_var::val_int(), drizzled::Item_direct_ref::val_int(), drizzled::Item_ref_null_helper::val_int(), drizzled::function::bit::And::val_int(), drizzled::Item_func_set_user_var::val_int(), drizzled::Item_copy_string::val_int(), drizzled::function::bit::ShiftLeft::val_int(), drizzled::function::bit::ShiftRight::val_int(), drizzled::Item_ref::val_int(), drizzled::Item_field::val_int(), drizzled::function::bit::Neg::val_int(), drizzled::function::bit::Xor::val_int(), drizzled::Item_date_typecast::val_int(), drizzled::Item_datetime_typecast::val_int(), drizzled::Item_singlerow_subselect::val_int(), drizzled::Item_in_subselect::val_int(), drizzled::Item_func_interval::val_int(), drizzled::Item_func_if::val_int(), drizzled::Item_func_case::val_int(), drizzled::Item_func_in::val_int(), drizzled::Item_func_like::val_int(), drizzled::Item_equal::val_int(), drizzled::Item_cond_and::val_int(), drizzled::Item_cond_or::val_int(), drizzled::Item_cond_xor::val_int(), drizzled::Item_func_to_days::val_int_endpoint(), drizzled::Item_field::val_int_endpoint(), drizzled::Item_func_elt::val_real(), drizzled::Item_func_units::val_real(), drizzled::Item_func_sqrt::val_real(), drizzled::Item_func_atan::val_real(), drizzled::Item_func_exp::val_real(), drizzled::Item_func_tan::val_real(), drizzled::Item_func_pow::val_real(), drizzled::Item_func_log::val_real(), drizzled::Item_func_acos::val_real(), drizzled::Item_func_sin::val_real(), drizzled::Item_func_ln::val_real(), drizzled::Item_func_cos::val_real(), drizzled::Item_func_asin::val_real(), drizzled::Item_decimal_typecast::val_real(), drizzled::Item_null::val_real(), drizzled::Item_func_log2::val_real(), drizzled::Item_func_min_max::val_real(), drizzled::Item_ref_null_helper::val_real(), drizzled::Item_func_get_user_var::val_real(), drizzled::Item_direct_ref::val_real(), drizzled::Item_copy_string::val_real(), drizzled::Item_func_set_user_var::val_real(), drizzled::Item_func_log10::val_real(), drizzled::Item_ref::val_real(), drizzled::Item_field::val_real(), drizzled::Item_singlerow_subselect::val_real(), drizzled::Item_in_subselect::val_real(), drizzled::Item_sum_avg::val_real(), drizzled::Item_func_if::val_real(), drizzled::Item_variance_field::val_real(), drizzled::Item_func_case::val_real(), drizzled::Item_func_set_collation::val_str(), drizzled::Item_func_makedate::val_str(), drizzled::Item_func_collation::val_str(), drizzled::Item_func_left::val_str(), drizzled::Item_func_right::val_str(), drizzled::Item_func_binary::val_str(), drizzled::Item_func_dayname::val_str(), drizzled::Item_func_conv::val_str(), drizzled::Item_func_elt::val_str(), drizzled::Item_func_quote::val_str(), drizzled::Item_func_char::val_str(), drizzled::utility_functions::Schema::val_str(), drizzled::Item_func_trim::val_str(), drizzled::Item_func_month::val_str(), drizzled::Item_str_conv::val_str(), drizzled::Item_typecast::val_str(), drizzled::Item_func_weekday::val_str(), drizzled::Item_func_rpad::val_str(), drizzled::Item_real_func::val_str(), drizzled::utility_functions::User::val_str(), drizzled::utility_functions::ResultType::val_str(), drizzled::Item_decimal_typecast::val_str(), drizzled::utility_functions::GlobalReadLock::val_str(), drizzled::function::cast::Boolean::val_str(), drizzled::Item_func_repeat::val_str(), drizzled::Item_func_replace::val_str(), drizzled::Item_func_make_set::val_str(), drizzled::utility_functions::Typeof::val_str(), drizzled::Item_func_insert::val_str(), drizzled::Item_int_func::val_str(), drizzled::function::cast::Time::val_str(), drizzled::Item_null::val_str(), drizzled::Item_func_min_max::val_str(), drizzled::Item_ref_null_helper::val_str(), drizzled::Item_direct_ref::val_str(), drizzled::Item_func_get_user_var::val_str(), drizzled::Item_func_ltrim::val_str(), drizzled::Item_func_numhybrid::val_str(), drizzled::Item_func_set_user_var::val_str(), drizzled::Item_func_lpad::val_str(), drizzled::Item_func_monthname::val_str(), drizzled::Item_func_rtrim::val_str(), drizzled::Item_copy_string::val_str(), drizzled::Item_func_conv_charset::val_str(), drizzled::Item_field::val_str(), drizzled::Item_ref::val_str(), drizzled::Item_char_typecast::val_str(), drizzled::Item_date_typecast::val_str(), drizzled::Item_datetime_typecast::val_str(), drizzled::Item_singlerow_subselect::val_str(), drizzled::Item_in_subselect::val_str(), drizzled::Item_sum_distinct::val_str(), drizzled::Item_func_if::val_str(), and drizzled::Item_func_group_concat::val_str().

String drizzled::Item::str_value
inherited
bool drizzled::Item::with_subselect
inherited

If this item is a subselect or some of its arguments is or contains a subselect. Computed by fix_fields.

Definition at line 142 of file item.h.

Referenced by drizzled::remove_constants(), drizzled::Item_is_not_null_test::update_used_tables(), drizzled::Item_func_isnull::val_int(), and drizzled::Item_is_not_null_test::val_int().


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