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mariadb/sql/item.cc
unknown a3e71bdbf5 Merge for post-merge fixes for Item_equal patch. 
BitKeeper/etc/ignore:
  auto-union
mysql-test/r/range.result:
  Auto merged
mysql-test/r/select.result:
  Auto merged
mysql-test/t/range.test:
  Auto merged
sql/item.cc:
  Auto merged
sql/opt_range.cc:
  Auto merged
sql/opt_sum.cc:
  Auto merged
sql/sql_select.h:
  Auto merged
sql/item.h:
  Manual merge
sql/sql_select.cc:
  Manual merge
2004-10-19 16:07:10 -07:00

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/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
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; either version 2 of the License, or
(at your option) any later version.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifdef __GNUC__
#pragma implementation // gcc: Class implementation
#endif
#include "mysql_priv.h"
#include <m_ctype.h>
#include "my_dir.h"
#include "sp_rcontext.h"
#include "sql_acl.h"
#include "sp_head.h"
#include "sql_trigger.h"
static void mark_as_dependent(THD *thd,
SELECT_LEX *last, SELECT_LEX *current,
Item_ident *item);
const String my_null_string("NULL", 4, default_charset_info);
/*****************************************************************************
** Item functions
*****************************************************************************/
/* Init all special items */
void item_init(void)
{
item_user_lock_init();
}
Item::Item():
name_length(0), fixed(0)
{
marker= 0;
maybe_null=null_value=with_sum_func=unsigned_flag=0;
collation.set(default_charset(), DERIVATION_COERCIBLE);
name= 0;
decimals= 0; max_length= 0;
/* 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 & agregate (sum) functions.
Used for duplicating lists in processing queries with temporary
tables
*/
Item::Item(THD *thd, Item *item):
str_value(item->str_value),
name(item->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)
{
next= thd->free_list; // Put in free list
thd->free_list= this;
}
void Item::print_item_w_name(String *str)
{
print(str);
if (name)
{
THD *thd= current_thd;
str->append(" AS ", 4);
append_identifier(thd, str, name, strlen(name));
}
}
void Item::cleanup()
{
DBUG_ENTER("Item::cleanup");
DBUG_PRINT("info", ("Item: 0x%lx", this));
DBUG_PRINT("info", ("Type: %d", (int)type()));
fixed=0;
DBUG_VOID_RETURN;
}
Item_ident::Item_ident(const char *db_name_par,const char *table_name_par,
const char *field_name_par)
:orig_db_name(db_name_par), orig_table_name(table_name_par),
orig_field_name(field_name_par), changed_during_fix_field(0),
db_name(db_name_par), table_name(table_name_par),
field_name(field_name_par), cached_field_index(NO_CACHED_FIELD_INDEX),
cached_table(0), depended_from(0)
{
name = (char*) field_name_par;
}
// 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),
changed_during_fix_field(0),
db_name(item->db_name),
table_name(item->table_name),
field_name(item->field_name),
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");
DBUG_PRINT("enter", ("b:%s(%s), t:%s(%s), f:%s(%s)",
db_name, orig_db_name,
table_name, orig_table_name,
field_name, orig_field_name));
Item::cleanup();
if (changed_during_fix_field)
{
*changed_during_fix_field= this;
changed_during_fix_field= 0;
}
db_name= orig_db_name;
table_name= orig_table_name;
field_name= orig_field_name;
DBUG_VOID_RETURN;
}
bool Item_ident::remove_dependence_processor(byte * arg)
{
DBUG_ENTER("Item_ident::remove_dependence_processor");
if (depended_from == (st_select_lex *) arg)
depended_from= 0;
DBUG_RETURN(0);
}
/*
Store the pointer to this item field into a list if not already there.
SYNOPSIS
Item_field::collect_item_field_processor()
arg pointer to a List<Item_field>
DESCRIPTION
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.
IMPLEMENTATION
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.
RETURN
false to force the evaluation of collect_item_field_processor
for the subsequent items.
*/
bool Item_field::collect_item_field_processor(byte *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::check_cols(uint c)
{
if (c != 1)
{
my_error(ER_OPERAND_COLUMNS, MYF(0), c);
return 1;
}
return 0;
}
void Item::set_name(const char *str, uint length, CHARSET_INFO *cs)
{
if (!length)
{
/* Empty string, used by AS or internal function like last_insert_id() */
name= (char*) str;
name_length= 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))
{
uint32 res_length;
name= sql_strmake_with_convert(str, name_length= length, cs,
MAX_ALIAS_NAME, system_charset_info,
&res_length);
}
else
name= sql_strmake(str, (name_length= min(length,MAX_ALIAS_NAME)));
}
/*
This function is called when:
- Comparing items in the WHERE clause (when doing where optimization)
- When trying to find an ORDER BY/GROUP BY item in the SELECT part
*/
bool Item::eq(const Item *item, bool binary_cmp) const
{
return type() == item->type() && name && item->name &&
!my_strcasecmp(system_charset_info,name,item->name);
}
bool Item_string::eq(const Item *item, bool binary_cmp) const
{
if (type() == item->type())
{
if (binary_cmp)
return !stringcmp(&str_value, &item->str_value);
return !sortcmp(&str_value, &item->str_value, collation.collation);
}
return 0;
}
/*
Get the value of the function as a TIME structure.
As a extra convenience the time structure is reset on error!
*/
bool Item::get_date(TIME *ltime,uint fuzzydate)
{
char buff[40];
String tmp(buff,sizeof(buff), &my_charset_bin),*res;
if (!(res=val_str(&tmp)) ||
str_to_datetime_with_warn(res->ptr(), res->length(),
ltime, fuzzydate) <= MYSQL_TIMESTAMP_ERROR)
{
bzero((char*) ltime,sizeof(*ltime));
return 1;
}
return 0;
}
/*
Get time of first argument.
As a extra convenience the time structure is reset on error!
*/
bool Item::get_time(TIME *ltime)
{
char buff[40];
String tmp(buff,sizeof(buff),&my_charset_bin),*res;
if (!(res=val_str(&tmp)) ||
str_to_time_with_warn(res->ptr(), res->length(), ltime))
{
bzero((char*) ltime,sizeof(*ltime));
return 1;
}
return 0;
}
CHARSET_INFO *Item::default_charset()
{
return current_thd->variables.collation_connection;
}
int Item::save_in_field_no_warnings(Field *field, bool no_conversions)
{
int res;
THD *thd= field->table->in_use;
enum_check_fields tmp= thd->count_cuted_fields;
thd->count_cuted_fields= CHECK_FIELD_IGNORE;
res= save_in_field(field, no_conversions);
thd->count_cuted_fields= tmp;
return res;
}
Item *
Item_splocal::this_item()
{
THD *thd= current_thd;
return thd->spcont->get_item(m_offset);
}
Item *
Item_splocal::this_const_item() const
{
THD *thd= current_thd;
return thd->spcont->get_item(m_offset);
}
Item::Type
Item_splocal::type() const
{
THD *thd= current_thd;
if (thd->spcont)
return thd->spcont->get_item(m_offset)->type();
return NULL_ITEM; // Anything but SUBSELECT_ITEM
}
bool DTCollation::aggregate(DTCollation &dt, bool superset_conversion)
{
nagg++;
if (!my_charset_same(collation, dt.collation))
{
/*
We do allow to use binary strings (like BLOBS)
together with character strings.
Binaries have more precedance than a character
string of the same derivation.
*/
if (collation == &my_charset_bin)
{
if (derivation <= dt.derivation)
; // Do nothing
else
{
set(dt);
strong= nagg;
}
}
else if (dt.collation == &my_charset_bin)
{
if (dt.derivation <= derivation)
{
set(dt);
strong= nagg;
}
else
; // Do nothing
}
else if (superset_conversion)
{
if (derivation < dt.derivation &&
collation->state & MY_CS_UNICODE)
; // Do nothing
else if (dt.derivation < derivation &&
dt.collation->state & MY_CS_UNICODE)
{
set(dt);
strong= nagg;
}
else
{
// Cannot convert to superset
set(0, DERIVATION_NONE);
return 1;
}
}
else
{
set(0, DERIVATION_NONE);
return 1;
}
}
else if (derivation < dt.derivation)
{
// Do nothing
}
else if (dt.derivation < derivation)
{
set(dt);
strong= nagg;
}
else
{
if (collation == dt.collation)
{
// Do nothing
}
else
{
if (derivation == DERIVATION_EXPLICIT)
{
set(0, DERIVATION_NONE);
return 1;
}
CHARSET_INFO *bin= get_charset_by_csname(collation->csname,
MY_CS_BINSORT,MYF(0));
set(bin, DERIVATION_NONE);
}
}
return 0;
}
Item_field::Item_field(Field *f)
:Item_ident(NullS, f->table_name, f->field_name),
item_equal(0), no_const_subst(0),
have_privileges(0), any_privileges(0)
{
set_field(f);
collation.set(DERIVATION_IMPLICIT);
fixed= 1;
}
Item_field::Item_field(THD *thd, Field *f)
:Item_ident(NullS, thd->strdup(f->table_name),
thd->strdup(f->field_name)),
item_equal(0), no_const_subst(0),
have_privileges(0), any_privileges(0)
{
set_field(f);
collation.set(DERIVATION_IMPLICIT);
fixed= 1;
}
// Constructor need to process subselect with temporary tables (see Item)
Item_field::Item_field(THD *thd, Item_field *item)
:Item_ident(thd, item),
field(item->field),
result_field(item->result_field),
item_equal(item->item_equal),
no_const_subst(item->no_const_subst),
have_privileges(item->have_privileges),
any_privileges(item->any_privileges)
{
collation.set(DERIVATION_IMPLICIT);
}
void Item_field::set_field(Field *field_par)
{
field=result_field=field_par; // for easy coding with fields
maybe_null=field->maybe_null();
max_length=field_par->field_length;
decimals= field->decimals();
table_name=field_par->table_name;
field_name=field_par->field_name;
db_name=field_par->table->table_cache_key;
unsigned_flag=test(field_par->flags & UNSIGNED_FLAG);
collation.set(field_par->charset(), DERIVATION_IMPLICIT);
}
const char *Item_ident::full_name() const
{
char *tmp;
if (!table_name || !field_name)
return field_name ? field_name : name ? name : "tmp_field";
if (db_name && db_name[0])
{
tmp=(char*) sql_alloc((uint) strlen(db_name)+(uint) strlen(table_name)+
(uint) strlen(field_name)+3);
strxmov(tmp,db_name,".",table_name,".",field_name,NullS);
}
else
{
if (table_name[0])
{
tmp= (char*) sql_alloc((uint) strlen(table_name) +
(uint) strlen(field_name) + 2);
strxmov(tmp, table_name, ".", field_name, NullS);
}
else
tmp= (char*) field_name;
}
return tmp;
}
void Item_ident::print(String *str)
{
THD *thd= current_thd;
char d_name_buff[MAX_ALIAS_NAME], t_name_buff[MAX_ALIAS_NAME];
const char *d_name= db_name, *t_name= table_name;
if (lower_case_table_names)
{
if (table_name && table_name[0])
{
strmov(t_name_buff, table_name);
my_casedn_str(files_charset_info, t_name_buff);
t_name= t_name_buff;
}
if (db_name && db_name[0])
{
strmov(d_name_buff, db_name);
my_casedn_str(files_charset_info, d_name_buff);
d_name= d_name_buff;
}
}
if (!table_name || !field_name)
{
const char *nm= field_name ? field_name : name ? name : "tmp_field";
append_identifier(thd, str, nm, strlen(nm));
return;
}
if (db_name && db_name[0])
{
append_identifier(thd, str, d_name, strlen(d_name));
str->append('.');
append_identifier(thd, str, t_name, strlen(t_name));
str->append('.');
append_identifier(thd, str, field_name, strlen(field_name));
}
else
{
if (table_name[0])
{
append_identifier(thd, str, t_name, strlen(t_name));
str->append('.');
append_identifier(thd, str, field_name, strlen(field_name));
}
else
append_identifier(thd, str, field_name, strlen(field_name));
}
}
/* ARGSUSED */
String *Item_field::val_str(String *str)
{
DBUG_ASSERT(fixed == 1);
if ((null_value=field->is_null()))
return 0;
str->set_charset(str_value.charset());
return field->val_str(str,&str_value);
}
double Item_field::val()
{
DBUG_ASSERT(fixed == 1);
if ((null_value=field->is_null()))
return 0.0;
return field->val_real();
}
longlong Item_field::val_int()
{
DBUG_ASSERT(fixed == 1);
if ((null_value=field->is_null()))
return 0;
return field->val_int();
}
String *Item_field::str_result(String *str)
{
if ((null_value=result_field->is_null()))
return 0;
str->set_charset(str_value.charset());
return result_field->val_str(str,&str_value);
}
bool Item_field::get_date(TIME *ltime,uint fuzzydate)
{
if ((null_value=field->is_null()) || field->get_date(ltime,fuzzydate))
{
bzero((char*) ltime,sizeof(*ltime));
return 1;
}
return 0;
}
bool Item_field::get_date_result(TIME *ltime,uint fuzzydate)
{
if ((null_value=result_field->is_null()) ||
result_field->get_date(ltime,fuzzydate))
{
bzero((char*) ltime,sizeof(*ltime));
return 1;
}
return 0;
}
bool Item_field::get_time(TIME *ltime)
{
if ((null_value=field->is_null()) || field->get_time(ltime))
{
bzero((char*) ltime,sizeof(*ltime));
return 1;
}
return 0;
}
double Item_field::val_result()
{
if ((null_value=result_field->is_null()))
return 0.0;
return result_field->val_real();
}
longlong Item_field::val_int_result()
{
if ((null_value=result_field->is_null()))
return 0;
return result_field->val_int();
}
bool Item_field::eq(const Item *item, bool binary_cmp) const
{
if (item->type() != FIELD_ITEM)
return 0;
Item_field *item_field= (Item_field*) item;
if (item_field->field)
return item_field->field == field;
/*
We may come here when we are trying to find a function in a GROUP BY
clause from the select list.
In this case the '100 % correct' way to do this would be to first
run fix_fields() on the GROUP BY item and then retry this function, but
I think it's better to relax the checking a bit as we will in
most cases do the correct thing by just checking the field name.
(In cases where we would choose wrong we would have to generate a
ER_NON_UNIQ_ERROR).
*/
return (!my_strcasecmp(system_charset_info, item_field->name,
field_name) &&
(!item_field->table_name ||
(!my_strcasecmp(table_alias_charset, item_field->table_name,
table_name) &&
(!item_field->db_name ||
(item_field->db_name && !strcmp(item_field->db_name,
db_name))))));
}
table_map Item_field::used_tables() const
{
if (field->table->const_table)
return 0; // const item
return (depended_from ? OUTER_REF_TABLE_BIT : field->table->map);
}
Item *Item_field::get_tmp_table_item(THD *thd)
{
Item_field *new_item= new Item_field(thd, this);
if (new_item)
new_item->field= new_item->result_field;
return new_item;
}
/*
Create an item from a string we KNOW points to a valid longlong/ulonglong
end \0 terminated number string
*/
Item_int::Item_int(const char *str_arg, uint length)
{
char *end_ptr= (char*) str_arg + length;
int error;
value= my_strtoll10(str_arg, &end_ptr, &error);
max_length= (uint) (end_ptr - str_arg);
name= (char*) str_arg;
fixed= 1;
}
String *Item_int::val_str(String *str)
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
str->set(value, &my_charset_bin);
return str;
}
void Item_int::print(String *str)
{
// my_charset_bin is good enough for numbers
str_value.set(value, &my_charset_bin);
str->append(str_value);
}
Item_uint::Item_uint(const char *str_arg, uint length):
Item_int(str_arg, length)
{
unsigned_flag= 1;
}
String *Item_uint::val_str(String *str)
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
str->set((ulonglong) value, &my_charset_bin);
return str;
}
void Item_uint::print(String *str)
{
// latin1 is good enough for numbers
str_value.set((ulonglong) value, default_charset());
str->append(str_value);
}
String *Item_real::val_str(String *str)
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
str->set(value,decimals,&my_charset_bin);
return str;
}
void Item_string::print(String *str)
{
str->append('_');
str->append(collation.collation->csname);
str->append('\'');
str_value.print(str);
str->append('\'');
}
bool Item_null::eq(const Item *item, bool binary_cmp) const
{ return item->type() == type(); }
double Item_null::val()
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
null_value=1;
return 0.0;
}
longlong Item_null::val_int()
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
null_value=1;
return 0;
}
/* ARGSUSED */
String *Item_null::val_str(String *str)
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
null_value=1;
return 0;
}
/*********************** Item_param related ******************************/
/*
Default function of Item_param::set_param_func, so in case
of malformed packet the server won't SIGSEGV
*/
static void
default_set_param_func(Item_param *param,
uchar **pos __attribute__((unused)),
ulong len __attribute__((unused)))
{
param->set_null();
}
Item_param::Item_param(unsigned pos_in_query_arg) :
state(NO_VALUE),
item_result_type(STRING_RESULT),
/* Don't pretend to be a literal unless value for this item is set. */
item_type(PARAM_ITEM),
param_type(MYSQL_TYPE_STRING),
pos_in_query(pos_in_query_arg),
set_param_func(default_set_param_func)
{
name= (char*) "?";
/*
Since we can't say whenever this item can be NULL or cannot be NULL
before mysql_stmt_execute(), so we assuming that it can be NULL until
value is set.
*/
maybe_null= 1;
}
void Item_param::set_null()
{
DBUG_ENTER("Item_param::set_null");
/* These are cleared after each execution by reset() method */
max_length= 0;
null_value= 1;
/*
Because of NULL and string values we need to set max_length for each new
placeholder value: user can submit NULL for any placeholder type, and
string length can be different in each execution.
*/
max_length= 0;
decimals= 0;
state= NULL_VALUE;
DBUG_VOID_RETURN;
}
void Item_param::set_int(longlong i, uint32 max_length_arg)
{
DBUG_ENTER("Item_param::set_int");
value.integer= (longlong) i;
state= INT_VALUE;
max_length= max_length_arg;
decimals= 0;
maybe_null= 0;
DBUG_VOID_RETURN;
}
void Item_param::set_double(double d)
{
DBUG_ENTER("Item_param::set_double");
value.real= d;
state= REAL_VALUE;
max_length= DBL_DIG + 8;
decimals= NOT_FIXED_DEC;
maybe_null= 0;
DBUG_VOID_RETURN;
}
void Item_param::set_time(TIME *tm, timestamp_type type, uint32 max_length_arg)
{
DBUG_ENTER("Item_param::set_time");
value.time= *tm;
value.time.time_type= type;
state= TIME_VALUE;
maybe_null= 0;
max_length= max_length_arg;
decimals= 0;
DBUG_VOID_RETURN;
}
bool Item_param::set_str(const char *str, ulong length)
{
DBUG_ENTER("Item_param::set_str");
/*
Assign string with no conversion: data is converted only after it's
been written to the binary log.
*/
if (str_value.copy(str, length, &my_charset_bin, &my_charset_bin))
DBUG_RETURN(TRUE);
state= STRING_VALUE;
maybe_null= 0;
/* max_length and decimals are set after charset conversion */
/* sic: str may be not null-terminated, don't add DBUG_PRINT here */
DBUG_RETURN(FALSE);
}
bool Item_param::set_longdata(const char *str, ulong length)
{
DBUG_ENTER("Item_param::set_longdata");
/*
If client character set is multibyte, end of long data packet
may hit at the middle of a multibyte character. Additionally,
if binary log is open we must write long data value to the
binary log in character set of client. This is why we can't
convert long data to connection character set as it comes
(here), and first have to concatenate all pieces together,
write query to the binary log and only then perform conversion.
*/
if (str_value.append(str, length, &my_charset_bin))
DBUG_RETURN(TRUE);
state= LONG_DATA_VALUE;
maybe_null= 0;
DBUG_RETURN(FALSE);
}
/*
Set parameter value from user variable value.
SYNOPSIS
set_from_user_var
thd Current thread
entry User variable structure (NULL means use NULL value)
RETURN
0 OK
1 Out of memort
*/
bool Item_param::set_from_user_var(THD *thd, const user_var_entry *entry)
{
DBUG_ENTER("Item_param::set_from_user_var");
if (entry && entry->value)
{
item_result_type= entry->type;
switch (entry->type) {
case REAL_RESULT:
set_double(*(double*)entry->value);
item_type= Item::REAL_ITEM;
item_result_type= REAL_RESULT;
break;
case INT_RESULT:
set_int(*(longlong*)entry->value, 21);
item_type= Item::INT_ITEM;
item_result_type= INT_RESULT;
break;
case STRING_RESULT:
{
CHARSET_INFO *fromcs= entry->collation.collation;
CHARSET_INFO *tocs= thd->variables.collation_connection;
uint32 dummy_offset;
value.cs_info.character_set_client= fromcs;
/*
Setup source and destination character sets so that they
are different only if conversion is necessary: this will
make later checks easier.
*/
value.cs_info.final_character_set_of_str_value=
String::needs_conversion(0, fromcs, tocs, &dummy_offset) ?
tocs : fromcs;
/*
Exact value of max_length is not known unless data is converted to
charset of connection, so we have to set it later.
*/
item_type= Item::STRING_ITEM;
item_result_type= STRING_RESULT;
if (set_str((const char *)entry->value, entry->length))
DBUG_RETURN(1);
break;
}
default:
DBUG_ASSERT(0);
set_null();
}
}
else
set_null();
DBUG_RETURN(0);
}
/*
Resets parameter after execution.
SYNOPSIS
Item_param::reset()
NOTES
We clear null_value here instead of setting it in set_* methods,
because we want more easily handle case for long data.
*/
void Item_param::reset()
{
/* Shrink string buffer if it's bigger than max possible CHAR column */
if (str_value.alloced_length() > MAX_CHAR_WIDTH)
str_value.free();
else
str_value.length(0);
str_value_ptr.length(0);
/*
We must prevent all charset conversions untill data has been written
to the binary log.
*/
str_value.set_charset(&my_charset_bin);
state= NO_VALUE;
maybe_null= 1;
null_value= 0;
/*
Don't reset item_type to PARAM_ITEM: it's only needed to guard
us from item optimizations at prepare stage, when item doesn't yet
contain a literal of some kind.
In all other cases when this object is accessed its value is
set (this assumption is guarded by 'state' and
DBUG_ASSERTS(state != NO_VALUE) in all Item_param::get_*
methods).
*/
}
int Item_param::save_in_field(Field *field, bool no_conversions)
{
field->set_notnull();
switch (state) {
case INT_VALUE:
return field->store(value.integer);
case REAL_VALUE:
return field->store(value.real);
case TIME_VALUE:
field->store_time(&value.time, value.time.time_type);
return 0;
case STRING_VALUE:
case LONG_DATA_VALUE:
return field->store(str_value.ptr(), str_value.length(),
str_value.charset());
case NULL_VALUE:
return set_field_to_null(field);
case NO_VALUE:
default:
DBUG_ASSERT(0);
}
return 1;
}
bool Item_param::get_time(TIME *res)
{
if (state == TIME_VALUE)
{
*res= value.time;
return 0;
}
/*
If parameter value isn't supplied assertion will fire in val_str()
which is called from Item::get_time().
*/
return Item::get_time(res);
}
bool Item_param::get_date(TIME *res, uint fuzzydate)
{
if (state == TIME_VALUE)
{
*res= value.time;
return 0;
}
return Item::get_date(res, fuzzydate);
}
double Item_param::val()
{
switch (state) {
case REAL_VALUE:
return value.real;
case INT_VALUE:
return (double) value.integer;
case STRING_VALUE:
case LONG_DATA_VALUE:
{
int dummy_err;
return my_strntod(str_value.charset(), (char*) str_value.ptr(),
str_value.length(), (char**) 0, &dummy_err);
}
case TIME_VALUE:
/*
This works for example when user says SELECT ?+0.0 and supplies
time value for the placeholder.
*/
return ulonglong2double(TIME_to_ulonglong(&value.time));
case NULL_VALUE:
return 0.0;
default:
DBUG_ASSERT(0);
}
return 0.0;
}
longlong Item_param::val_int()
{
switch (state) {
case REAL_VALUE:
return (longlong) (value.real + (value.real > 0 ? 0.5 : -0.5));
case INT_VALUE:
return value.integer;
case STRING_VALUE:
case LONG_DATA_VALUE:
{
int dummy_err;
return my_strntoll(str_value.charset(), str_value.ptr(),
str_value.length(), 10, (char**) 0, &dummy_err);
}
case TIME_VALUE:
return (longlong) TIME_to_ulonglong(&value.time);
case NULL_VALUE:
return 0;
default:
DBUG_ASSERT(0);
}
return 0;
}
String *Item_param::val_str(String* str)
{
switch (state) {
case STRING_VALUE:
case LONG_DATA_VALUE:
return &str_value_ptr;
case REAL_VALUE:
str->set(value.real, NOT_FIXED_DEC, &my_charset_bin);
return str;
case INT_VALUE:
str->set(value.integer, &my_charset_bin);
return str;
case TIME_VALUE:
{
if (str->reserve(MAX_DATE_REP_LENGTH))
break;
TIME_to_string(&value.time, str);
return str;
}
case NULL_VALUE:
return NULL;
default:
DBUG_ASSERT(0);
}
return str;
}
/*
Return Param item values in string format, for generating the dynamic
query used in update/binary logs
TODO: change interface and implementation to fill log data in place
and avoid one more memcpy/alloc between str and log string.
*/
const String *Item_param::query_val_str(String* str) const
{
switch (state) {
case INT_VALUE:
str->set(value.integer, &my_charset_bin);
break;
case REAL_VALUE:
str->set(value.real, NOT_FIXED_DEC, &my_charset_bin);
break;
case TIME_VALUE:
{
char *buf, *ptr;
String tmp;
str->length(0);
/*
TODO: in case of error we need to notify replication
that binary log contains wrong statement
*/
if (str->reserve(MAX_DATE_REP_LENGTH+3))
break;
/* Create date string inplace */
buf= str->c_ptr_quick();
ptr= buf;
*ptr++= '\'';
tmp.set(ptr, MAX_DATE_REP_LENGTH, &my_charset_bin);
tmp.length(0);
TIME_to_string(&value.time, &tmp);
ptr+= tmp.length();
*ptr++= '\'';
str->length((uint32) (ptr - buf));
break;
}
case STRING_VALUE:
case LONG_DATA_VALUE:
{
char *buf, *ptr;
str->length(0);
if (str->reserve(str_value.length()*2+3))
break;
buf= str->c_ptr_quick();
ptr= buf;
*ptr++= '\'';
ptr+= escape_string_for_mysql(str_value.charset(), ptr,
str_value.ptr(), str_value.length());
*ptr++= '\'';
str->length(ptr - buf);
break;
}
case NULL_VALUE:
return &my_null_string;
default:
DBUG_ASSERT(0);
}
return str;
}
/*
Convert string from client character set to the character set of
connection.
*/
bool Item_param::convert_str_value(THD *thd)
{
bool rc= FALSE;
if (state == STRING_VALUE || state == LONG_DATA_VALUE)
{
/*
Check is so simple because all charsets were set up properly
in setup_one_conversion_function, where typecode of
placeholder was also taken into account: the variables are different
here only if conversion is really necessary.
*/
if (value.cs_info.final_character_set_of_str_value !=
value.cs_info.character_set_client)
{
rc= thd->convert_string(&str_value,
value.cs_info.character_set_client,
value.cs_info.final_character_set_of_str_value);
}
max_length= str_value.length();
decimals= 0;
/*
str_value_ptr is returned from val_str(). It must be not alloced
to prevent it's modification by val_str() invoker.
*/
str_value_ptr.set(str_value.ptr(), str_value.length(),
str_value.charset());
}
return rc;
}
void Item_param::print(String *str)
{
if (state == NO_VALUE)
{
str->append('?');
}
else
{
char buffer[80];
String tmp(buffer, sizeof(buffer), &my_charset_bin);
const String *res;
res= query_val_str(&tmp);
str->append(*res);
}
}
/****************************************************************************
Item_copy_string
****************************************************************************/
void Item_copy_string::copy()
{
String *res=item->val_str(&str_value);
if (res && res != &str_value)
str_value.copy(*res);
null_value=item->null_value;
}
/* ARGSUSED */
String *Item_copy_string::val_str(String *str)
{
// Item_copy_string is used without fix_fields call
if (null_value)
return (String*) 0;
return &str_value;
}
int Item_copy_string::save_in_field(Field *field, bool no_conversions)
{
if (null_value)
return set_field_to_null(field);
field->set_notnull();
return field->store(str_value.ptr(),str_value.length(),
collation.collation);
}
/*
Functions to convert item to field (for send_fields)
*/
/* ARGSUSED */
bool Item::fix_fields(THD *thd,
struct st_table_list *list,
Item ** ref)
{
// We do not check fields which are fixed during construction
DBUG_ASSERT(fixed == 0 || basic_const_item());
fixed= 1;
return 0;
}
double Item_ref_null_helper::val()
{
DBUG_ASSERT(fixed == 1);
double tmp= (*ref)->val_result();
owner->was_null|= null_value= (*ref)->null_value;
return tmp;
}
longlong Item_ref_null_helper::val_int()
{
DBUG_ASSERT(fixed == 1);
longlong tmp= (*ref)->val_int_result();
owner->was_null|= null_value= (*ref)->null_value;
return tmp;
}
String* Item_ref_null_helper::val_str(String* s)
{
DBUG_ASSERT(fixed == 1);
String* tmp= (*ref)->str_result(s);
owner->was_null|= null_value= (*ref)->null_value;
return tmp;
}
bool Item_ref_null_helper::get_date(TIME *ltime, uint fuzzydate)
{
return (owner->was_null|= null_value= (*ref)->get_date(ltime, fuzzydate));
}
/*
Mark item and SELECT_LEXs as dependent if it is not outer resolving
SYNOPSIS
mark_as_dependent()
thd - thread handler
last - select from which current item depend
current - current select
item - item which should be marked
*/
static void mark_as_dependent(THD *thd, SELECT_LEX *last, SELECT_LEX *current,
Item_ident *item)
{
// store pointer on SELECT_LEX from wich item is dependent
item->depended_from= last;
current->mark_as_dependent(last);
if (thd->lex->describe & DESCRIBE_EXTENDED)
{
char warn_buff[MYSQL_ERRMSG_SIZE];
sprintf(warn_buff, ER(ER_WARN_FIELD_RESOLVED),
(item->db_name?item->db_name:""), (item->db_name?".":""),
(item->table_name?item->table_name:""), (item->table_name?".":""),
item->field_name,
current->select_number, last->select_number);
push_warning(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
ER_WARN_FIELD_RESOLVED, warn_buff);
}
}
bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
{
DBUG_ASSERT(fixed == 0);
if (!field) // If field is not checked
{
bool upward_lookup= 0;
Field *tmp= (Field *)not_found_field;
if ((tmp= find_field_in_tables(thd, this, tables, ref, 0,
!any_privileges)) ==
not_found_field)
{
/*
We can't find table field in table list of current select,
consequently we have to find it in outer subselect(s).
We can't join lists of outer & current select, because of scope
of view rules. For example if both tables (outer & current) have
field 'field' it is not mistake to refer to this field without
mention of table name, but if we join tables in one list it will
cause error ER_NON_UNIQ_ERROR in find_field_in_tables.
*/
SELECT_LEX *last= 0;
#ifdef EMBEDDED_LIBRARY
thd->net.last_errno= 0;
#endif
TABLE_LIST *table_list;
Item **refer= (Item **)not_found_item;
uint counter;
// Prevent using outer fields in subselects, that is not supported now
SELECT_LEX *cursel= (SELECT_LEX *) thd->lex->current_select;
if (cursel->master_unit()->first_select()->linkage != DERIVED_TABLE_TYPE)
{
SELECT_LEX_UNIT *prev_unit= cursel->master_unit();
for (SELECT_LEX *sl= prev_unit->outer_select();
sl;
sl= (prev_unit= sl->master_unit())->outer_select())
{
upward_lookup= 1;
table_list= (last= sl)->get_table_list();
if (sl->resolve_mode == SELECT_LEX::INSERT_MODE && table_list)
{
/*
it is primary INSERT st_select_lex => skip first table
resolving
*/
table_list= table_list->next_local;
}
Item_subselect *prev_subselect_item= prev_unit->item;
enum_parsing_place place= prev_subselect_item->parsing_place;
/*
check table fields only if subquery used somewhere out of HAVING
or SELECT list or outer SELECT do not use groupping (i.e. tables
are accessable)
*/
if (((place != IN_HAVING &&
place != SELECT_LIST) ||
(sl->with_sum_func == 0 && sl->group_list.elements == 0)) &&
(tmp= find_field_in_tables(thd, this,
table_list, ref,
0, 1)) != not_found_field)
{
if (tmp)
{
if (tmp != view_ref_found)
{
prev_subselect_item->used_tables_cache|= tmp->table->map;
prev_subselect_item->const_item_cache= 0;
}
else
{
prev_subselect_item->used_tables_cache|=
(*ref)->used_tables();
prev_subselect_item->const_item_cache&=
(*ref)->const_item();
}
}
break;
}
if (sl->resolve_mode == SELECT_LEX::SELECT_MODE &&
(refer= find_item_in_list(this, sl->item_list, &counter,
REPORT_EXCEPT_NOT_FOUND)) !=
(Item **) not_found_item)
{
if (*refer && (*refer)->fixed) // Avoid crash in case of error
{
prev_subselect_item->used_tables_cache|= (*refer)->used_tables();
prev_subselect_item->const_item_cache&= (*refer)->const_item();
}
break;
}
// Reference is not found => depend from outer (or just error)
prev_subselect_item->used_tables_cache|= OUTER_REF_TABLE_BIT;
prev_subselect_item->const_item_cache= 0;
if (sl->master_unit()->first_select()->linkage ==
DERIVED_TABLE_TYPE)
break; // do not look over derived table
}
}
if (!tmp)
return -1;
if (!refer)
return 1;
if (tmp == not_found_field && refer == (Item **)not_found_item)
{
if (upward_lookup)
{
// We can't say exactly what absend table or field
my_printf_error(ER_BAD_FIELD_ERROR, ER(ER_BAD_FIELD_ERROR), MYF(0),
full_name(), thd->where);
}
else
{
// Call to report error
find_field_in_tables(thd, this, tables, ref, 1, 1);
}
return -1;
}
else if (refer != (Item **)not_found_item)
{
if (!(*refer)->fixed)
{
my_error(ER_ILLEGAL_REFERENCE, MYF(0), name,
"forward reference in item list");
return -1;
}
Item_ref *rf;
*ref= rf= new Item_ref(last->ref_pointer_array + counter,
ref,
(char *)table_name,
(char *)field_name);
register_item_tree_changing(ref);
if (!rf)
return 1;
/*
rf is Item_ref => never substitute other items (in this case)
during fix_fields() => we can use rf after fix_fields()
*/
if (rf->fix_fields(thd, tables, ref) || rf->check_cols(1))
return 1;
mark_as_dependent(thd, last, cursel, rf);
return 0;
}
else
{
mark_as_dependent(thd, last, cursel, this);
if (last->having_fix_field)
{
Item_ref *rf;
*ref= rf= new Item_ref(ref, *ref,
(cached_table->db[0]?cached_table->db:0),
(char *)cached_table->alias,
(char *)field_name);
if (!rf)
return 1;
/*
rf is Item_ref => never substitute other items (in this case)
during fix_fields() => we can use rf after fix_fields()
*/
return rf->fix_fields(thd, tables, ref) || rf->check_cols(1);
}
}
}
else if (!tmp)
return -1;
/*
if it is not expression from merged VIEW we will set this field.
We can leave expression substituted from view for next PS/SP rexecution
(i.e. do not register this substitution for reverting on cleupup()
(register_item_tree_changing())), because this subtree will be
fix_field'ed during setup_tables()->setup_ancestor() (i.e. before
all other expressions of query, and references on tables which do
not present in query will not make problems.
Also we suppose that view can't be changed during PS/SP life.
*/
if (tmp != view_ref_found)
set_field(tmp);
}
else if (thd->set_query_id && field->query_id != thd->query_id)
{
/* We only come here in unions */
TABLE *table=field->table;
field->query_id=thd->query_id;
table->used_fields++;
table->used_keys.intersect(field->part_of_key);
}
#ifndef NO_EMBEDDED_ACCESS_CHECKS
if (any_privileges)
{
char *db, *tab;
if (cached_table->view)
{
db= cached_table->view_db.str;
tab= cached_table->view_name.str;
}
else
{
db= cached_table->db;
tab= cached_table->real_name;
}
if (!(have_privileges= (get_column_grant(thd, &field->table->grant,
db, tab, field_name) &
VIEW_ANY_ACL)))
{
my_printf_error(ER_COLUMNACCESS_DENIED_ERROR,
ER(ER_COLUMNACCESS_DENIED_ERROR),
MYF(0),
"ANY",
thd->priv_user,
thd->host_or_ip,
field_name,
tab);
return 1;
}
}
#endif
fixed= 1;
return 0;
}
void Item_field::cleanup()
{
DBUG_ENTER("Item_field::cleanup");
Item_ident::cleanup();
/*
Even if this object was created by direct link to field in setup_wild()
it will be linked correctly next tyme by name of field and table alias.
I.e. we can drop 'field'.
*/
field= result_field= 0;
}
/*
Find a field among specified multiple equalities
SYNOPSIS
find_item_equal()
cond_equal reference to list of multiple equalities where
the field (this object) is to be looked for
DESCRIPTION
The function first searches the field among multiple equalities
of the current level (in the cond_equal->current_level list).
If it fails, it continues searching in upper levels accessed
through a pointer cond_equal->upper_levels.
The search terminates as soon as a multiple equality containing
the field is found.
RETURN VALUES
First Item_equal containing the field, if success
0, otherwise
*/
Item_equal *Item_field::find_item_equal(COND_EQUAL *cond_equal)
{
Item_equal *item= 0;
while (cond_equal)
{
List_iterator_fast<Item_equal> li(cond_equal->current_level);
while ((item= li++))
{
if (item->contains(field))
return item;
}
/*
The field is not found in any of the multiple equalities
of the current level. Look for it in upper levels
*/
cond_equal= cond_equal->upper_levels;
}
return 0;
}
/*
Set a pointer to the multiple equality the field reference belongs to (if any)
SYNOPSIS
equal_fields_propagator()
arg - reference to list of multiple equalities where
the field (this object) is to be looked for
DESCRIPTION
The function looks for a multiple equality containing the field item
among those referenced by arg.
In the case such equality exists the function does the following.
If the found multiple equality contains a constant, then the field
reference is substituted for this constant, otherwise it sets a pointer
to the multiple equality in the field item.
NOTES
This function is supposed to be called as a callback parameter in calls
of the transform method.
RETURN VALUES
pointer to the replacing constant item, if the field item was substituted
pointer to the field item, otherwise.
*/
Item *Item_field::equal_fields_propagator(byte *arg)
{
if (no_const_subst)
return this;
item_equal= find_item_equal((COND_EQUAL *) arg);
Item *item= 0;
if (item_equal)
item= item_equal->get_const();
if (!item)
item= this;
return item;
}
/*
Set a pointer to the multiple equality the field reference belongs to (if any)
SYNOPSIS
replace_equal_field_processor()
arg - a dummy parameter, is not used here
DESCRIPTION
The function replaces a pointer to a field in the Item_field object
by a pointer to another field.
The replacement field is taken from the very beginning of
the item_equal list which the Item_field object refers to (belongs to)
If the Item_field object does not refer any Item_equal object,
nothing is done.
NOTES
This function is supposed to be called as a callback parameter in calls
of the walk method.
RETURN VALUES
0
*/
bool Item_field::replace_equal_field_processor(byte *arg)
{
if (item_equal)
{
Item_field *subst= item_equal->get_first();
if (!field->eq(subst->field))
{
field= subst->field;
return 0;
}
}
return 0;
}
void Item::init_make_field(Send_field *tmp_field,
enum enum_field_types field_type)
{
char *empty_name= (char*) "";
tmp_field->db_name= empty_name;
tmp_field->org_table_name= empty_name;
tmp_field->org_col_name= empty_name;
tmp_field->table_name= empty_name;
tmp_field->col_name= name;
tmp_field->charsetnr= collation.collation->number;
tmp_field->flags=maybe_null ? 0 : NOT_NULL_FLAG;
tmp_field->type=field_type;
tmp_field->length=max_length;
tmp_field->decimals=decimals;
if (unsigned_flag)
tmp_field->flags |= UNSIGNED_FLAG;
}
void Item::make_field(Send_field *tmp_field)
{
init_make_field(tmp_field, field_type());
}
void Item_empty_string::make_field(Send_field *tmp_field)
{
init_make_field(tmp_field,FIELD_TYPE_VAR_STRING);
}
enum_field_types Item::field_type() const
{
return ((result_type() == STRING_RESULT) ? FIELD_TYPE_VAR_STRING :
(result_type() == INT_RESULT) ? FIELD_TYPE_LONGLONG :
FIELD_TYPE_DOUBLE);
}
Field *Item::tmp_table_field_from_field_type(TABLE *table)
{
/*
The field functions defines a field to be not null if null_ptr is not 0
*/
uchar *null_ptr= maybe_null ? (uchar*) "" : 0;
switch (field_type()) {
case MYSQL_TYPE_DECIMAL:
return new Field_decimal((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, decimals, 0, unsigned_flag);
case MYSQL_TYPE_TINY:
return new Field_tiny((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, 0, unsigned_flag);
case MYSQL_TYPE_SHORT:
return new Field_short((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, 0, unsigned_flag);
case MYSQL_TYPE_LONG:
return new Field_long((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, 0, unsigned_flag);
#ifdef HAVE_LONG_LONG
case MYSQL_TYPE_LONGLONG:
return new Field_longlong((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, 0, unsigned_flag);
#endif
case MYSQL_TYPE_FLOAT:
return new Field_float((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, decimals, 0, unsigned_flag);
case MYSQL_TYPE_DOUBLE:
return new Field_double((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, decimals, 0, unsigned_flag);
case MYSQL_TYPE_NULL:
return new Field_null((char*) 0, max_length, Field::NONE,
name, table, &my_charset_bin);
case MYSQL_TYPE_NEWDATE:
case MYSQL_TYPE_INT24:
return new Field_medium((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table, 0, unsigned_flag);
case MYSQL_TYPE_DATE:
return new Field_date(maybe_null, name, table, &my_charset_bin);
case MYSQL_TYPE_TIME:
return new Field_time(maybe_null, name, table, &my_charset_bin);
case MYSQL_TYPE_TIMESTAMP:
case MYSQL_TYPE_DATETIME:
return new Field_datetime(maybe_null, name, table, &my_charset_bin);
case MYSQL_TYPE_YEAR:
return new Field_year((char*) 0, max_length, null_ptr, 0, Field::NONE,
name, table);
default:
/* This case should never be choosen */
DBUG_ASSERT(0);
/* If something goes awfully wrong, it's better to get a string than die */
case MYSQL_TYPE_ENUM:
case MYSQL_TYPE_SET:
case MYSQL_TYPE_VAR_STRING:
if (max_length > 255)
break; // If blob
return new Field_varstring(max_length, maybe_null, name, table,
collation.collation);
case MYSQL_TYPE_STRING:
if (max_length > 255) // If blob
break;
return new Field_string(max_length, maybe_null, name, table,
collation.collation);
case MYSQL_TYPE_TINY_BLOB:
case MYSQL_TYPE_MEDIUM_BLOB:
case MYSQL_TYPE_LONG_BLOB:
case MYSQL_TYPE_BLOB:
case MYSQL_TYPE_GEOMETRY:
break; // Blob handled outside of case
}
/* blob is special as it's generated for both blobs and long strings */
return new Field_blob(max_length, maybe_null, name, table,
collation.collation);
}
/* ARGSUSED */
void Item_field::make_field(Send_field *tmp_field)
{
field->make_field(tmp_field);
DBUG_ASSERT(tmp_field->table_name);
if (name)
tmp_field->col_name=name; // Use user supplied name
}
/*
Set a field:s value from a item
*/
void Item_field::save_org_in_field(Field *to)
{
if (field->is_null())
{
null_value=1;
set_field_to_null_with_conversions(to, 1);
}
else
{
to->set_notnull();
field_conv(to,field);
null_value=0;
}
}
int Item_field::save_in_field(Field *to, bool no_conversions)
{
if (result_field->is_null())
{
null_value=1;
return set_field_to_null_with_conversions(to, no_conversions);
}
else
{
to->set_notnull();
field_conv(to,result_field);
null_value=0;
}
return 0;
}
/*
Store null in field
SYNOPSIS
save_in_field()
field Field where we want to store NULL
DESCRIPTION
This is used on INSERT.
Allow NULL to be inserted in timestamp and auto_increment values
RETURN VALUES
0 ok
1 Field doesn't support NULL values and can't handle 'field = NULL'
*/
int Item_null::save_in_field(Field *field, bool no_conversions)
{
return set_field_to_null_with_conversions(field, no_conversions);
}
/*
Store null in field
SYNOPSIS
save_safe_in_field()
field Field where we want to store NULL
RETURN VALUES
0 ok
1 Field doesn't support NULL values
*/
int Item_null::save_safe_in_field(Field *field)
{
return set_field_to_null(field);
}
int Item::save_in_field(Field *field, bool no_conversions)
{
int error;
if (result_type() == STRING_RESULT ||
result_type() == REAL_RESULT &&
field->result_type() == STRING_RESULT)
{
String *result;
CHARSET_INFO *cs= collation.collation;
char buff[MAX_FIELD_WIDTH]; // Alloc buffer for small columns
str_value.set_quick(buff, sizeof(buff), cs);
result=val_str(&str_value);
if (null_value)
{
str_value.set_quick(0, 0, cs);
return set_field_to_null_with_conversions(field, no_conversions);
}
field->set_notnull();
error=field->store(result->ptr(),result->length(),cs);
str_value.set_quick(0, 0, cs);
}
else if (result_type() == REAL_RESULT)
{
double nr=val();
if (null_value)
return set_field_to_null(field);
field->set_notnull();
error=field->store(nr);
}
else
{
longlong nr=val_int();
if (null_value)
return set_field_to_null_with_conversions(field, no_conversions);
field->set_notnull();
error=field->store(nr);
}
return error;
}
int Item_string::save_in_field(Field *field, bool no_conversions)
{
String *result;
result=val_str(&str_value);
if (null_value)
return set_field_to_null(field);
field->set_notnull();
return field->store(result->ptr(),result->length(),collation.collation);
}
int Item_uint::save_in_field(Field *field, bool no_conversions)
{
/*
TODO: To be fixed when wen have a
field->store(longlong, unsigned_flag) method
*/
return Item_int::save_in_field(field, no_conversions);
}
int Item_int::save_in_field(Field *field, bool no_conversions)
{
longlong nr=val_int();
if (null_value)
return set_field_to_null(field);
field->set_notnull();
return field->store(nr);
}
Item_num *Item_uint::neg()
{
return new Item_real(name, - ((double) value), 0, max_length);
}
/*
This function is only called during parsing. We will signal an error if
value is not a true double value (overflow)
*/
Item_real::Item_real(const char *str_arg, uint length)
{
int error;
char *end;
value= my_strntod(&my_charset_bin, (char*) str_arg, length, &end, &error);
if (error)
{
/*
Note that we depend on that str_arg is null terminated, which is true
when we are in the parser
*/
DBUG_ASSERT(str_arg[length] == 0);
my_printf_error(ER_ILLEGAL_VALUE_FOR_TYPE, ER(ER_ILLEGAL_VALUE_FOR_TYPE),
MYF(0), "double", (char*) str_arg);
}
presentation= name=(char*) str_arg;
decimals=(uint8) nr_of_decimals(str_arg);
max_length=length;
fixed= 1;
}
int Item_real::save_in_field(Field *field, bool no_conversions)
{
double nr=val();
if (null_value)
return set_field_to_null(field);
field->set_notnull();
return field->store(nr);
}
void Item_real::print(String *str)
{
if (presentation)
{
str->append(presentation);
return;
}
char buffer[20];
String num(buffer, sizeof(buffer), &my_charset_bin);
num.set(value, decimals, &my_charset_bin);
str->append(num);
}
/****************************************************************************
** varbinary item
** In string context this is a binary string
** In number context this is a longlong value.
****************************************************************************/
inline uint char_val(char X)
{
return (uint) (X >= '0' && X <= '9' ? X-'0' :
X >= 'A' && X <= 'Z' ? X-'A'+10 :
X-'a'+10);
}
Item_varbinary::Item_varbinary(const char *str, uint str_length)
{
name=(char*) str-2; // Lex makes this start with 0x
max_length=(str_length+1)/2;
char *ptr=(char*) sql_alloc(max_length+1);
if (!ptr)
return;
str_value.set(ptr,max_length,&my_charset_bin);
char *end=ptr+max_length;
if (max_length*2 != str_length)
*ptr++=char_val(*str++); // Not even, assume 0 prefix
while (ptr != end)
{
*ptr++= (char) (char_val(str[0])*16+char_val(str[1]));
str+=2;
}
*ptr=0; // Keep purify happy
collation.set(&my_charset_bin, DERIVATION_COERCIBLE);
fixed= 1;
}
longlong Item_varbinary::val_int()
{
// following assert is redundant, because fixed=1 assigned in constructor
DBUG_ASSERT(fixed == 1);
char *end=(char*) str_value.ptr()+str_value.length(),
*ptr=end-min(str_value.length(),sizeof(longlong));
ulonglong value=0;
for (; ptr != end ; ptr++)
value=(value << 8)+ (ulonglong) (uchar) *ptr;
return (longlong) value;
}
int Item_varbinary::save_in_field(Field *field, bool no_conversions)
{
int error;
field->set_notnull();
if (field->result_type() == STRING_RESULT)
{
error=field->store(str_value.ptr(),str_value.length(),collation.collation);
}
else
{
longlong nr=val_int();
error=field->store(nr);
}
return error;
}
/*
Pack data in buffer for sending
*/
bool Item_null::send(Protocol *protocol, String *packet)
{
return protocol->store_null();
}
/*
This is only called from items that is not of type item_field
*/
bool Item::send(Protocol *protocol, String *buffer)
{
bool result;
enum_field_types type;
LINT_INIT(result); // Will be set if null_value == 0
switch ((type=field_type())) {
default:
case MYSQL_TYPE_NULL:
case MYSQL_TYPE_DECIMAL:
case MYSQL_TYPE_ENUM:
case MYSQL_TYPE_SET:
case MYSQL_TYPE_TINY_BLOB:
case MYSQL_TYPE_MEDIUM_BLOB:
case MYSQL_TYPE_LONG_BLOB:
case MYSQL_TYPE_BLOB:
case MYSQL_TYPE_GEOMETRY:
case MYSQL_TYPE_STRING:
case MYSQL_TYPE_VAR_STRING:
{
String *res;
if ((res=val_str(buffer)))
result= protocol->store(res->ptr(),res->length(),res->charset());
break;
}
case MYSQL_TYPE_TINY:
{
longlong nr;
nr= val_int();
if (!null_value)
result= protocol->store_tiny(nr);
break;
}
case MYSQL_TYPE_SHORT:
{
longlong nr;
nr= val_int();
if (!null_value)
result= protocol->store_short(nr);
break;
}
case MYSQL_TYPE_INT24:
case MYSQL_TYPE_LONG:
{
longlong nr;
nr= val_int();
if (!null_value)
result= protocol->store_long(nr);
break;
}
case MYSQL_TYPE_LONGLONG:
{
longlong nr;
nr= val_int();
if (!null_value)
result= protocol->store_longlong(nr, unsigned_flag);
break;
}
case MYSQL_TYPE_FLOAT:
{
float nr;
nr= (float) val();
if (!null_value)
result= protocol->store(nr, decimals, buffer);
break;
}
case MYSQL_TYPE_DOUBLE:
{
double nr;
nr= val();
if (!null_value)
result= protocol->store(nr, decimals, buffer);
break;
}
case MYSQL_TYPE_DATETIME:
case MYSQL_TYPE_DATE:
case MYSQL_TYPE_TIMESTAMP:
{
TIME tm;
get_date(&tm, TIME_FUZZY_DATE);
if (!null_value)
{
if (type == MYSQL_TYPE_DATE)
return protocol->store_date(&tm);
else
result= protocol->store(&tm);
}
break;
}
case MYSQL_TYPE_TIME:
{
TIME tm;
get_time(&tm);
if (!null_value)
result= protocol->store_time(&tm);
break;
}
}
if (null_value)
result= protocol->store_null();
return result;
}
bool Item_field::send(Protocol *protocol, String *buffer)
{
return protocol->store(result_field);
}
/*
This is used for HAVING clause
Find field in select list having the same name
*/
bool Item_ref::fix_fields(THD *thd, TABLE_LIST *tables, Item **reference)
{
DBUG_ASSERT(fixed == 0);
uint counter;
if (!ref)
{
TABLE_LIST *table_list;
bool upward_lookup= 0;
SELECT_LEX_UNIT *prev_unit= thd->lex->current_select->master_unit();
SELECT_LEX *sl= prev_unit->outer_select();
/*
Finding only in current select will be performed for selects that have
not outer one and for derived tables (which not support using outer
fields for now)
*/
if ((ref= find_item_in_list(this,
*(thd->lex->current_select->get_item_list()),
&counter,
((sl &&
thd->lex->current_select->master_unit()->
first_select()->linkage !=
DERIVED_TABLE_TYPE) ?
REPORT_EXCEPT_NOT_FOUND :
REPORT_ALL_ERRORS))) ==
(Item **)not_found_item)
{
upward_lookup= 1;
Field *tmp= (Field*) not_found_field;
/*
We can't find table field in table list of current select,
consequently we have to find it in outer subselect(s).
We can't join lists of outer & current select, because of scope
of view rules. For example if both tables (outer & current) have
field 'field' it is not mistake to refer to this field without
mention of table name, but if we join tables in one list it will
cause error ER_NON_UNIQ_ERROR in find_item_in_list.
*/
SELECT_LEX *last=0;
for ( ; sl ; sl= (prev_unit= sl->master_unit())->outer_select())
{
last= sl;
Item_subselect *prev_subselect_item= prev_unit->item;
if (sl->resolve_mode == SELECT_LEX::SELECT_MODE &&
(ref= find_item_in_list(this, sl->item_list,
&counter,
REPORT_EXCEPT_NOT_FOUND)) !=
(Item **)not_found_item)
{
if (*ref && (*ref)->fixed) // Avoid crash in case of error
{
prev_subselect_item->used_tables_cache|= (*ref)->used_tables();
prev_subselect_item->const_item_cache&= (*ref)->const_item();
}
break;
}
table_list= sl->get_table_list();
if (sl->resolve_mode == SELECT_LEX::INSERT_MODE && table_list)
{
// it is primary INSERT st_select_lex => skip first table resolving
table_list= table_list->next_local;
}
enum_parsing_place place= prev_subselect_item->parsing_place;
/*
Check table fields only if subquery used somewhere out of HAVING
or SELECT list or outer SELECT do not use groupping (i.e. tables
are accessable)
*/
if (((place != IN_HAVING &&
place != SELECT_LIST) ||
(sl->with_sum_func == 0 && sl->group_list.elements == 0)) &&
(tmp= find_field_in_tables(thd, this,
table_list, reference,
0, 1)) != not_found_field)
{
if (tmp)
{
if (tmp != view_ref_found)
{
prev_subselect_item->used_tables_cache|= tmp->table->map;
prev_subselect_item->const_item_cache= 0;
}
else
{
prev_subselect_item->used_tables_cache|=
(*reference)->used_tables();
prev_subselect_item->const_item_cache&=
(*reference)->const_item();
}
}
break;
}
// Reference is not found => depend from outer (or just error)
prev_subselect_item->used_tables_cache|= OUTER_REF_TABLE_BIT;
prev_subselect_item->const_item_cache= 0;
if (sl->master_unit()->first_select()->linkage ==
DERIVED_TABLE_TYPE)
break; // do not look over derived table
}
if (!ref)
return 1;
else if (!tmp)
return -1;
else if (ref == (Item **)not_found_item && tmp == not_found_field)
{
if (upward_lookup)
{
// We can't say exactly what absend (table or field)
my_printf_error(ER_BAD_FIELD_ERROR, ER(ER_BAD_FIELD_ERROR), MYF(0),
full_name(), thd->where);
}
else
{
// Call to report error
find_item_in_list(this,
*(thd->lex->current_select->get_item_list()),
&counter,
REPORT_ALL_ERRORS);
}
ref= 0;
return 1;
}
else if (tmp != not_found_field)
{
ref= 0; // To prevent "delete *ref;" on ~Item_erf() of this item
if (tmp != view_ref_found)
{
Item_field* fld;
if (!((*reference)= fld= new Item_field(tmp)))
return 1;
mark_as_dependent(thd, last, thd->lex->current_select, fld);
register_item_tree_changing(reference);
return 0;
}
/*
We can leave expression substituted from view for next PS/SP
rexecution (i.e. do not register this substitution for reverting
on cleupup() (register_item_tree_changing())), because this
subtree will be fix_field'ed during
setup_tables()->setup_ancestor() (i.e. before all other
expressions of query, and references on tables which do not
present in query will not make problems.
Also we suppose that view can't be changed during PS/SP life.
*/
}
else
{
if (!(*ref)->fixed)
{
my_error(ER_ILLEGAL_REFERENCE, MYF(0), name,
"forward reference in item list");
return -1;
}
mark_as_dependent(thd, last, thd->lex->current_select,
this);
ref= last->ref_pointer_array + counter;
}
}
else if (!ref)
return 1;
else
{
if (!(*ref)->fixed)
{
my_error(ER_ILLEGAL_REFERENCE, MYF(0), name,
"forward reference in item list");
return -1;
}
ref= thd->lex->current_select->ref_pointer_array + counter;
}
}
/*
The following conditional is changed as to correctly identify
incorrect references in group functions or forward references
with sub-select's / derived tables, while it prevents this
check when Item_ref is created in an expression involving
summing function, which is to be placed in the user variable.
*/
if (((*ref)->with_sum_func && name &&
(depended_from ||
!(thd->lex->current_select->linkage != GLOBAL_OPTIONS_TYPE &&
thd->lex->current_select->having_fix_field))) ||
!(*ref)->fixed)
{
my_error(ER_ILLEGAL_REFERENCE, MYF(0), name,
((*ref)->with_sum_func?
"reference on group function":
"forward reference in item list"));
return 1;
}
max_length= (*ref)->max_length;
maybe_null= (*ref)->maybe_null;
decimals= (*ref)->decimals;
collation.set((*ref)->collation);
with_sum_func= (*ref)->with_sum_func;
fixed= 1;
if (ref && (*ref)->check_cols(1))
return 1;
return 0;
}
void Item_ref::cleanup()
{
DBUG_ENTER("Item_ref::cleanup");
Item_ident::cleanup();
result_field= 0;
if (hook_ptr)
*hook_ptr= orig_item;
DBUG_VOID_RETURN;
}
void Item_ref::print(String *str)
{
if (ref && *ref)
(*ref)->print(str);
else
Item_ident::print(str);
}
bool Item_ref::send(Protocol *prot, String *tmp)
{
if (result_field)
return prot->store(result_field);
return (*ref)->send(prot, tmp);
}
double Item_ref::val_result()
{
if (result_field)
{
if ((null_value= result_field->is_null()))
return 0.0;
return result_field->val_real();
}
return val();
}
longlong Item_ref::val_int_result()
{
if (result_field)
{
if ((null_value= result_field->is_null()))
return 0;
return result_field->val_int();
}
return val_int();
}
String *Item_ref::str_result(String* str)
{
if (result_field)
{
if ((null_value= result_field->is_null()))
return 0;
str->set_charset(str_value.charset());
return result_field->val_str(str, &str_value);
}
return val_str(str);
}
void Item_ref_null_helper::print(String *str)
{
str->append("<ref_null_helper>(", 18);
if (ref && *ref)
(*ref)->print(str);
else
str->append('?');
str->append(')');
}
void Item_null_helper::print(String *str)
{
str->append("<null_helper>(", 14);
store->print(str);
str->append(')');
}
bool Item_default_value::eq(const Item *item, bool binary_cmp) const
{
return item->type() == DEFAULT_VALUE_ITEM &&
((Item_default_value *)item)->arg->eq(arg, binary_cmp);
}
bool Item_default_value::fix_fields(THD *thd,
struct st_table_list *table_list,
Item **items)
{
Item_field *field_arg;
Field *def_field;
DBUG_ASSERT(fixed == 0);
if (!arg)
{
fixed= 1;
return 0;
}
if (arg->fix_fields(thd, table_list, &arg))
return 1;
if (arg->type() == REF_ITEM)
{
Item_ref *ref= (Item_ref *)arg;
if (ref->ref[0]->type() != FIELD_ITEM)
{
return 1;
}
arg= ref->ref[0];
}
field_arg= (Item_field *)arg;
if (field_arg->field->flags & NO_DEFAULT_VALUE_FLAG)
{
my_printf_error(ER_NO_DEFAULT_FOR_FIELD, ER(ER_NO_DEFAULT_FOR_FIELD),
MYF(0), field_arg->field->field_name);
return 1;
}
if (!(def_field= (Field*) sql_alloc(field_arg->field->size_of())))
return 1;
memcpy(def_field, field_arg->field, field_arg->field->size_of());
def_field->move_field(def_field->table->default_values -
def_field->table->record[0]);
set_field(def_field);
fixed= 1;
return 0;
}
void Item_default_value::print(String *str)
{
if (!arg)
{
str->append("default", 7);
return;
}
str->append("default(", 8);
arg->print(str);
str->append(')');
}
bool Item_insert_value::eq(const Item *item, bool binary_cmp) const
{
return item->type() == INSERT_VALUE_ITEM &&
((Item_default_value *)item)->arg->eq(arg, binary_cmp);
}
bool Item_insert_value::fix_fields(THD *thd,
struct st_table_list *table_list,
Item **items)
{
DBUG_ASSERT(fixed == 0);
if (arg->fix_fields(thd, table_list, &arg))
return 1;
if (arg->type() == REF_ITEM)
{
Item_ref *ref= (Item_ref *)arg;
if (ref->ref[0]->type() != FIELD_ITEM)
{
return 1;
}
arg= ref->ref[0];
}
Item_field *field_arg= (Item_field *)arg;
if (field_arg->field->table->insert_values)
{
Field *def_field= (Field*) sql_alloc(field_arg->field->size_of());
if (!def_field)
return 1;
memcpy(def_field, field_arg->field, field_arg->field->size_of());
def_field->move_field(def_field->table->insert_values -
def_field->table->record[0]);
set_field(def_field);
}
else
{
Field *tmp_field= field_arg->field;
/* charset doesn't matter here, it's to avoid sigsegv only */
set_field(new Field_null(0, 0, Field::NONE, tmp_field->field_name,
tmp_field->table, &my_charset_bin));
}
fixed= 1;
return 0;
}
void Item_insert_value::print(String *str)
{
str->append("values(", 7);
arg->print(str);
str->append(')');
}
/*
Bind item representing field of row being changed in trigger
to appropriate Field object.
SYNOPSIS
setup_field()
thd - current thread context
table - table of trigger (and where we looking for fields)
event - type of trigger event
NOTE
This function does almost the same as fix_fields() for Item_field
but is invoked during trigger definition parsing and takes TABLE
object as its argument.
RETURN VALUES
0 ok
1 field was not found.
*/
bool Item_trigger_field::setup_field(THD *thd, TABLE *table,
enum trg_event_type event)
{
bool result= 1;
uint field_idx= (uint)-1;
bool save_set_query_id= thd->set_query_id;
/* TODO: Think more about consequences of this step. */
thd->set_query_id= 0;
if (find_field_in_real_table(thd, table, field_name,
strlen(field_name), 0, 0,
&field_idx))
{
field= (row_version == OLD_ROW && event == TRG_EVENT_UPDATE) ?
table->triggers->old_field[field_idx] :
table->field[field_idx];
result= 0;
}
thd->set_query_id= save_set_query_id;
return result;
}
bool Item_trigger_field::eq(const Item *item, bool binary_cmp) const
{
return item->type() == TRIGGER_FIELD_ITEM &&
row_version == ((Item_trigger_field *)item)->row_version &&
!my_strcasecmp(system_charset_info, field_name,
((Item_trigger_field *)item)->field_name);
}
bool Item_trigger_field::fix_fields(THD *thd,
TABLE_LIST *table_list,
Item **items)
{
/*
Since trigger is object tightly associated with TABLE object most
of its set up can be performed during trigger loading i.e. trigger
parsing! So we have little to do in fix_fields. :)
FIXME may be we still should bother about permissions here.
*/
DBUG_ASSERT(fixed == 0);
// QQ: May be this should be moved to setup_field?
set_field(field);
fixed= 1;
return 0;
}
void Item_trigger_field::print(String *str)
{
str->append((row_version == NEW_ROW) ? "NEW" : "OLD", 3);
str->append('.');
str->append(field_name);
}
void Item_trigger_field::cleanup()
{
/*
Since special nature of Item_trigger_field we should not do most of
things from Item_field::cleanup() or Item_ident::cleanup() here.
*/
Item::cleanup();
}
/*
If item is a const function, calculate it and return a const item
The original item is freed if not returned
*/
Item_result item_cmp_type(Item_result a,Item_result b)
{
if (a == STRING_RESULT && b == STRING_RESULT)
return STRING_RESULT;
if (a == INT_RESULT && b == INT_RESULT)
return INT_RESULT;
else if (a == ROW_RESULT || b == ROW_RESULT)
return ROW_RESULT;
return REAL_RESULT;
}
Item *resolve_const_item(Item *item,Item *comp_item)
{
if (item->basic_const_item())
return item; // Can't be better
Item_result res_type=item_cmp_type(comp_item->result_type(),
item->result_type());
char *name=item->name; // Alloced by sql_alloc
if (res_type == STRING_RESULT)
{
char buff[MAX_FIELD_WIDTH];
String tmp(buff,sizeof(buff),&my_charset_bin),*result;
result=item->val_str(&tmp);
if (item->null_value)
return new Item_null(name);
uint length=result->length();
char *tmp_str=sql_strmake(result->ptr(),length);
return new Item_string(name,tmp_str,length,result->charset());
}
if (res_type == INT_RESULT)
{
longlong result=item->val_int();
uint length=item->max_length;
bool null_value=item->null_value;
return (null_value ? (Item*) new Item_null(name) :
(Item*) new Item_int(name,result,length));
}
else
{ // It must REAL_RESULT
double result=item->val();
uint length=item->max_length,decimals=item->decimals;
bool null_value=item->null_value;
return (null_value ? (Item*) new Item_null(name) :
(Item*) new Item_real(name,result,decimals,length));
}
}
/*
Return true if the value stored in the field is equal to the const item
We need to use this on the range optimizer because in some cases
we can't store the value in the field without some precision/character loss.
*/
bool field_is_equal_to_item(Field *field,Item *item)
{
Item_result res_type=item_cmp_type(field->result_type(),
item->result_type());
if (res_type == STRING_RESULT)
{
char item_buff[MAX_FIELD_WIDTH];
char field_buff[MAX_FIELD_WIDTH];
String item_tmp(item_buff,sizeof(item_buff),&my_charset_bin),*item_result;
String field_tmp(field_buff,sizeof(field_buff),&my_charset_bin);
item_result=item->val_str(&item_tmp);
if (item->null_value)
return 1; // This must be true
field->val_str(&field_tmp);
return !stringcmp(&field_tmp,item_result);
}
if (res_type == INT_RESULT)
return 1; // Both where of type int
double result=item->val();
if (item->null_value)
return 1;
return result == field->val_real();
}
Item_cache* Item_cache::get_cache(Item_result type)
{
switch (type)
{
case INT_RESULT:
return new Item_cache_int();
case REAL_RESULT:
return new Item_cache_real();
case STRING_RESULT:
return new Item_cache_str();
case ROW_RESULT:
return new Item_cache_row();
default:
// should never be in real life
DBUG_ASSERT(0);
return 0;
}
}
void Item_cache::print(String *str)
{
str->append("<cache>(", 8);
if (example)
example->print(str);
else
Item::print(str);
str->append(')');
}
void Item_cache_int::store(Item *item)
{
value= item->val_int_result();
null_value= item->null_value;
}
void Item_cache_real::store(Item *item)
{
value= item->val_result();
null_value= item->null_value;
}
void Item_cache_str::store(Item *item)
{
value_buff.set(buffer, sizeof(buffer), item->collation.collation);
value= item->str_result(&value_buff);
if ((null_value= item->null_value))
value= 0;
else if (value != &value_buff)
{
/*
We copy string value to avoid changing value if 'item' is table field
in queries like following (where t1.c is varchar):
select a,
(select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a'),
(select c from t1 where a=t2.a)
from t2;
*/
value_buff.copy(*value);
value= &value_buff;
}
}
double Item_cache_str::val()
{
DBUG_ASSERT(fixed == 1);
int err;
if (value)
return my_strntod(value->charset(), (char*) value->ptr(),
value->length(), (char**) 0, &err);
else
return (double)0;
}
longlong Item_cache_str::val_int()
{
DBUG_ASSERT(fixed == 1);
int err;
if (value)
return my_strntoll(value->charset(), value->ptr(),
value->length(), 10, (char**) 0, &err);
else
return (longlong)0;
}
bool Item_cache_row::allocate(uint num)
{
item_count= num;
THD *thd= current_thd;
return (!(values=
(Item_cache **) thd->calloc(sizeof(Item_cache *)*item_count)));
}
bool Item_cache_row::setup(Item * item)
{
example= item;
if (!values && allocate(item->cols()))
return 1;
for (uint i= 0; i < item_count; i++)
{
Item *el= item->el(i);
Item_cache *tmp;
if (!(tmp= values[i]= Item_cache::get_cache(el->result_type())))
return 1;
tmp->setup(el);
}
return 0;
}
void Item_cache_row::store(Item * item)
{
null_value= 0;
item->bring_value();
for (uint i= 0; i < item_count; i++)
{
values[i]->store(item->el(i));
null_value|= values[i]->null_value;
}
}
void Item_cache_row::illegal_method_call(const char *method)
{
DBUG_ENTER("Item_cache_row::illegal_method_call");
DBUG_PRINT("error", ("!!! %s method was called for row item", method));
DBUG_ASSERT(0);
my_error(ER_OPERAND_COLUMNS, MYF(0), 1);
DBUG_VOID_RETURN;
}
bool Item_cache_row::check_cols(uint c)
{
if (c != item_count)
{
my_error(ER_OPERAND_COLUMNS, MYF(0), c);
return 1;
}
return 0;
}
bool Item_cache_row::null_inside()
{
for (uint i= 0; i < item_count; i++)
{
if (values[i]->cols() > 1)
{
if (values[i]->null_inside())
return 1;
}
else
{
values[i]->val_int();
if (values[i]->null_value)
return 1;
}
}
return 0;
}
void Item_cache_row::bring_value()
{
for (uint i= 0; i < item_count; i++)
values[i]->bring_value();
return;
}
Item_type_holder::Item_type_holder(THD *thd, Item *item)
:Item(thd, item), item_type(item->result_type()),
orig_type(item_type)
{
DBUG_ASSERT(item->fixed);
/*
It is safe assign pointer on field, because it will be used just after
all JOIN::prepare calls and before any SELECT execution
*/
if (item->type() == Item::FIELD_ITEM)
field_example= ((Item_field*) item)->field;
else
field_example= 0;
max_length= real_length(item);
collation.set(item->collation);
}
/*
STRING_RESULT, REAL_RESULT, INT_RESULT, ROW_RESULT
ROW_RESULT should never appear in Item_type_holder::join_types,
but it is included in following table just to make table full
(there DBUG_ASSERT in function to catch ROW_RESULT)
*/
static Item_result type_convertor[4][4]=
{{STRING_RESULT, STRING_RESULT, STRING_RESULT, ROW_RESULT},
{STRING_RESULT, REAL_RESULT, REAL_RESULT, ROW_RESULT},
{STRING_RESULT, REAL_RESULT, INT_RESULT, ROW_RESULT},
{ROW_RESULT, ROW_RESULT, ROW_RESULT, ROW_RESULT}};
bool Item_type_holder::join_types(THD *thd, Item *item)
{
uint32 new_length= real_length(item);
bool change_field= 0, skip_store_field= 0;
Item_result new_type= type_convertor[item_type][item->result_type()];
// we have both fields
if (field_example && item->type() == Item::FIELD_ITEM)
{
Field *field= ((Item_field *)item)->field;
if (field_example->field_cast_type() != field->field_cast_type())
{
if (!(change_field=
field_example->field_cast_compatible(field->field_cast_type())))
{
/*
if old field can't store value of 'worse' new field we will make
decision about result field type based only on Item result type
*/
if (!field->field_cast_compatible(field_example->field_cast_type()))
skip_store_field= 1;
}
}
}
// size/type should be changed
if (change_field ||
(new_type != item_type) ||
(max_length < new_length) ||
((new_type == INT_RESULT) &&
(decimals < item->decimals)) ||
(!maybe_null && item->maybe_null) ||
(item_type == STRING_RESULT && new_type == STRING_RESULT &&
!my_charset_same(collation.collation, item->collation.collation)))
{
// new field has some parameters worse then current
skip_store_field|= (change_field &&
(max_length > new_length) ||
((new_type == INT_RESULT) &&
(decimals > item->decimals)) ||
(maybe_null && !item->maybe_null) ||
(item_type == STRING_RESULT &&
new_type == STRING_RESULT &&
!my_charset_same(collation.collation,
item->collation.collation)));
/*
It is safe assign pointer on field, because it will be used just after
all JOIN::prepare calls and before any SELECT execution
*/
if (skip_store_field || item->type() != Item::FIELD_ITEM)
field_example= 0;
else
field_example= ((Item_field*) item)->field;
const char *old_cs= collation.collation->name,
*old_derivation= collation.derivation_name();
if (item_type == STRING_RESULT && collation.aggregate(item->collation))
{
my_error(ER_CANT_AGGREGATE_2COLLATIONS, MYF(0),
old_cs, old_derivation,
item->collation.collation->name,
item->collation.derivation_name(),
"UNION");
return 1;
}
max_length= max(max_length, new_length);
decimals= max(decimals, item->decimals);
maybe_null|= item->maybe_null;
item_type= new_type;
}
DBUG_ASSERT(item_type != ROW_RESULT);
return 0;
}
uint32 Item_type_holder::real_length(Item *item)
{
if (item->type() == Item::FIELD_ITEM)
{
return ((Item_field *)item)->max_disp_length();
}
switch (item->result_type())
{
case STRING_RESULT:
return item->max_length;
case REAL_RESULT:
return 53;
case INT_RESULT:
return 20;
case ROW_RESULT:
default:
DBUG_ASSERT(0); // we should never go there
return 0;
}
}
double Item_type_holder::val()
{
DBUG_ASSERT(0); // should never be called
return 0.0;
}
longlong Item_type_holder::val_int()
{
DBUG_ASSERT(0); // should never be called
return 0;
}
String *Item_type_holder::val_str(String*)
{
DBUG_ASSERT(0); // should never be called
return 0;
}
/*****************************************************************************
** Instantiate templates
*****************************************************************************/
#ifdef __GNUC__
template class List<Item>;
template class List_iterator<Item>;
template class List_iterator_fast<Item>;
template class List<List_item>;
#endif
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