1<?php 2/** 3 * CDbSchema class file. 4 * 5 * @author Qiang Xue <qiang.xue@gmail.com> 6 * @link http://www.yiiframework.com/ 7 * @copyright 2008-2013 Yii Software LLC 8 * @license http://www.yiiframework.com/license/ 9 */ 10 11/** 12 * CDbSchema is the base class for retrieving metadata information. 13 * 14 * @property CDbConnection $dbConnection Database connection. The connection is active. 15 * @property array $tables The metadata for all tables in the database. 16 * Each array element is an instance of {@link CDbTableSchema} (or its child class). 17 * The array keys are table names. 18 * @property array $tableNames All table names in the database. 19 * @property CDbCommandBuilder $commandBuilder The SQL command builder for this connection. 20 * 21 * @author Qiang Xue <qiang.xue@gmail.com> 22 * @package system.db.schema 23 * @since 1.0 24 */ 25abstract class CDbSchema extends CComponent 26{ 27 /** 28 * @var array the abstract column types mapped to physical column types. 29 * @since 1.1.6 30 */ 31 public $columnTypes=array(); 32 33 private $_tableNames=array(); 34 private $_tables=array(); 35 private $_connection; 36 private $_builder; 37 private $_cacheExclude=array(); 38 39 /** 40 * Loads the metadata for the specified table. 41 * @param string $name table name 42 * @return CDbTableSchema driver dependent table metadata, null if the table does not exist. 43 */ 44 abstract protected function loadTable($name); 45 46 /** 47 * Constructor. 48 * @param CDbConnection $conn database connection. 49 */ 50 public function __construct($conn) 51 { 52 $this->_connection=$conn; 53 foreach($conn->schemaCachingExclude as $name) 54 $this->_cacheExclude[$name]=true; 55 } 56 57 /** 58 * @return CDbConnection database connection. The connection is active. 59 */ 60 public function getDbConnection() 61 { 62 return $this->_connection; 63 } 64 65 /** 66 * Obtains the metadata for the named table. 67 * @param string $name table name 68 * @param boolean $refresh if we need to refresh schema cache for a table. 69 * Parameter available since 1.1.9 70 * @return CDbTableSchema table metadata. Null if the named table does not exist. 71 */ 72 public function getTable($name,$refresh=false) 73 { 74 if($refresh===false && isset($this->_tables[$name])) 75 return $this->_tables[$name]; 76 else 77 { 78 if($this->_connection->tablePrefix!==null && strpos($name,'{{')!==false) 79 $realName=preg_replace('/\{\{(.*?)\}\}/',$this->_connection->tablePrefix.'$1',$name); 80 else 81 $realName=$name; 82 83 // temporarily disable query caching 84 if($this->_connection->queryCachingDuration>0) 85 { 86 $qcDuration=$this->_connection->queryCachingDuration; 87 $this->_connection->queryCachingDuration=0; 88 } 89 90 if(!isset($this->_cacheExclude[$name]) && ($duration=$this->_connection->schemaCachingDuration)>0 && $this->_connection->schemaCacheID!==false && ($cache=Yii::app()->getComponent($this->_connection->schemaCacheID))!==null) 91 { 92 $key='yii:dbschema'.$this->_connection->connectionString.':'.$this->_connection->username.':'.$name; 93 $table=$cache->get($key); 94 if($refresh===true || $table===false) 95 { 96 $table=$this->loadTable($realName); 97 if($table!==null) 98 $cache->set($key,$table,$duration); 99 } 100 $this->_tables[$name]=$table; 101 } 102 else 103 $this->_tables[$name]=$table=$this->loadTable($realName); 104 105 if(isset($qcDuration)) // re-enable query caching 106 $this->_connection->queryCachingDuration=$qcDuration; 107 108 return $table; 109 } 110 } 111 112 /** 113 * Returns the metadata for all tables in the database. 114 * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema. 115 * @return array the metadata for all tables in the database. 116 * Each array element is an instance of {@link CDbTableSchema} (or its child class). 117 * The array keys are table names. 118 */ 119 public function getTables($schema='') 120 { 121 $tables=array(); 122 foreach($this->getTableNames($schema) as $name) 123 { 124 if(($table=$this->getTable($name))!==null) 125 $tables[$name]=$table; 126 } 127 return $tables; 128 } 129 130 /** 131 * Returns all table names in the database. 132 * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema. 133 * If not empty, the returned table names will be prefixed with the schema name. 134 * @return array all table names in the database. 135 */ 136 public function getTableNames($schema='') 137 { 138 if(!isset($this->_tableNames[$schema])) 139 $this->_tableNames[$schema]=$this->findTableNames($schema); 140 return $this->_tableNames[$schema]; 141 } 142 143 /** 144 * @return CDbCommandBuilder the SQL command builder for this connection. 145 */ 146 public function getCommandBuilder() 147 { 148 if($this->_builder!==null) 149 return $this->_builder; 150 else 151 return $this->_builder=$this->createCommandBuilder(); 152 } 153 154 /** 155 * Refreshes the schema. 156 * This method resets the loaded table metadata and command builder 157 * so that they can be recreated to reflect the change of schema. 158 */ 159 public function refresh() 160 { 161 if(($duration=$this->_connection->schemaCachingDuration)>0 && $this->_connection->schemaCacheID!==false && ($cache=Yii::app()->getComponent($this->_connection->schemaCacheID))!==null) 162 { 163 foreach(array_keys($this->_tables) as $name) 164 { 165 if(!isset($this->_cacheExclude[$name])) 166 { 167 $key='yii:dbschema'.$this->_connection->connectionString.':'.$this->_connection->username.':'.$name; 168 $cache->delete($key); 169 } 170 } 171 } 172 $this->_tables=array(); 173 $this->_tableNames=array(); 174 $this->_builder=null; 175 } 176 177 /** 178 * Quotes a table name for use in a query. 179 * If the table name contains schema prefix, the prefix will also be properly quoted. 180 * @param string $name table name 181 * @return string the properly quoted table name 182 * @see quoteSimpleTableName 183 */ 184 public function quoteTableName($name) 185 { 186 if(strpos($name,'.')===false) 187 return $this->quoteSimpleTableName($name); 188 $parts=explode('.',$name); 189 foreach($parts as $i=>$part) 190 $parts[$i]=$this->quoteSimpleTableName($part); 191 return implode('.',$parts); 192 193 } 194 195 /** 196 * Quotes a simple table name for use in a query. 197 * A simple table name does not schema prefix. 198 * @param string $name table name 199 * @return string the properly quoted table name 200 * @since 1.1.6 201 */ 202 public function quoteSimpleTableName($name) 203 { 204 return "'".$name."'"; 205 } 206 207 /** 208 * Quotes a column name for use in a query. 209 * If the column name contains prefix, the prefix will also be properly quoted. 210 * @param string $name column name 211 * @return string the properly quoted column name 212 * @see quoteSimpleColumnName 213 */ 214 public function quoteColumnName($name) 215 { 216 if(($pos=strrpos($name,'.'))!==false) 217 { 218 $prefix=$this->quoteTableName(substr($name,0,$pos)).'.'; 219 $name=substr($name,$pos+1); 220 } 221 else 222 $prefix=''; 223 return $prefix . ($name==='*' ? $name : $this->quoteSimpleColumnName($name)); 224 } 225 226 /** 227 * Quotes a simple column name for use in a query. 228 * A simple column name does not contain prefix. 229 * @param string $name column name 230 * @return string the properly quoted column name 231 * @since 1.1.6 232 */ 233 public function quoteSimpleColumnName($name) 234 { 235 return '"'.$name.'"'; 236 } 237 238 /** 239 * Compares two table names. 240 * The table names can be either quoted or unquoted. This method 241 * will consider both cases. 242 * @param string $name1 table name 1 243 * @param string $name2 table name 2 244 * @return boolean whether the two table names refer to the same table. 245 */ 246 public function compareTableNames($name1,$name2) 247 { 248 $name1=str_replace(array('"','`',"'"),'',$name1); 249 $name2=str_replace(array('"','`',"'"),'',$name2); 250 if(($pos=strrpos($name1,'.'))!==false) 251 $name1=substr($name1,$pos+1); 252 if(($pos=strrpos($name2,'.'))!==false) 253 $name2=substr($name2,$pos+1); 254 if($this->_connection->tablePrefix!==null) 255 { 256 if(strpos($name1,'{')!==false) 257 $name1=$this->_connection->tablePrefix.str_replace(array('{','}'),'',$name1); 258 if(strpos($name2,'{')!==false) 259 $name2=$this->_connection->tablePrefix.str_replace(array('{','}'),'',$name2); 260 } 261 return $name1===$name2; 262 } 263 264 /** 265 * Resets the sequence value of a table's primary key. 266 * The sequence will be reset such that the primary key of the next new row inserted 267 * will have the specified value or max value of a primary key plus one (i.e. sequence trimming). 268 * @param CDbTableSchema $table the table schema whose primary key sequence will be reset 269 * @param integer|null $value the value for the primary key of the next new row inserted. 270 * If this is not set, the next new row's primary key will have the max value of a primary 271 * key plus one (i.e. sequence trimming). 272 * @since 1.1 273 */ 274 public function resetSequence($table,$value=null) 275 { 276 } 277 278 /** 279 * Enables or disables integrity check. 280 * @param boolean $check whether to turn on or off the integrity check. 281 * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema. 282 * @since 1.1 283 */ 284 public function checkIntegrity($check=true,$schema='') 285 { 286 } 287 288 /** 289 * Creates a command builder for the database. 290 * This method may be overridden by child classes to create a DBMS-specific command builder. 291 * @return CDbCommandBuilder command builder instance 292 */ 293 protected function createCommandBuilder() 294 { 295 return new CDbCommandBuilder($this); 296 } 297 298 /** 299 * Returns all table names in the database. 300 * This method should be overridden by child classes in order to support this feature 301 * because the default implementation simply throws an exception. 302 * @param string $schema the schema of the tables. Defaults to empty string, meaning the current or default schema. 303 * If not empty, the returned table names will be prefixed with the schema name. 304 * @throws CDbException if current schema does not support fetching all table names 305 * @return array all table names in the database. 306 */ 307 protected function findTableNames($schema='') 308 { 309 throw new CDbException(Yii::t('yii','{class} does not support fetching all table names.', 310 array('{class}'=>get_class($this)))); 311 } 312 313 /** 314 * Converts an abstract column type into a physical column type. 315 * The conversion is done using the type map specified in {@link columnTypes}. 316 * These abstract column types are supported (using MySQL as example to explain the corresponding 317 * physical types): 318 * <ul> 319 * <li>pk and bigpk: an auto-incremental primary key type, will be converted into "int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY" or "bigint(20) NOT NULL AUTO_INCREMENT PRIMARY KEY"</li> 320 * <li>string: string type, will be converted into "varchar(255)"</li> 321 * <li>text: a long string type, will be converted into "text"</li> 322 * <li>integer: integer type, will be converted into "int(11)"</li> 323 * <li>bigint: integer type, will be converted into "bigint(20)"</li> 324 * <li>boolean: boolean type, will be converted into "tinyint(1)"</li> 325 * <li>float: float number type, will be converted into "float"</li> 326 * <li>decimal: decimal number type, will be converted into "decimal"</li> 327 * <li>datetime: datetime type, will be converted into "datetime"</li> 328 * <li>timestamp: timestamp type, will be converted into "timestamp"</li> 329 * <li>time: time type, will be converted into "time"</li> 330 * <li>date: date type, will be converted into "date"</li> 331 * <li>binary: binary data type, will be converted into "blob"</li> 332 * </ul> 333 * 334 * If the abstract type contains two or more parts separated by spaces (e.g. "string NOT NULL"), then only 335 * the first part will be converted, and the rest of the parts will be appended to the conversion result. 336 * For example, 'string NOT NULL' is converted to 'varchar(255) NOT NULL'. 337 * @param string $type abstract column type 338 * @return string physical column type. 339 * @since 1.1.6 340 */ 341 public function getColumnType($type) 342 { 343 if(isset($this->columnTypes[$type])) 344 return $this->columnTypes[$type]; 345 elseif(($pos=strpos($type,' '))!==false) 346 { 347 $t=substr($type,0,$pos); 348 return (isset($this->columnTypes[$t]) ? $this->columnTypes[$t] : $t).substr($type,$pos); 349 } 350 else 351 return $type; 352 } 353 354 /** 355 * Builds a SQL statement for creating a new DB table. 356 * 357 * The columns in the new table should be specified as name-definition pairs (e.g. 'name'=>'string'), 358 * where name stands for a column name which will be properly quoted by the method, and definition 359 * stands for the column type which can contain an abstract DB type. 360 * The {@link getColumnType} method will be invoked to convert any abstract type into a physical one. 361 * 362 * If a column is specified with definition only (e.g. 'PRIMARY KEY (name, type)'), it will be directly 363 * inserted into the generated SQL. 364 * 365 * @param string $table the name of the table to be created. The name will be properly quoted by the method. 366 * @param array $columns the columns (name=>definition) in the new table. 367 * @param string $options additional SQL fragment that will be appended to the generated SQL. 368 * @return string the SQL statement for creating a new DB table. 369 * @since 1.1.6 370 */ 371 public function createTable($table,$columns,$options=null) 372 { 373 $cols=array(); 374 foreach($columns as $name=>$type) 375 { 376 if(is_string($name)) 377 $cols[]="\t".$this->quoteColumnName($name).' '.$this->getColumnType($type); 378 else 379 $cols[]="\t".$type; 380 } 381 $sql="CREATE TABLE ".$this->quoteTableName($table)." (\n".implode(",\n",$cols)."\n)"; 382 return $options===null ? $sql : $sql.' '.$options; 383 } 384 385 /** 386 * Builds a SQL statement for renaming a DB table. 387 * @param string $table the table to be renamed. The name will be properly quoted by the method. 388 * @param string $newName the new table name. The name will be properly quoted by the method. 389 * @return string the SQL statement for renaming a DB table. 390 * @since 1.1.6 391 */ 392 public function renameTable($table,$newName) 393 { 394 return 'RENAME TABLE ' . $this->quoteTableName($table) . ' TO ' . $this->quoteTableName($newName); 395 } 396 397 /** 398 * Builds a SQL statement for dropping a DB table. 399 * @param string $table the table to be dropped. The name will be properly quoted by the method. 400 * @return string the SQL statement for dropping a DB table. 401 * @since 1.1.6 402 */ 403 public function dropTable($table) 404 { 405 return "DROP TABLE ".$this->quoteTableName($table); 406 } 407 408 /** 409 * Builds a SQL statement for truncating a DB table. 410 * @param string $table the table to be truncated. The name will be properly quoted by the method. 411 * @return string the SQL statement for truncating a DB table. 412 * @since 1.1.6 413 */ 414 public function truncateTable($table) 415 { 416 return "TRUNCATE TABLE ".$this->quoteTableName($table); 417 } 418 419 /** 420 * Builds a SQL statement for adding a new DB column. 421 * @param string $table the table that the new column will be added to. The table name will be properly quoted by the method. 422 * @param string $column the name of the new column. The name will be properly quoted by the method. 423 * @param string $type the column type. The {@link getColumnType} method will be invoked to convert abstract column type (if any) 424 * into the physical one. Anything that is not recognized as abstract type will be kept in the generated SQL. 425 * For example, 'string' will be turned into 'varchar(255)', while 'string not null' will become 'varchar(255) not null'. 426 * @return string the SQL statement for adding a new column. 427 * @since 1.1.6 428 */ 429 public function addColumn($table,$column,$type) 430 { 431 return 'ALTER TABLE ' . $this->quoteTableName($table) 432 . ' ADD ' . $this->quoteColumnName($column) . ' ' 433 . $this->getColumnType($type); 434 } 435 436 /** 437 * Builds a SQL statement for dropping a DB column. 438 * @param string $table the table whose column is to be dropped. The name will be properly quoted by the method. 439 * @param string $column the name of the column to be dropped. The name will be properly quoted by the method. 440 * @return string the SQL statement for dropping a DB column. 441 * @since 1.1.6 442 */ 443 public function dropColumn($table,$column) 444 { 445 return "ALTER TABLE ".$this->quoteTableName($table) 446 ." DROP COLUMN ".$this->quoteColumnName($column); 447 } 448 449 /** 450 * Builds a SQL statement for renaming a column. 451 * @param string $table the table whose column is to be renamed. The name will be properly quoted by the method. 452 * @param string $name the old name of the column. The name will be properly quoted by the method. 453 * @param string $newName the new name of the column. The name will be properly quoted by the method. 454 * @return string the SQL statement for renaming a DB column. 455 * @since 1.1.6 456 */ 457 public function renameColumn($table,$name,$newName) 458 { 459 return "ALTER TABLE ".$this->quoteTableName($table) 460 . " RENAME COLUMN ".$this->quoteColumnName($name) 461 . " TO ".$this->quoteColumnName($newName); 462 } 463 464 /** 465 * Builds a SQL statement for changing the definition of a column. 466 * @param string $table the table whose column is to be changed. The table name will be properly quoted by the method. 467 * @param string $column the name of the column to be changed. The name will be properly quoted by the method. 468 * @param string $type the new column type. The {@link getColumnType} method will be invoked to convert abstract column type (if any) 469 * into the physical one. Anything that is not recognized as abstract type will be kept in the generated SQL. 470 * For example, 'string' will be turned into 'varchar(255)', while 'string not null' will become 'varchar(255) not null'. 471 * @return string the SQL statement for changing the definition of a column. 472 * @since 1.1.6 473 */ 474 public function alterColumn($table,$column,$type) 475 { 476 return 'ALTER TABLE ' . $this->quoteTableName($table) . ' CHANGE ' 477 . $this->quoteColumnName($column) . ' ' 478 . $this->quoteColumnName($column) . ' ' 479 . $this->getColumnType($type); 480 } 481 482 /** 483 * Builds a SQL statement for adding a foreign key constraint to an existing table. 484 * The method will properly quote the table and column names. 485 * @param string $name the name of the foreign key constraint. 486 * @param string $table the table that the foreign key constraint will be added to. 487 * @param string|array $columns the name of the column to that the constraint will be added on. If there are multiple columns, separate them with commas or pass as an array of column names. 488 * @param string $refTable the table that the foreign key references to. 489 * @param string|array $refColumns the name of the column that the foreign key references to. If there are multiple columns, separate them with commas or pass as an array of column names. 490 * @param string $delete the ON DELETE option. Most DBMS support these options: RESTRICT, CASCADE, NO ACTION, SET DEFAULT, SET NULL 491 * @param string $update the ON UPDATE option. Most DBMS support these options: RESTRICT, CASCADE, NO ACTION, SET DEFAULT, SET NULL 492 * @return string the SQL statement for adding a foreign key constraint to an existing table. 493 * @since 1.1.6 494 */ 495 public function addForeignKey($name,$table,$columns,$refTable,$refColumns,$delete=null,$update=null) 496 { 497 if(is_string($columns)) 498 $columns=preg_split('/\s*,\s*/',$columns,-1,PREG_SPLIT_NO_EMPTY); 499 foreach($columns as $i=>$col) 500 $columns[$i]=$this->quoteColumnName($col); 501 if(is_string($refColumns)) 502 $refColumns=preg_split('/\s*,\s*/',$refColumns,-1,PREG_SPLIT_NO_EMPTY); 503 foreach($refColumns as $i=>$col) 504 $refColumns[$i]=$this->quoteColumnName($col); 505 $sql='ALTER TABLE '.$this->quoteTableName($table) 506 .' ADD CONSTRAINT '.$this->quoteColumnName($name) 507 .' FOREIGN KEY ('.implode(', ',$columns).')' 508 .' REFERENCES '.$this->quoteTableName($refTable) 509 .' ('.implode(', ',$refColumns).')'; 510 if($delete!==null) 511 $sql.=' ON DELETE '.$delete; 512 if($update!==null) 513 $sql.=' ON UPDATE '.$update; 514 return $sql; 515 } 516 517 /** 518 * Builds a SQL statement for dropping a foreign key constraint. 519 * @param string $name the name of the foreign key constraint to be dropped. The name will be properly quoted by the method. 520 * @param string $table the table whose foreign is to be dropped. The name will be properly quoted by the method. 521 * @return string the SQL statement for dropping a foreign key constraint. 522 * @since 1.1.6 523 */ 524 public function dropForeignKey($name,$table) 525 { 526 return 'ALTER TABLE '.$this->quoteTableName($table) 527 .' DROP CONSTRAINT '.$this->quoteColumnName($name); 528 } 529 530 /** 531 * Builds a SQL statement for creating a new index. 532 * @param string $name the name of the index. The name will be properly quoted by the method. 533 * @param string $table the table that the new index will be created for. The table name will be properly quoted by the method. 534 * @param string|array $columns the column(s) that should be included in the index. If there are multiple columns, please separate them 535 * by commas or pass as an array of column names. Each column name will be properly quoted by the method, unless a parenthesis is found in the name. 536 * @param boolean $unique whether to add UNIQUE constraint on the created index. 537 * @return string the SQL statement for creating a new index. 538 * @since 1.1.6 539 */ 540 public function createIndex($name,$table,$columns,$unique=false) 541 { 542 $cols=array(); 543 if(is_string($columns)) 544 $columns=preg_split('/\s*,\s*/',$columns,-1,PREG_SPLIT_NO_EMPTY); 545 foreach($columns as $col) 546 { 547 if(strpos($col,'(')!==false) 548 $cols[]=$col; 549 else 550 $cols[]=$this->quoteColumnName($col); 551 } 552 return ($unique ? 'CREATE UNIQUE INDEX ' : 'CREATE INDEX ') 553 . $this->quoteTableName($name).' ON ' 554 . $this->quoteTableName($table).' ('.implode(', ',$cols).')'; 555 } 556 557 /** 558 * Builds a SQL statement for dropping an index. 559 * @param string $name the name of the index to be dropped. The name will be properly quoted by the method. 560 * @param string $table the table whose index is to be dropped. The name will be properly quoted by the method. 561 * @return string the SQL statement for dropping an index. 562 * @since 1.1.6 563 */ 564 public function dropIndex($name,$table) 565 { 566 return 'DROP INDEX '.$this->quoteTableName($name).' ON '.$this->quoteTableName($table); 567 } 568 569 /** 570 * Builds a SQL statement for adding a primary key constraint to an existing table. 571 * @param string $name the name of the primary key constraint. 572 * @param string $table the table that the primary key constraint will be added to. 573 * @param string|array $columns comma separated string or array of columns that the primary key will consist of. 574 * Array value can be passed since 1.1.14. 575 * @return string the SQL statement for adding a primary key constraint to an existing table. 576 * @since 1.1.13 577 */ 578 public function addPrimaryKey($name,$table,$columns) 579 { 580 if(is_string($columns)) 581 $columns=preg_split('/\s*,\s*/',$columns,-1,PREG_SPLIT_NO_EMPTY); 582 foreach($columns as $i=>$col) 583 $columns[$i]=$this->quoteColumnName($col); 584 return 'ALTER TABLE ' . $this->quoteTableName($table) . ' ADD CONSTRAINT ' 585 . $this->quoteColumnName($name) . ' PRIMARY KEY (' 586 . implode(', ',$columns). ' )'; 587 } 588 589 /** 590 * Builds a SQL statement for removing a primary key constraint to an existing table. 591 * @param string $name the name of the primary key constraint to be removed. 592 * @param string $table the table that the primary key constraint will be removed from. 593 * @return string the SQL statement for removing a primary key constraint from an existing table. 594 * @since 1.1.13 595 */ 596 public function dropPrimaryKey($name,$table) 597 { 598 return 'ALTER TABLE ' . $this->quoteTableName($table) . ' DROP CONSTRAINT ' 599 . $this->quoteColumnName($name); 600 } 601} 602