• unknown's avatar
    merging · 5fe662e2
    unknown authored
    include/mysqld_error.h:
      Auto merged
    mysql-test/r/subselect.result:
      Auto merged
    sql/item_subselect.cc:
      Auto merged
    sql/share/czech/errmsg.txt:
      Auto merged
    sql/share/danish/errmsg.txt:
      Auto merged
    sql/share/dutch/errmsg.txt:
      Auto merged
    sql/share/english/errmsg.txt:
      Auto merged
    sql/share/estonian/errmsg.txt:
      Auto merged
    sql/share/french/errmsg.txt:
      Auto merged
    sql/share/german/errmsg.txt:
      Auto merged
    sql/share/greek/errmsg.txt:
      Auto merged
    sql/sql_base.cc:
      Auto merged
    sql/sql_lex.cc:
      Auto merged
    sql/sql_yacc.yy:
      Auto merged
    sql/share/hungarian/errmsg.txt:
      Auto merged
    sql/share/italian/errmsg.txt:
      Auto merged
    sql/share/japanese/errmsg.txt:
      Auto merged
    sql/share/korean/errmsg.txt:
      Auto merged
    sql/share/norwegian-ny/errmsg.txt:
      Auto merged
    sql/share/norwegian/errmsg.txt:
      Auto merged
    sql/share/polish/errmsg.txt:
      Auto merged
    sql/share/portuguese/errmsg.txt:
      Auto merged
    sql/share/romanian/errmsg.txt:
      Auto merged
    sql/share/russian/errmsg.txt:
      Auto merged
    sql/share/serbian/errmsg.txt:
      Auto merged
    sql/share/slovak/errmsg.txt:
      Auto merged
    sql/share/spanish/errmsg.txt:
      Auto merged
    sql/share/swedish/errmsg.txt:
      Auto merged
    sql/share/ukrainian/errmsg.txt:
      Auto merged
    5fe662e2
item_subselect.cc 13.3 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556
/* Copyright (C) 2000 MySQL 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 */

/* 
   subselect Item

SUBSELECT TODO:
   - add function from mysql_select that use JOIN* as parameter to JOIN methods
     (sql_select.h/sql_select.cc)
   - remove double 'having' & 'having_list' from JOIN
     (sql_select.h/sql_select.cc)

*/

#ifdef __GNUC__
#pragma implementation				// gcc: Class implementation
#endif

#include "mysql_priv.h"
#include "sql_select.h"

Item_subselect::Item_subselect():
  Item_result_field(), engine_owner(1), value_assigned(0), substitution(0)
{
  assign_null();
  /*
    item value is NULL if select_subselect not changed this value 
    (i.e. some rows will be found returned)
  */
  null_value= 1;
}

void Item_subselect::init(THD *thd, st_select_lex *select_lex,
			  select_subselect *result)
{

  DBUG_ENTER("Item_subselect::init");
  DBUG_PRINT("subs", ("select_lex 0x%xl", (ulong) select_lex));

  select_transformer(select_lex);
  if (select_lex->next_select())
    engine= new subselect_union_engine(thd, select_lex->master_unit(), result,
				       this);
  else
    engine= new subselect_single_select_engine(thd, select_lex, result,
					       this);
  DBUG_VOID_RETURN;
}

Item_subselect::~Item_subselect()
{
  if (engine_owner)
    delete engine;
}

void Item_subselect::select_transformer(st_select_lex *select_lex) 
{
  DBUG_ENTER("Item_subselect::select_transformer");
  DBUG_VOID_RETURN;
}


void Item_subselect::make_field (Send_field *tmp_field)
{
  if (null_value)
  {
    init_make_field(tmp_field,FIELD_TYPE_NULL);
    tmp_field->length=4;
  } else {
    init_make_field(tmp_field, ((result_type() == STRING_RESULT) ?
				FIELD_TYPE_VAR_STRING :
				(result_type() == INT_RESULT) ?
				FIELD_TYPE_LONGLONG : FIELD_TYPE_DOUBLE));
  }
}

bool Item_subselect::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
{
  if (substitution)
  {
    (*ref)= substitution;
    engine->exclude();
    return substitution->fix_fields(thd, tables, ref);
  }

  char const *save_where= thd->where;
  int res= engine->prepare();
  if (!res)
  {
    // Is it one field subselect?
    if (engine->cols() > max_columns)
    {  
      my_error(ER_CARDINALITY_COL, MYF(0), 1);
      return 1;
    }
    fix_length_and_dec();
  }
  fixed= 1;
  thd->where= save_where;
  return res;
}

bool Item_subselect::check_loop(uint id)
{
  DBUG_ENTER("Item_subselect::check_loop");
  if (Item_result_field::check_loop(id))
    DBUG_RETURN(1);
  
  DBUG_RETURN(engine->check_loop(id));
}

void Item_subselect::fix_length_and_dec()
{
  engine->fix_length_and_dec();
}

inline table_map Item_subselect::used_tables() const
{
  return (table_map) engine->depended() ? 1L : 0L; 
}

Item_singleval_subselect::Item_singleval_subselect(THD *thd,
						   st_select_lex *select_lex):
  Item_subselect()
{
  DBUG_ENTER("Item_singleval_subselect::Item_singleval_subselect");
  init(thd, select_lex, new select_singleval_subselect(this));
  max_columns= 1;
  maybe_null= 1;
  DBUG_VOID_RETURN;
}

void Item_singleval_subselect::fix_length_and_dec()
{
  engine->fix_length_and_dec();
  res_type= engine->type();
}

Item::Type Item_subselect::type() const 
{
  return SUBSELECT_ITEM;
}

double Item_singleval_subselect::val () 
{
  if (engine->exec())
  {
    assign_null();
    return 0;
  }
  return real_value;
}

longlong Item_singleval_subselect::val_int () 
{
  if (engine->exec())
  {
    assign_null();
    return 0;
  }
  return int_value;
}

String *Item_singleval_subselect::val_str (String *str) 
{
  if (engine->exec() || null_value)
  {
    assign_null();
    return 0;
  }
  return &string_value;
}

Item_exists_subselect::Item_exists_subselect(THD *thd,
					     st_select_lex *select_lex):
  Item_subselect()
{
  DBUG_ENTER("Item_exists_subselect::Item_exists_subselect");
  init(thd, select_lex, new select_exists_subselect(this));
  max_columns= UINT_MAX;
  null_value= 0; //can't be NULL
  maybe_null= 0; //can't be NULL
  value= 0;
  // We need only 1 row to determinate existence
  select_lex->master_unit()->global_parameters->select_limit= 1;
  DBUG_VOID_RETURN;
}

Item_in_subselect::Item_in_subselect(THD *thd, Item * left_exp,
				     st_select_lex *select_lex):
  Item_exists_subselect()
{
  DBUG_ENTER("Item_in_subselect::Item_in_subselect");
  left_expr= left_exp;
  init(thd, select_lex, new select_exists_subselect(this));
  max_columns= UINT_MAX;
  null_value= 0; //can't be NULL
  maybe_null= 0; //can't be NULL
  value= 0;
  // We need only 1 row to determinate existence
  select_lex->master_unit()->global_parameters->select_limit= 1;
  DBUG_VOID_RETURN;
}

Item_allany_subselect::Item_allany_subselect(THD *thd, Item * left_exp,
					     compare_func_creator f,
					     st_select_lex *select_lex):
  Item_in_subselect()
{
  DBUG_ENTER("Item_in_subselect::Item_in_subselect");
  left_expr= left_exp;
  func= f;
  init(thd, select_lex, new select_exists_subselect(this));
  max_columns= UINT_MAX;
  null_value= 0; //can't be NULL
  maybe_null= 0; //can't be NULL
  value= 0;
  // We need only 1 row to determinate existence
  select_lex->master_unit()->global_parameters->select_limit= 1;
  DBUG_VOID_RETURN;
}


void Item_exists_subselect::fix_length_and_dec()
{
  max_length= 1;
}

double Item_exists_subselect::val () 
{
  if (engine->exec())
  {
    assign_null();
    return 0;
  }
  return (double) value;
}

longlong Item_exists_subselect::val_int () 
{
  if (engine->exec())
  {
    assign_null();
    return 0;
  }
  return value;
}

String *Item_exists_subselect::val_str(String *str)
{
  if (engine->exec())
  {
    assign_null();
    return 0;
  }
  str->set(value,thd_charset());
  return str;
}

Item_in_subselect::Item_in_subselect(Item_in_subselect *item):
  Item_exists_subselect(item)
{
  left_expr= item->left_expr;
}

Item_allany_subselect::Item_allany_subselect(Item_allany_subselect *item):
  Item_in_subselect(item)
{
  func= item->func;
}

void Item_in_subselect::single_value_transformer(st_select_lex *select_lex,
						 Item *left_expr,
						 compare_func_creator func)
{
  DBUG_ENTER("Item_in_subselect::single_value_transformer");
  for (SELECT_LEX * sl= select_lex; sl; sl= sl->next_select())
  {
    Item *item;
    if (sl->item_list.elements > 1)
    {
      my_error(ER_CARDINALITY_COL, MYF(0), 1);
      item= 0; // Item_asterisk_remover must fail
    }
    else
      item= (Item*) sl->item_list.pop();

    Item *expr= new Item_outer_select_context_saver(left_expr);

    if (sl->having || sl->with_sum_func || sl->group_list.first)
    {
      sl->item_list.push_back(item);
      item= (*func)(expr, new Item_ref(sl->item_list.head_ref(),
					    0, (char*)"<result>"));
      if (sl->having)
	sl->having= new Item_cond_and(sl->having, item);
      else
	sl->having= item;
    }
    else
    {
      sl->item_list.empty();
      sl->item_list.push_back(new Item_int(1));
      if (sl->table_list.elements)
      {
	item= (*func)(expr, new Item_asterisk_remover(item));
	if (sl->where)
	  sl->where= new Item_cond_and(sl->where, item);
	else
	  sl->where= item;
      }
      else
      {
	if (item->type() == Item::FIELD_ITEM &&
	    ((Item_field*) item)->field_name[0] == '*')
	{
	  my_error(ER_NO_TABLES_USED, MYF(0));
	  DBUG_VOID_RETURN;
	}
	if (select_lex->next_select())
	{
	  // it is in union => we should perform it
	  sl->having= (*func)(expr, item);
	}
	else
	{
	  // it is single select without tables => possible optimization
	  item= (*func)(left_expr, item);
	  substitution= item;
	  THD *thd= current_thd;
	  if (thd->lex.describe)
	  {
	    char warn_buff[MYSQL_ERRMSG_SIZE];
	    sprintf(warn_buff, ER(ER_SELECT_REDUCED), sl->select_number);
	    push_warning(thd, MYSQL_ERROR::WARN_LEVEL_NOTE,
			 ER_SELECT_REDUCED, warn_buff);
	  }
	}
      }
    }
  }
  DBUG_VOID_RETURN;
}

void Item_in_subselect::select_transformer(st_select_lex *select_lex)
{
  single_value_transformer(select_lex, left_expr,
			   &Item_bool_func2::eq_creator);
}

void Item_allany_subselect::select_transformer(st_select_lex *select_lex)
{
  single_value_transformer(select_lex, left_expr, func);
}

subselect_single_select_engine::subselect_single_select_engine(THD *thd, 
							       st_select_lex *select,
							       select_subselect *result,
							       Item_subselect *item):
  subselect_engine(thd, item, result),
    prepared(0), optimized(0), executed(0)
{
  select_lex= select;
  SELECT_LEX_UNIT *unit= select_lex->master_unit();
  unit->offset_limit_cnt= unit->global_parameters->offset_limit;
  unit->select_limit_cnt= unit->global_parameters->select_limit+
    unit->global_parameters ->offset_limit;
  if (unit->select_limit_cnt < unit->global_parameters->select_limit)
    unit->select_limit_cnt= HA_POS_ERROR;		// no limit
  if (unit->select_limit_cnt == HA_POS_ERROR)
    select_lex->options&= ~OPTION_FOUND_ROWS;
  join= new JOIN(thd, select_lex->item_list, select_lex->options, result);
  if (!join || !result)
  {
    //out of memory
    thd->fatal_error= 1;
    my_message(ER_OUT_OF_RESOURCES, ER(ER_OUT_OF_RESOURCES), MYF(0));
  } 
  unit->item= item;
  this->select_lex= select_lex;
}

subselect_union_engine::subselect_union_engine(THD *thd,
					       st_select_lex_unit *u,
					       select_subselect *result,
					       Item_subselect *item):
  subselect_engine(thd, item, result)
{
  unit= u;
  if( !result)
  {
    //out of memory
    thd->fatal_error= 1;
    my_message(ER_OUT_OF_RESOURCES, ER(ER_OUT_OF_RESOURCES), MYF(0));
  }
  unit->item= item;
}

int subselect_single_select_engine::prepare()
{
  if (prepared)
    return 0;
  prepared= 1;
  SELECT_LEX_NODE *save_select= thd->lex.current_select;
  thd->lex.current_select= select_lex;
  if(join->prepare((TABLE_LIST*) select_lex->table_list.first,
		   select_lex->where,
		   (ORDER*) select_lex->order_list.first,
		   (ORDER*) select_lex->group_list.first,
		   select_lex->having,
		   (ORDER*) 0, select_lex, 
		   select_lex->master_unit(), 0))
    return 1;
  thd->lex.current_select= save_select;
  return 0;
}

int subselect_union_engine::prepare()
{
  return unit->prepare(thd, result);
}

void subselect_single_select_engine::fix_length_and_dec()
{
  List_iterator_fast<Item> li(select_lex->item_list);
  Item *sel_item= li++;
  item->max_length= sel_item->max_length;
  res_type= sel_item->result_type();
  item->decimals= sel_item->decimals;
}

void subselect_union_engine::fix_length_and_dec()
{
  uint32 mlen= 0, len;
  Item *sel_item= 0;
  for (SELECT_LEX *sl= unit->first_select(); sl; sl= sl->next_select())
  {
    List_iterator_fast<Item> li(sl->item_list);
    Item *s_item= li++;
    if ((len= s_item->max_length))
      mlen= len;
    if (!sel_item)
      sel_item= s_item;
  }
  item->max_length= mlen;
  res_type= sel_item->result_type();
  item->decimals= sel_item->decimals;
}

int subselect_single_select_engine::exec()
{
  DBUG_ENTER("subselect_single_select_engine::exec");
  char const *save_where= join->thd->where;
  if (!optimized)
  {
    optimized=1;
    if (join->optimize())
    {
      join->thd->where= save_where;
      executed= 1;
      DBUG_RETURN(join->error?join->error:1);
    }
  }
  if (select_lex->dependent && executed)
  {
    if (join->reinit())
    {
      join->thd->where= save_where;
      DBUG_RETURN(1);
    }
    item->assign_null();
    item->assigned((executed= 0));
  }
  if (!executed)
  {
    SELECT_LEX_NODE *save_select= join->thd->lex.current_select;
    join->thd->lex.current_select= select_lex;
    join->exec();
    join->thd->lex.current_select= save_select;
    executed= 1;
    join->thd->where= save_where;
    DBUG_RETURN(join->error||thd->fatal_error);
  }
  join->thd->where= save_where;
  DBUG_RETURN(0);
}

int subselect_union_engine::exec()
{
  char const *save_where= unit->thd->where;
  int res= unit->exec();
  unit->thd->where= save_where;
  return res;
}

uint subselect_single_select_engine::cols()
{
  return select_lex->item_list.elements;
}

uint subselect_union_engine::cols()
{
  return unit->first_select()->item_list.elements;
}

bool subselect_single_select_engine::depended()
{
  return select_lex->dependent;
}

bool subselect_union_engine::depended()
{
  return unit->dependent;
}

bool subselect_single_select_engine::check_loop(uint id)
{
  DBUG_ENTER("subselect_single_select_engine::check_loop");
  DBUG_RETURN(join->check_loop(id));
}

bool subselect_union_engine::check_loop(uint id)
{
  DBUG_ENTER("subselect_union_engine::check_loop");
  for (SELECT_LEX *sl= unit->first_select(); sl; sl= sl->next_select())
    if (sl->join && sl->join->check_loop(id))
      DBUG_RETURN(1);
  DBUG_RETURN(0);
}

void subselect_single_select_engine::exclude()
{
  select_lex->master_unit()->exclude_level();
  //if (current_thd->lex->describe)
}

void subselect_union_engine::exclude()
{
  unit->exclude_level();
  // for (SELECT_LEX *sl= unit->first_select(); sl; sl= sl->next_select())
  //  if (sl->join && sl->join->check_loop(id))
  //    DBUG_RETURN(1);
}