Drizzled Public API Documentation

sql_select.h
00001 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
00002  *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
00003  *
00004  *  Copyright (C) 2008-2009 Sun Microsystems, Inc.
00005  *
00006  *  This program is free software; you can redistribute it and/or modify
00007  *  it under the terms of the GNU General Public License as published by
00008  *  the Free Software Foundation; version 2 of the License.
00009  *
00010  *  This program is distributed in the hope that it will be useful,
00011  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  *  GNU General Public License for more details.
00014  *
00015  *  You should have received a copy of the GNU General Public License
00016  *  along with this program; if not, write to the Free Software
00017  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
00018  */
00019 
00020 #pragma once
00021 
00022 #include <drizzled/cached_item.h>
00023 #include <drizzled/field/varstring.h>
00024 #include <drizzled/item/null.h>
00025 #include <drizzled/enum_nested_loop_state.h>
00026 #include <drizzled/optimizer/position.h>
00027 #include <drizzled/optimizer/sargable_param.h>
00028 #include <drizzled/optimizer/key_use.h>
00029 #include <drizzled/join_cache.h>
00030 #include <drizzled/join_table.h>
00031 #include <drizzled/records.h>
00032 #include <drizzled/stored_key.h>
00033 
00034 #include <vector>
00035 
00036 namespace drizzled {
00037 
00042 /* PREV_BITS only used in sql_select.cc */
00043 #define PREV_BITS(type,A) ((type) (((type) 1 << (A)) -1))
00044 
00045 /* Values in optimize */
00046 #define KEY_OPTIMIZE_EXISTS   1
00047 #define KEY_OPTIMIZE_REF_OR_NULL  2
00048 
00049 enum_nested_loop_state sub_select_cache(Join *join, JoinTable *join_tab, bool end_of_records);
00050 enum_nested_loop_state sub_select(Join *join,JoinTable *join_tab, bool end_of_records);
00051 enum_nested_loop_state end_send_group(Join *join, JoinTable *join_tab, bool end_of_records);
00052 enum_nested_loop_state end_write_group(Join *join, JoinTable *join_tab, bool end_of_records);
00053 
00054 class Rollup
00055 {
00056 public:
00057   enum State { STATE_NONE, STATE_INITED, STATE_READY };
00058 
00059   Rollup()
00060   :
00061   state(),
00062   null_items(NULL),
00063   ref_pointer_arrays(NULL),
00064   fields()
00065   {}
00066   
00067   Rollup(State in_state,
00068          Item_null_result **in_null_items,
00069          Item ***in_ref_pointer_arrays,
00070          List<Item> *in_fields)
00071   :
00072   state(in_state),
00073   null_items(in_null_items),
00074   ref_pointer_arrays(in_ref_pointer_arrays),
00075   fields(in_fields)
00076   {}
00077   
00078   State getState() const
00079   {
00080     return state;
00081   }
00082 
00083   void setState(State in_state)
00084   {
00085     state= in_state;
00086   }
00087  
00088   Item_null_result **getNullItems() const
00089   {
00090     return null_items;
00091   }
00092 
00093   void setNullItems(Item_null_result **in_null_items)
00094   {
00095     null_items= in_null_items;
00096   }
00097 
00098   Item ***getRefPointerArrays() const
00099   {
00100     return ref_pointer_arrays;
00101   }
00102 
00103   void setRefPointerArrays(Item ***in_ref_pointer_arrays)
00104   {
00105     ref_pointer_arrays= in_ref_pointer_arrays;
00106   }
00107 
00108   List<Item> *getFields() const
00109   {
00110     return fields;
00111   }
00112 
00113   void setFields(List<Item> *in_fields)
00114   {
00115     fields= in_fields;
00116   }
00117   
00118 private:
00119   State state;
00120   Item_null_result **null_items;
00121   Item ***ref_pointer_arrays;
00122   List<Item> *fields;
00123 };
00124 
00125 } /* namespace drizzled */
00126 
00129 #include <drizzled/join.h>
00130 
00131 namespace drizzled
00132 {
00133 
00134 /*****************************************************************************
00135   Make som simple condition optimization:
00136   If there is a test 'field = const' change all refs to 'field' to 'const'
00137   Remove all dummy tests 'item = item', 'const op const'.
00138   Remove all 'item is NULL', when item can never be null!
00139   item->marker should be 0 for all items on entry
00140   Return in cond_value false if condition is impossible (1 = 2)
00141 *****************************************************************************/
00142 typedef std::pair<Item*, Item_func*> COND_CMP;
00143 
00144 void TEST_join(Join *join);
00145 
00146 /* Extern functions in sql_select.cc */
00147 bool store_val_in_field(Field *field, Item *val, enum_check_fields check_flag);
00148 Table *create_tmp_table(Session *session,Tmp_Table_Param *param,List<Item> &fields,
00149       Order *group, bool distinct, bool save_sum_fields,
00150       uint64_t select_options, ha_rows rows_limit,
00151       const char* alias);
00152 void count_field_types(Select_Lex *select_lex, Tmp_Table_Param *param,
00153                        List<Item> &fields, bool reset_with_sum_func);
00154 bool setup_copy_fields(Session *session, Tmp_Table_Param *param,
00155            Item **ref_pointer_array,
00156            List<Item> &new_list1, List<Item> &new_list2,
00157            uint32_t elements, List<Item> &fields);
00158 void copy_fields(Tmp_Table_Param *param);
00159 bool copy_funcs(Item **func_ptr, const Session *session);
00160 Field* create_tmp_field_from_field(Session *session, Field* org_field,
00161                                    const char *name, Table *table,
00162                                    Item_field *item, uint32_t convert_blob_length);
00163 bool test_if_ref(Item_field *left_item,Item *right_item);
00164 COND *optimize_cond(Join *join, COND *conds, List<TableList> *join_list, Item::cond_result *cond_value);
00165 COND *make_cond_for_table(COND *cond,table_map table, table_map used_table, bool exclude_expensive_cond);
00166 COND* substitute_for_best_equal_field(COND *cond, COND_EQUAL *cond_equal, void *table_join_idx);
00167 bool list_contains_unique_index(Table *table, bool (*find_func) (Field *, void *), void *data);
00168 bool find_field_in_order_list (Field *field, void *data);
00169 bool find_field_in_item_list (Field *field, void *data);
00170 bool test_if_skip_sort_order(JoinTable *tab,Order *order,ha_rows select_limit, bool no_changes, const key_map *map);
00171 Order *create_distinct_group(Session *session,
00172                                 Item **ref_pointer_array,
00173                                 Order *order_list,
00174                                 List<Item> &fields,
00175                                 List<Item> &,
00176                                 bool *all_order_by_fields_used);
00177 // Create list for using with tempory table
00178 bool change_to_use_tmp_fields(Session *session,
00179                               Item **ref_pointer_array,
00180                               List<Item> &res_selected_fields,
00181                               List<Item> &res_all_fields,
00182                               uint32_t elements,
00183                               List<Item> &all_fields);
00184 int do_select(Join *join, List<Item> *fields, Table *tmp_table);
00185 bool const_expression_in_where(COND *conds,Item *item, Item **comp_item);
00186 int create_sort_index(Session *session, Join *join, Order *order, ha_rows filesort_limit, ha_rows select_limit, bool is_order_by);
00187 void save_index_subquery_explain_info(JoinTable *join_tab, Item* where);
00188 Item *remove_additional_cond(Item* conds);
00189 bool setup_sum_funcs(Session *session, Item_sum **func_ptr);
00190 bool init_sum_functions(Item_sum **func, Item_sum **end);
00191 bool update_sum_func(Item_sum **func);
00192 void copy_sum_funcs(Item_sum **func_ptr, Item_sum **end);
00193 bool change_refs_to_tmp_fields(Session *session,
00194                                Item **ref_pointer_array,
00195                                List<Item> &res_selected_fields,
00196                                List<Item> &res_all_fields,
00197                                uint32_t elements,
00198                                List<Item> &all_fields);
00199 bool change_group_ref(Session *session, Item_func *expr, Order *group_list, bool *changed);
00200 bool check_interleaving_with_nj(JoinTable *next);
00201 void update_const_equal_items(COND *cond, JoinTable *tab);
00202 int join_read_const(JoinTable *tab);
00203 int join_read_key(JoinTable *tab);
00204 int join_read_always_key(JoinTable *tab);
00205 int join_read_last_key(JoinTable *tab);
00206 int join_no_more_records(ReadRecord *info);
00207 int join_read_next(ReadRecord *info);
00208 int join_read_next_different(ReadRecord *info);
00209 int join_init_quick_read_record(JoinTable *tab);
00210 int init_read_record_seq(JoinTable *tab);
00211 int test_if_quick_select(JoinTable *tab);
00212 int join_init_read_record(JoinTable *tab);
00213 int join_read_first(JoinTable *tab);
00214 int join_read_next_same(ReadRecord *info);
00215 int join_read_next_same_diff(ReadRecord *info);
00216 int join_read_last(JoinTable *tab);
00217 int join_read_prev_same(ReadRecord *info);
00218 int join_read_prev(ReadRecord *info);
00219 int join_read_always_key_or_null(JoinTable *tab);
00220 int join_read_next_same_or_null(ReadRecord *info);
00221 
00222 void calc_used_field_length(Session *, JoinTable *join_tab);
00223 StoredKey *get_store_key(Session *session, 
00224                          optimizer::KeyUse *keyuse,
00225                          table_map used_tables,
00226                          KeyPartInfo *key_part,
00227                          unsigned char *key_buff,
00228                          uint32_t maybe_null);
00229 int join_tab_cmp(const void* ptr1, const void* ptr2);
00230 int join_tab_cmp_straight(const void* ptr1, const void* ptr2);
00231 void push_index_cond(JoinTable *tab, uint32_t keyno, bool other_tbls_ok);
00232 void add_not_null_conds(Join *join);
00233 uint32_t max_part_bit(key_part_map bits);
00234 COND *add_found_match_trig_cond(JoinTable *tab, COND *cond, JoinTable *root_tab);
00235 bool eq_ref_table(Join *join, Order *start_order, JoinTable *tab);
00236 int remove_dup_with_compare(Session *session, Table *table, Field **first_field, uint32_t offset, Item *having);
00237 int remove_dup_with_hash_index(Session *session, 
00238                                Table *table,
00239                                uint32_t field_count,
00240                                Field **first_field,
00241                                uint32_t key_length,
00242                                Item *having);
00243 void update_ref_and_keys(Session *session,
00244                          DYNAMIC_ARRAY *keyuse,
00245                          JoinTable *join_tab,
00246                          uint32_t tables,
00247                          COND *cond, 
00248                          COND_EQUAL *,
00249                          table_map normal_tables,
00250                          Select_Lex *select_lex,
00251                          std::vector<optimizer::SargableParam> &sargables);
00252 ha_rows get_quick_record_count(Session *session, optimizer::SqlSelect *select, Table *table, const key_map *keys,ha_rows limit);
00253 void optimize_keyuse(Join *join, DYNAMIC_ARRAY *keyuse_array);
00254 void add_group_and_distinct_keys(Join *join, JoinTable *join_tab);
00255 void read_cached_record(JoinTable *tab);
00256 bool select_query(Session *session, Item ***rref_pointer_array,
00257                   TableList *tables, uint32_t wild_num,  List<Item> &list,
00258                   COND *conds, uint32_t og_num, Order *order, Order *group,
00259                   Item *having, uint64_t select_type,
00260                   select_result *result, Select_Lex_Unit *unit,
00261                   Select_Lex *select_lex);
00262 // Create list for using with tempory table
00263 void init_tmptable_sum_functions(Item_sum **func);
00264 void update_tmptable_sum_func(Item_sum **func,Table *tmp_table);
00265 bool only_eq_ref_tables(Join *join, Order *order, table_map tables);
00266 bool create_ref_for_key(Join *join, JoinTable *j, 
00267                         optimizer::KeyUse *org_keyuse, 
00268                         table_map used_tables);
00269 
00270 bool cp_buffer_from_ref(Session *session, table_reference_st *ref);
00271 int safe_index_read(JoinTable *tab);
00272 COND *remove_eq_conds(Session *session, COND *cond, Item::cond_result *cond_value);
00273 int test_if_item_cache_changed(List<Cached_item> &list);
00274 
00275 void print_join(Session *session, String *str, List<TableList> *tables);
00276 
00277 } /* namespace drizzled */
00278