1
/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
2
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
4
* Copyright (C) 2008 Sun Microsystems
6
* This program is free software; you can redistribute it and/or modify
7
* it under the terms of the GNU General Public License as published by
8
* the Free Software Foundation; version 2 of the License.
10
* This program is distributed in the hope that it will be useful,
11
* but WITHOUT ANY WARRANTY; without even the implied warranty of
12
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13
* GNU General Public License for more details.
15
* You should have received a copy of the GNU General Public License
16
* along with this program; if not, write to the Free Software
17
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20
#ifndef DRIZZLED_FUNCTION_FUNC_H
21
#define DRIZZLED_FUNCTION_FUNC_H
23
/// TODO: Rename this file - func.h is stupid.
25
#include <drizzled/item.h>
26
#include <drizzled/sql_list.h>
27
#include <drizzled/item/bin_string.h>
28
#include "drizzled/current_session.h"
33
class Item_func :public Item_result_field
38
Item **args, *tmp_arg[2];
40
Allowed numbers of columns in result (usually 1, which means scalar value)
41
0 means get this number from first argument
43
uint32_t allowed_arg_cols;
46
using Item::split_sum_func;
49
table_map used_tables_cache, not_null_tables_cache;
50
bool const_item_cache;
51
enum Functype { UNKNOWN_FUNC,EQ_FUNC,EQUAL_FUNC,NE_FUNC,LT_FUNC,LE_FUNC,
53
LIKE_FUNC,ISNULL_FUNC,ISNOTNULL_FUNC,
54
COND_AND_FUNC, COND_OR_FUNC, COND_XOR_FUNC,
55
BETWEEN, IN_FUNC, MULT_EQUAL_FUNC,
56
INTERVAL_FUNC, ISNOTNULLTEST_FUNC,
57
NOT_FUNC, NOT_ALL_FUNC,
58
NOW_FUNC, TRIG_COND_FUNC,
59
SUSERVAR_FUNC, GUSERVAR_FUNC, COLLATE_FUNC,
60
EXTRACT_FUNC, CHAR_TYPECAST_FUNC, FUNC_SP,
62
enum optimize_type { OPTIMIZE_NONE,OPTIMIZE_KEY,OPTIMIZE_OP, OPTIMIZE_NULL,
64
enum Type type() const { return FUNC_ITEM; }
65
virtual enum Functype functype() const { return UNKNOWN_FUNC; }
66
virtual ~Item_func() {}
69
_session(*current_session),
70
allowed_arg_cols(1), arg_count(0)
73
collation.set(DERIVATION_SYSCONST);
77
_session(*current_session),
78
allowed_arg_cols(1), arg_count(1)
82
with_sum_func= a->with_sum_func;
83
collation.set(DERIVATION_SYSCONST);
86
Item_func(Item *a,Item *b):
87
_session(*current_session),
88
allowed_arg_cols(1), arg_count(2)
91
args[0]= a; args[1]= b;
92
with_sum_func= a->with_sum_func || b->with_sum_func;
93
collation.set(DERIVATION_SYSCONST);
96
Item_func(Item *a,Item *b,Item *c):
97
_session(*current_session),
101
if ((args= (Item**) memory::sql_alloc(sizeof(Item*)*3)))
104
args[0]= a; args[1]= b; args[2]= c;
105
with_sum_func= a->with_sum_func || b->with_sum_func || c->with_sum_func;
107
collation.set(DERIVATION_SYSCONST);
110
Item_func(Item *a,Item *b,Item *c,Item *d):
111
_session(*current_session),
115
if ((args= (Item**) memory::sql_alloc(sizeof(Item*)*4)))
118
args[0]= a; args[1]= b; args[2]= c; args[3]= d;
119
with_sum_func= a->with_sum_func || b->with_sum_func ||
120
c->with_sum_func || d->with_sum_func;
122
collation.set(DERIVATION_SYSCONST);
125
Item_func(Item *a,Item *b,Item *c,Item *d,Item* e):
126
_session(*current_session),
130
if ((args= (Item**) memory::sql_alloc(sizeof(Item*)*5)))
132
args[0]= a; args[1]= b; args[2]= c; args[3]= d; args[4]= e;
133
with_sum_func= a->with_sum_func || b->with_sum_func ||
134
c->with_sum_func || d->with_sum_func || e->with_sum_func ;
136
collation.set(DERIVATION_SYSCONST);
139
Item_func(List<Item> &list);
141
// Constructor used for Item_cond_and/or (see Item comment)
142
Item_func(Session *session, Item_func *item);
144
bool fix_fields(Session *, Item **ref);
145
void fix_after_pullout(Select_Lex *new_parent, Item **ref);
146
table_map used_tables() const;
147
table_map not_null_tables() const;
148
void update_used_tables();
149
bool eq(const Item *item, bool binary_cmp) const;
150
virtual optimize_type select_optimize() const { return OPTIMIZE_NONE; }
151
virtual bool have_rev_func() const { return 0; }
152
virtual Item *key_item() const { return args[0]; }
154
This method is used for debug purposes to print the name of an
155
item to the debug log. The second use of this method is as
156
a helper function of print(), where it is applicable.
157
To suit both goals it should return a meaningful,
158
distinguishable and sintactically correct string. This method
159
should not be used for runtime type identification, use enum
160
{Sum}Functype and Item_func::functype()/Item_sum::sum_func()
163
virtual const char *func_name() const { return NULL; }
164
virtual bool const_item() const { return const_item_cache; }
165
Item **arguments() const { return args; }
166
void set_arguments(List<Item> &list);
167
uint32_t argument_count() const { return arg_count; }
168
void remove_arguments() { arg_count=0; }
171
* Check if the UDF supports the number of arguments passed in
172
* @param number of args
174
virtual bool check_argument_count(int) { return true ; }
175
virtual void split_sum_func(Session *session, Item **ref_pointer_array,
178
virtual void print(String *str, enum_query_type query_type);
179
void print_op(String *str, enum_query_type query_type);
180
void print_args(String *str, uint32_t from, enum_query_type query_type);
181
virtual void fix_num_length_and_dec();
182
void count_only_length();
183
void count_real_length();
184
void count_decimal_length();
186
bool get_arg0_date(DRIZZLE_TIME *ltime, uint32_t fuzzy_date);
187
bool get_arg0_time(DRIZZLE_TIME *ltime);
191
void signal_divide_by_null();
193
virtual Field *tmp_table_field() { return result_field; }
194
virtual Field *tmp_table_field(Table *t_arg);
196
Item *get_tmp_table_item(Session *session);
198
my_decimal *val_decimal(my_decimal *);
200
bool agg_arg_collations(DTCollation &c, Item **items, uint32_t nitems,
202
bool agg_arg_collations_for_comparison(DTCollation &c,
203
Item **items, uint32_t nitems,
205
bool agg_arg_charsets(DTCollation &c, Item **items, uint32_t nitems,
206
uint32_t flags, int item_sep);
207
bool walk(Item_processor processor, bool walk_subquery, unsigned char *arg);
208
Item *transform(Item_transformer transformer, unsigned char *arg);
209
Item* compile(Item_analyzer analyzer, unsigned char **arg_p,
210
Item_transformer transformer, unsigned char *arg_t);
211
void traverse_cond(Cond_traverser traverser,
212
void * arg, traverse_order order);
213
double fix_result(double value);
215
Session &getSession()
220
Session *getSessionPtr()
227
} /* namespace drizzled */
230
#endif /* DRIZZLED_FUNCTION_FUNC_H */