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item.cc
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/*
Copyright (c) 2000, 2012, 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 "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)
{
if (!(collation.collation->state & MY_CS_NONASCII))
return val_str(str);
DBUG_ASSERT(str != &str_value);
uint errors;
String *res= val_str(&str_value);
if (!res)
return 0;
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))
{
my_decimal_set_zero(decimal_value);
null_value= 1; // set NULL, stop processing
return 0;
}
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), 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),
with_subselect(item->with_subselect),
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).
*/
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))
{ // Fix problem with yacc
length--;
str++;
}
}
if (!my_charset_same(cs, system_charset_info))
{
size_t res_length;
char *tmp= sql_strmake_with_convert(str, length, cs, MAX_ALIAS_NAME,
system_charset_info, &res_length);
set(tmp, tmp ? res_length : 0);
}
else
{
size_t len= min<size_t>(length, MAX_ALIAS_NAME);
char *tmp= sql_strmake(str, len);
set(tmp, tmp ? len : 0);