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/*
Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#include "my_global.h" /* NO_EMBEDDED_ACCESS_CHECKS */
#include "sql_priv.h"
#include "unireg.h" // REQUIRED: for other includes
#include <mysql.h>
#include <m_ctype.h>
#include "my_dir.h"
#include "sp_rcontext.h"
#include "sp_head.h" // sp_prepare_func_item
#include "sp.h" // sp_map_item_type
#include "sql_trigger.h"
#include "sql_select.h"
#include "sql_show.h" // append_identifier
#include "sql_view.h" // VIEW_ANY_SQL
#include "sql_time.h" // str_to_datetime_with_warn,
// make_truncated_value_warning
#include "sql_acl.h" // get_column_grant,
// SELECT_ACL, UPDATE_ACL,
// INSERT_ACL,
// check_grant_column
#include "sql_base.h" // enum_resolution_type,
// REPORT_EXCEPT_NOT_FOUND,
// find_item_in_list,
// RESOLVED_AGAINST_ALIAS, ...
#include "log_event.h" // append_query_string
#include "sql_test.h" // print_where
#include "sql_optimizer.h" // JOIN
using std::min;
using std::max;
const String my_null_string("NULL", 4, default_charset_info);
/****************************************************************************/
/* Hybrid_type_traits {_real} */
void Hybrid_type_traits::fix_length_and_dec(Item *item, Item *arg) const
{
item->decimals= NOT_FIXED_DEC;
item->max_length= item->float_length(arg->decimals);
}
static const Hybrid_type_traits real_traits_instance;
const Hybrid_type_traits *Hybrid_type_traits::instance()
{
return &real_traits_instance;
}
my_decimal *
Hybrid_type_traits::val_decimal(Hybrid_type *val, my_decimal *to) const
{
double2my_decimal(E_DEC_FATAL_ERROR, val->real, val->dec_buf);
return val->dec_buf;
}
String *
Hybrid_type_traits::val_str(Hybrid_type *val, String *to, uint8 decimals) const
{
to->set_real(val->real, decimals, &my_charset_bin);
return to;
}
/* Hybrid_type_traits_decimal */
static const Hybrid_type_traits_decimal decimal_traits_instance;
const Hybrid_type_traits_decimal *Hybrid_type_traits_decimal::instance()
{
return &decimal_traits_instance;
}
void
Hybrid_type_traits_decimal::fix_length_and_dec(Item *item, Item *arg) const
{
item->decimals= arg->decimals;
item->max_length= min<uint32>(arg->max_length + DECIMAL_LONGLONG_DIGITS,
DECIMAL_MAX_STR_LENGTH);
}
void Hybrid_type_traits_decimal::set_zero(Hybrid_type *val) const
{
my_decimal_set_zero(&val->dec_buf[0]);
val->used_dec_buf_no= 0;
}
void Hybrid_type_traits_decimal::add(Hybrid_type *val, Field *f) const
{
my_decimal_add(E_DEC_FATAL_ERROR,
&val->dec_buf[val->used_dec_buf_no ^ 1],
&val->dec_buf[val->used_dec_buf_no],
f->val_decimal(&val->dec_buf[2]));
val->used_dec_buf_no^= 1;
}
/**
@todo
what is '4' for scale?
*/
void Hybrid_type_traits_decimal::div(Hybrid_type *val, ulonglong u) const
{
int2my_decimal(E_DEC_FATAL_ERROR, u, TRUE, &val->dec_buf[2]);
/* XXX: what is '4' for scale? */
my_decimal_div(E_DEC_FATAL_ERROR,
&val->dec_buf[val->used_dec_buf_no ^ 1],
&val->dec_buf[val->used_dec_buf_no],
&val->dec_buf[2], 4);
val->used_dec_buf_no^= 1;
}
longlong
Hybrid_type_traits_decimal::val_int(Hybrid_type *val, bool unsigned_flag) const
{
longlong result;
my_decimal2int(E_DEC_FATAL_ERROR, &val->dec_buf[val->used_dec_buf_no],
unsigned_flag, &result);
return result;
}
double
Hybrid_type_traits_decimal::val_real(Hybrid_type *val) const
{
my_decimal2double(E_DEC_FATAL_ERROR, &val->dec_buf[val->used_dec_buf_no],
&val->real);
return val->real;
}
String *
Hybrid_type_traits_decimal::val_str(Hybrid_type *val, String *to,
uint8 decimals) const
{
my_decimal_round(E_DEC_FATAL_ERROR, &val->dec_buf[val->used_dec_buf_no],
decimals, FALSE, &val->dec_buf[2]);
my_decimal2string(E_DEC_FATAL_ERROR, &val->dec_buf[2], 0, 0, 0, to);
return to;
}
/* Hybrid_type_traits_integer */
static const Hybrid_type_traits_integer integer_traits_instance;
const Hybrid_type_traits_integer *Hybrid_type_traits_integer::instance()
{
return &integer_traits_instance;
}
void
Hybrid_type_traits_integer::fix_length_and_dec(Item *item, Item *arg) const
{
item->decimals= 0;
item->max_length= MY_INT64_NUM_DECIMAL_DIGITS;
item->unsigned_flag= 0;
}
/*****************************************************************************
** Item functions
*****************************************************************************/
/**
Init all special items.
*/
void item_init(void)
{
item_user_lock_init();
uuid_short_init();
}
/**
@todo
Make this functions class dependent
*/
bool Item::val_bool()
{
switch(result_type()) {
case INT_RESULT:
return val_int() != 0;
case DECIMAL_RESULT:
{
my_decimal decimal_value;
my_decimal *val= val_decimal(&decimal_value);
if (val)
return !my_decimal_is_zero(val);
return 0;
}
case REAL_RESULT:
case STRING_RESULT:
return val_real() != 0.0;
case ROW_RESULT:
default:
DBUG_ASSERT(0);
return 0; // Wrong (but safe)
}
}
/*
For the items which don't have its own fast val_str_ascii()
implementation we provide a generic slower version,
which converts from the Item character set to ASCII.
For better performance conversion happens only in
case of a "tricky" Item character set (e.g. UCS2).
Normally conversion does not happen.
*/
String *Item::val_str_ascii(String *str)
{
DBUG_ASSERT(str != &str_value);
uint errors;
String *res= val_str(&str_value);
if (!res)
return 0;
if (!(res->charset()->state & MY_CS_NONASCII))
str= res;
else
{
if ((null_value= str->copy(res->ptr(), res->length(), collation.collation,
&my_charset_latin1, &errors)))
return 0;
}
return str;
}
String *Item::val_string_from_real(String *str)
{
double nr= val_real();
if (null_value)
return 0; /* purecov: inspected */
str->set_real(nr,decimals, &my_charset_bin);
return str;
}
String *Item::val_string_from_int(String *str)
{
longlong nr= val_int();
if (null_value)
return 0;
str->set_int(nr, unsigned_flag, &my_charset_bin);
return str;
}
String *Item::val_string_from_decimal(String *str)
{
my_decimal dec_buf, *dec= val_decimal(&dec_buf);
if (null_value)
return 0;
my_decimal_round(E_DEC_FATAL_ERROR, dec, decimals, FALSE, &dec_buf);
my_decimal2string(E_DEC_FATAL_ERROR, &dec_buf, 0, 0, 0, str);
return str;
}
String *Item::val_string_from_datetime(String *str)
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
if (get_date(<ime, TIME_FUZZY_DATE) ||
(null_value= str->alloc(MAX_DATE_STRING_REP_LENGTH)))
return (String *) 0;
make_datetime((DATE_TIME_FORMAT *) 0, <ime, str, decimals);
return str;
}
String *Item::val_string_from_date(String *str)
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
if (get_date(<ime, TIME_FUZZY_DATE) ||
(null_value= str->alloc(MAX_DATE_STRING_REP_LENGTH)))
return (String *) 0;
make_date((DATE_TIME_FORMAT *) 0, <ime, str);
return str;
}
String *Item::val_string_from_time(String *str)
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
if (get_time(<ime) || (null_value= str->alloc(MAX_DATE_STRING_REP_LENGTH)))
return (String *) 0;
make_time((DATE_TIME_FORMAT *) 0, <ime, str, decimals);
return str;
}
my_decimal *Item::val_decimal_from_real(my_decimal *decimal_value)
{
double nr= val_real();
if (null_value)
return 0;
double2my_decimal(E_DEC_FATAL_ERROR, nr, decimal_value);
return (decimal_value);
}
my_decimal *Item::val_decimal_from_int(my_decimal *decimal_value)
{
longlong nr= val_int();
if (null_value)
return 0;
int2my_decimal(E_DEC_FATAL_ERROR, nr, unsigned_flag, decimal_value);
return decimal_value;
}
my_decimal *Item::val_decimal_from_string(my_decimal *decimal_value)
{
String *res;
if (!(res= val_str(&str_value)))
return NULL;
if (str2my_decimal(E_DEC_FATAL_ERROR & ~E_DEC_BAD_NUM,
res->ptr(), res->length(), res->charset(),
decimal_value) & E_DEC_BAD_NUM)
{
ErrConvString err(res);
push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
ER_TRUNCATED_WRONG_VALUE,
ER(ER_TRUNCATED_WRONG_VALUE), "DECIMAL",
err.ptr());
}
return decimal_value;
}
my_decimal *Item::val_decimal_from_date(my_decimal *decimal_value)
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
if (get_date(<ime, TIME_FUZZY_DATE))
{
/*
The conversion may fail in strict mode. Do not return a NULL pointer,
as the result may be used in subsequent arithmetic operations.
*/
my_decimal_set_zero(decimal_value);
null_value= 1; // set NULL, stop processing
return decimal_value;;
}
return date2my_decimal(<ime, decimal_value);
}
my_decimal *Item::val_decimal_from_time(my_decimal *decimal_value)
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
if (get_time(<ime))
{
my_decimal_set_zero(decimal_value);
null_value= 1;
return 0;
}
return date2my_decimal(<ime, decimal_value);
}
longlong Item::val_time_temporal()
{
MYSQL_TIME ltime;
if ((null_value= get_time(<ime)))
return 0;
return TIME_to_longlong_time_packed(<ime);
}
longlong Item::val_date_temporal()
{
MYSQL_TIME ltime;
longlong flags= (TIME_FUZZY_DATE | MODE_INVALID_DATES |
(current_thd->variables.sql_mode &
(MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE)));
if ((null_value= get_date(<ime, flags)))
return 0;
return TIME_to_longlong_datetime_packed(<ime);
}
// TS-TODO: split into separate methods?
longlong Item::val_temporal_with_round(enum_field_types type, uint8 dec)
{
longlong nr= val_temporal_by_field_type();
longlong diff= my_time_fraction_remainder(MY_PACKED_TIME_GET_FRAC_PART(nr),
dec);
longlong abs_diff= diff > 0 ? diff : - diff;
if (abs_diff * 2 >= (int) log_10_int[DATETIME_MAX_DECIMALS - dec])
{
/* Needs rounding */
switch (type)
{
case MYSQL_TYPE_TIME:
{
MYSQL_TIME ltime;
TIME_from_longlong_time_packed(<ime, nr);
return my_time_round(<ime, dec) ?
0 : TIME_to_longlong_time_packed(<ime);
}
case MYSQL_TYPE_TIMESTAMP:
case MYSQL_TYPE_DATETIME:
{
MYSQL_TIME ltime;
int warnings= 0;
TIME_from_longlong_datetime_packed(<ime, nr);
return my_datetime_round(<ime, dec, &warnings) ?
0 : TIME_to_longlong_datetime_packed(<ime);
return nr;
}
default:
DBUG_ASSERT(0);
break;
}
}
/* Does not need rounding, do simple truncation. */
nr-= diff;
return nr;
}
double Item::val_real_from_decimal()
{
/* Note that fix_fields may not be called for Item_avg_field items */
double result;
my_decimal value_buff, *dec_val= val_decimal(&value_buff);
if (null_value)
return 0.0;
my_decimal2double(E_DEC_FATAL_ERROR, dec_val, &result);
return result;
}
longlong Item::val_int_from_decimal()
{
/* Note that fix_fields may not be called for Item_avg_field items */
longlong result;
my_decimal value, *dec_val= val_decimal(&value);
if (null_value)
return 0;
my_decimal2int(E_DEC_FATAL_ERROR, dec_val, unsigned_flag, &result);
return result;
}
longlong Item::val_int_from_time()
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
return get_time(<ime) ?
0LL : (ltime.neg ? -1 : 1) * TIME_to_ulonglong_time_round(<ime);
}
longlong Item::val_int_from_date()
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
return get_date(<ime, TIME_FUZZY_DATE) ?
0LL : (longlong) TIME_to_ulonglong_date(<ime);
}
longlong Item::val_int_from_datetime()
{
DBUG_ASSERT(fixed == 1);
MYSQL_TIME ltime;
return get_date(<ime, TIME_FUZZY_DATE) ?
0LL: (longlong) TIME_to_ulonglong_datetime_round(<ime);
}
type_conversion_status Item::save_time_in_field(Field *field)
{
MYSQL_TIME ltime;
if (get_time(<ime))
return set_field_to_null_with_conversions(field, 0);
field->set_notnull();
return field->store_time(<ime, decimals);
}
type_conversion_status Item::save_date_in_field(Field *field)
{
MYSQL_TIME ltime;
if (get_date(<ime, TIME_FUZZY_DATE))
return set_field_to_null_with_conversions(field, 0);
field->set_notnull();
return field->store_time(<ime, decimals);
}
/*
Store the string value in field directly
SYNOPSIS
Item::save_str_value_in_field()
field a pointer to field where to store
result the pointer to the string value to be stored
DESCRIPTION
The method is used by Item_*::save_in_field implementations
when we don't need to calculate the value to store
See Item_string::save_in_field() implementation for example
IMPLEMENTATION
Check if the Item is null and stores the NULL or the
result value in the field accordingly.
RETURN
Nonzero value if error
*/
type_conversion_status
Item::save_str_value_in_field(Field *field, String *result)
{
if (null_value)
return set_field_to_null(field);
field->set_notnull();
return field->store(result->ptr(), result->length(), collation.collation);
}
Item::Item():
is_expensive_cache(-1), rsize(0),
marker(0), fixed(0),
collation(&my_charset_bin, DERIVATION_COERCIBLE),
runtime_item(false), with_subselect(false),
with_stored_program(false), tables_locked_cache(false)
{
maybe_null=null_value=with_sum_func=unsigned_flag=0;
decimals= 0; max_length= 0;
cmp_context= (Item_result)-1;
/* Put item in free list so that we can free all items at end */
THD *thd= current_thd;
next= thd->free_list;
thd->free_list= this;
/*
Item constructor can be called during execution other then SQL_COM
command => we should check thd->lex->current_select on zero (thd->lex
can be uninitialised)
*/
if (thd->lex->current_select)
{
enum_parsing_place place=
thd->lex->current_select->parsing_place;
if (place == SELECT_LIST ||
place == IN_HAVING)
thd->lex->current_select->select_n_having_items++;
}
}
/**
Constructor used by Item_field, Item_ref & aggregate (sum)
functions.
Used for duplicating lists in processing queries with temporary
tables.
*/
Item::Item(THD *thd, Item *item):
is_expensive_cache(-1),
rsize(0),
str_value(item->str_value),
item_name(item->item_name),
orig_name(item->orig_name),
max_length(item->max_length),
marker(item->marker),
decimals(item->decimals),
maybe_null(item->maybe_null),
null_value(item->null_value),
unsigned_flag(item->unsigned_flag),
with_sum_func(item->with_sum_func),
fixed(item->fixed),
collation(item->collation),
cmp_context(item->cmp_context),
runtime_item(false),
with_subselect(item->has_subquery()),
with_stored_program(item->with_stored_program),
tables_locked_cache(item->tables_locked_cache)
{
next= thd->free_list; // Put in free list
thd->free_list= this;
}
uint Item::decimal_precision() const
{
Item_result restype= result_type();
if ((restype == DECIMAL_RESULT) || (restype == INT_RESULT))
{
uint prec=
my_decimal_length_to_precision(max_char_length(), decimals,
unsigned_flag);
return min<uint>(prec, DECIMAL_MAX_PRECISION);
}
switch (field_type())
{
case MYSQL_TYPE_TIME:
return decimals + TIME_INT_DIGITS;
case MYSQL_TYPE_DATETIME:
case MYSQL_TYPE_TIMESTAMP:
return decimals + DATETIME_INT_DIGITS;
case MYSQL_TYPE_DATE:
return decimals + DATE_INT_DIGITS;
default:
break;
}
return min<uint>(max_char_length(), DECIMAL_MAX_PRECISION);
}
uint Item::time_precision()
{
if (const_item() && result_type() == STRING_RESULT && !is_temporal())
{
MYSQL_TIME ltime;
String buf, *tmp;
MYSQL_TIME_STATUS status;
DBUG_ASSERT(fixed);
// Nanosecond rounding is not needed, for performance purposes
if ((tmp= val_str(&buf)) &&
str_to_time(tmp, <ime, TIME_NO_NSEC_ROUNDING, &status) == 0)
return MY_MIN(status.fractional_digits, DATETIME_MAX_DECIMALS);
}
return MY_MIN(decimals, DATETIME_MAX_DECIMALS);
}
uint Item::datetime_precision()
{
if (const_item() && result_type() == STRING_RESULT && !is_temporal())
{
MYSQL_TIME ltime;
String buf, *tmp;
MYSQL_TIME_STATUS status;
DBUG_ASSERT(fixed);
// Nanosecond rounding is not needed, for performance purposes
if ((tmp= val_str(&buf)) &&
!str_to_datetime(tmp, <ime, TIME_NO_NSEC_ROUNDING | TIME_FUZZY_DATE,
&status))
return MY_MIN(status.fractional_digits, DATETIME_MAX_DECIMALS);
}
return MY_MIN(decimals, DATETIME_MAX_DECIMALS);
}
void Item::print_item_w_name(String *str, enum_query_type query_type)
{
print(str, query_type);
if (item_name.is_set())
{
THD *thd= current_thd;
str->append(STRING_WITH_LEN(" AS "));
append_identifier(thd, str, item_name);
}
}
/**
@details
"SELECT (subq) GROUP BY (same_subq)" confuses ONLY_FULL_GROUP_BY (it does
not see that both subqueries are the same, raises an error).
To avoid hitting this problem, if the original query was:
"SELECT expression AS x GROUP BY x", we print "GROUP BY x", not
"GROUP BY expression". Same for ORDER BY.
This has practical importance for views created as
"CREATE VIEW v SELECT (subq) AS x GROUP BY x"
(print_order() is used to write the view's definition in the frm file).
We make one exception: if the view is merge-able, its ORDER clause will be
merged into the parent query's. If an identifier in the merged ORDER clause
is allowed to be either an alias or an expression of the view's underlying
tables, resolution is difficult: it may be to be found in the underlying
tables of the view, or in the SELECT list of the view; unlike other ORDER
elements directly originating from the parent query.
To avoid this problem, if the view is merge-able, we print the
expression. This does not cause problems with only_full_group_by, because a
merge-able view never has GROUP BY. @see mysql_register_view().
*/
void Item::print_for_order(String *str,
enum_query_type query_type,
bool used_alias)
{
if (used_alias)
{
DBUG_ASSERT(item_name.is_set());
// In the clause, user has referenced expression using an alias; we use it
append_identifier(current_thd, str, item_name);
}
else
print(str,query_type);
}
void Item::cleanup()
{
DBUG_ENTER("Item::cleanup");
fixed=0;
marker= 0;
tables_locked_cache= false;
if (orig_name.is_set())
item_name= orig_name;
DBUG_VOID_RETURN;
}
/**
cleanup() item if it is 'fixed'.
@param arg a dummy parameter, is not used here
*/
bool Item::cleanup_processor(uchar *arg)
{
if (fixed)
cleanup();
return FALSE;
}
/**
rename item (used for views, cleanup() return original name).
@param new_name new name of item;
*/
void Item::rename(char *new_name)
{
/*
we can compare pointers to names here, because if name was not changed,
pointer will be same
*/
if (!orig_name.is_set() && new_name != item_name.ptr())
orig_name= item_name;
item_name.set(new_name);
}
/**
Traverse item tree possibly transforming it (replacing items).
This function is designed to ease transformation of Item trees.
Re-execution note: every such transformation is registered for
rollback by THD::change_item_tree() and is rolled back at the end
of execution by THD::rollback_item_tree_changes().
Therefore:
- this function can not be used at prepared statement prepare
(in particular, in fix_fields!), as only permanent
transformation of Item trees are allowed at prepare.
- the transformer function shall allocate new Items in execution
memory root (thd->mem_root) and not anywhere else: allocated
items will be gone in the end of execution.
If you don't need to transform an item tree, but only traverse
it, please use Item::walk() instead.
@param transformer functor that performs transformation of a subtree
@param arg opaque argument passed to the functor
@return
Returns pointer to the new subtree root. THD::change_item_tree()
should be called for it if transformation took place, i.e. if a
pointer to newly allocated item is returned.
*/
Item* Item::transform(Item_transformer transformer, uchar *arg)
{
DBUG_ASSERT(!current_thd->stmt_arena->is_stmt_prepare());
return (this->*transformer)(arg);
}
Item_ident::Item_ident(Name_resolution_context *context_arg,
const char *db_name_arg,const char *table_name_arg,
const char *field_name_arg)
:orig_db_name(db_name_arg), orig_table_name(table_name_arg),
orig_field_name(field_name_arg), context(context_arg),
db_name(db_name_arg), table_name(table_name_arg),
field_name(field_name_arg),
alias_name_used(FALSE), cached_field_index(NO_CACHED_FIELD_INDEX),
cached_table(0), depended_from(0)
{
item_name.set(field_name_arg);
}
/**
Constructor used by Item_field & Item_*_ref (see Item comment)
*/
Item_ident::Item_ident(THD *thd, Item_ident *item)
:Item(thd, item),
orig_db_name(item->orig_db_name),
orig_table_name(item->orig_table_name),
orig_field_name(item->orig_field_name),
context(item->context),
db_name(item->db_name),
table_name(item->table_name),
field_name(item->field_name),
alias_name_used(item->alias_name_used),
cached_field_index(item->cached_field_index),
cached_table(item->cached_table),
depended_from(item->depended_from)
{}
void Item_ident::cleanup()
{
DBUG_ENTER("Item_ident::cleanup");
#ifdef CANT_BE_USED_AS_MEMORY_IS_FREED
db_name ? db_name : "(null)",
orig_db_name ? orig_db_name : "(null)",
table_name ? table_name : "(null)",
orig_table_name ? orig_table_name : "(null)",
field_name ? field_name : "(null)",
orig_field_name ? orig_field_name : "(null)"));
#endif
Item::cleanup();
db_name= orig_db_name;
table_name= orig_table_name;
field_name= orig_field_name;
DBUG_VOID_RETURN;
}
bool Item_ident::remove_dependence_processor(uchar * arg)
{
DBUG_ENTER("Item_ident::remove_dependence_processor");
if (depended_from == (st_select_lex *) arg)
depended_from= 0;
context= &((st_select_lex *) arg)->context;
DBUG_RETURN(0);
}
/**
Store the pointer to this item field into a list if not already there.
The method is used by Item::walk to collect all unique Item_field objects
from a tree of Items into a set of items represented as a list.
Item_cond::walk() and Item_func::walk() stop the evaluation of the
processor function for its arguments once the processor returns
true.Therefore in order to force this method being called for all item
arguments in a condition the method must return false.
@param arg pointer to a List<Item_field>
@return
FALSE to force the evaluation of collect_item_field_processor
for the subsequent items.
*/
bool Item_field::collect_item_field_processor(uchar *arg)
{
DBUG_ENTER("Item_field::collect_item_field_processor");
DBUG_PRINT("info", ("%s", field->field_name ? field->field_name : "noname"));
List<Item_field> *item_list= (List<Item_field>*) arg;
List_iterator<Item_field> item_list_it(*item_list);
Item_field *curr_item;
while ((curr_item= item_list_it++))
{
if (curr_item->eq(this, 1))
DBUG_RETURN(FALSE); /* Already in the set. */
}
item_list->push_back(this);
DBUG_RETURN(FALSE);
}
bool Item_field::add_field_to_set_processor(uchar *arg)
{
DBUG_ENTER("Item_field::add_field_to_set_processor");
DBUG_PRINT("info", ("%s", field->field_name ? field->field_name : "noname"));
TABLE *table= (TABLE *) arg;
if (field->table == table)
bitmap_set_bit(&table->tmp_set, field->field_index);
DBUG_RETURN(FALSE);
}
bool Item_field::remove_column_from_bitmap(uchar *argument)
{
MY_BITMAP *bitmap= reinterpret_cast<MY_BITMAP*>(argument);
bitmap_clear_bit(bitmap, field->field_index);
return false;
}
/**
Check if an Item_field references some field from a list of fields.
Check whether the Item_field represented by 'this' references any
of the fields in the keyparts passed via 'arg'. Used with the
method Item::walk() to test whether any keypart in a sequence of
keyparts is referenced in an expression.
@param arg Field being compared, arg must be of type Field
@retval
TRUE if 'this' references the field 'arg'
@retval
FALSE otherwise
*/
bool Item_field::find_item_in_field_list_processor(uchar *arg)
{
KEY_PART_INFO *first_non_group_part= *((KEY_PART_INFO **) arg);
KEY_PART_INFO *last_part= *(((KEY_PART_INFO **) arg) + 1);
KEY_PART_INFO *cur_part;
for (cur_part= first_non_group_part; cur_part != last_part; cur_part++)
{
if (field->eq(cur_part->field))
return TRUE;
}
return FALSE;
}
/*
Mark field in read_map
NOTES
This is used by filesort to register used fields in a a temporary
column read set or to register used fields in a view
*/
bool Item_field::register_field_in_read_map(uchar *arg)
{
TABLE *table= (TABLE *) arg;
if (field->table == table || !table)
bitmap_set_bit(field->table->read_set, field->field_index);
return 0;
}
bool Item::check_cols(uint c)
{
if (c != 1)
{
my_error(ER_OPERAND_COLUMNS, MYF(0), c);
return 1;
}
return 0;
}
const Name_string null_name_string(NULL, 0);
void Name_string::copy(const char *str, size_t length, const CHARSET_INFO *cs)
{
if (!length)
{
/* Empty string, used by AS or internal function like last_insert_id() */
set(str ? "" : NULL, 0);
return;
}
if (cs->ctype)
{
/*
This will probably need a better implementation in the future:
a function in CHARSET_INFO structure.
*/
while (length && !my_isgraph(cs, *str))