Complex classes like Schema often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Schema, and based on these observations, apply Extract Interface, too.
1 | <?php |
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33 | class Schema extends \yii\db\Schema implements ConstraintFinderInterface |
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34 | { |
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35 | use ConstraintFinderTrait; |
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36 | |||
37 | /** |
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38 | * @var array mapping from physical column types (keys) to abstract column types (values) |
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39 | */ |
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40 | public $typeMap = [ |
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41 | 'tinyint' => self::TYPE_TINYINT, |
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42 | 'bit' => self::TYPE_SMALLINT, |
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43 | 'boolean' => self::TYPE_BOOLEAN, |
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44 | 'bool' => self::TYPE_BOOLEAN, |
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45 | 'smallint' => self::TYPE_SMALLINT, |
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46 | 'mediumint' => self::TYPE_INTEGER, |
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47 | 'int' => self::TYPE_INTEGER, |
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48 | 'integer' => self::TYPE_INTEGER, |
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49 | 'bigint' => self::TYPE_BIGINT, |
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50 | 'float' => self::TYPE_FLOAT, |
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51 | 'double' => self::TYPE_DOUBLE, |
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52 | 'real' => self::TYPE_FLOAT, |
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53 | 'decimal' => self::TYPE_DECIMAL, |
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54 | 'numeric' => self::TYPE_DECIMAL, |
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55 | 'tinytext' => self::TYPE_TEXT, |
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56 | 'mediumtext' => self::TYPE_TEXT, |
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57 | 'longtext' => self::TYPE_TEXT, |
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58 | 'text' => self::TYPE_TEXT, |
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59 | 'varchar' => self::TYPE_STRING, |
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60 | 'string' => self::TYPE_STRING, |
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61 | 'char' => self::TYPE_CHAR, |
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62 | 'blob' => self::TYPE_BINARY, |
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63 | 'datetime' => self::TYPE_DATETIME, |
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64 | 'year' => self::TYPE_DATE, |
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65 | 'date' => self::TYPE_DATE, |
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66 | 'time' => self::TYPE_TIME, |
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67 | 'timestamp' => self::TYPE_TIMESTAMP, |
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68 | 'enum' => self::TYPE_STRING, |
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69 | ]; |
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70 | |||
71 | /** |
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72 | * {@inheritdoc} |
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73 | */ |
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74 | protected $tableQuoteCharacter = '`'; |
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75 | /** |
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76 | * {@inheritdoc} |
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77 | */ |
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78 | protected $columnQuoteCharacter = '`'; |
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79 | |||
80 | |||
81 | /** |
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82 | * {@inheritdoc} |
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83 | */ |
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84 | 6 | protected function findTableNames($schema = '') |
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89 | |||
90 | /** |
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91 | * {@inheritdoc} |
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92 | */ |
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93 | 293 | protected function loadTableSchema($name) |
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106 | |||
107 | /** |
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108 | * {@inheritdoc} |
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109 | */ |
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110 | 37 | protected function loadTablePrimaryKey($tableName) |
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114 | |||
115 | /** |
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116 | * {@inheritdoc} |
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117 | */ |
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118 | 3 | protected function loadTableForeignKeys($tableName) |
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137 | |||
138 | /** |
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139 | * {@inheritdoc} |
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140 | */ |
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141 | 10 | protected function loadTableIndexes($tableName) |
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145 | |||
146 | /** |
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147 | * {@inheritdoc} |
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148 | */ |
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149 | 12 | protected function loadTableUniques($tableName) |
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153 | |||
154 | /** |
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155 | * {@inheritdoc} |
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156 | */ |
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157 | 12 | protected function loadTableChecks($tableName) |
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192 | |||
193 | /** |
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194 | * {@inheritdoc} |
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195 | * @throws NotSupportedException if this method is called. |
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196 | */ |
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197 | 12 | protected function loadTableDefaultValues($tableName) |
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201 | |||
202 | /** |
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203 | * Creates a query builder for the MySQL database. |
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204 | * This method may be overridden by child classes to create a DBMS-specific query builder. |
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205 | * @return QueryBuilder query builder instance |
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206 | */ |
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207 | 270 | public function createQueryBuilder() |
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211 | |||
212 | /** |
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213 | * {@inheritdoc} |
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214 | * @return ColumnSchemaBuilder column schema builder instance |
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215 | */ |
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216 | 10 | public function createColumnSchemaBuilder($type, $length = null) |
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220 | |||
221 | /** |
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222 | * Collects the table column metadata. |
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223 | * @param TableSchema $table the table metadata |
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224 | * @return bool whether the table exists in the database |
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225 | */ |
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226 | 293 | protected function findColumns($table) |
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248 | |||
249 | /** |
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250 | * Collects the foreign key column details for the given table. |
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251 | * @param TableSchema $table the table metadata |
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252 | */ |
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253 | 271 | protected function findConstraints($table) |
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267 | |||
268 | /** |
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269 | * Returns all unique indexes for the given table. |
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270 | * |
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271 | * Each array element is of the following structure: |
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272 | * |
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273 | * ```php |
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274 | * [ |
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275 | * 'IndexName1' => ['col1' [, ...]], |
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276 | * 'IndexName2' => ['col2' [, ...]], |
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277 | * ] |
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278 | * ``` |
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279 | * |
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280 | * @param TableSchema $table the table metadata |
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281 | * @return array all unique indexes for the given table. |
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282 | */ |
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283 | 1 | public function findUniqueIndexes($table) |
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303 | |||
304 | /** |
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305 | * Loads the column information into a [[ColumnSchema]] object. |
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306 | * @param array $info column information |
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307 | * @return ColumnSchema the column schema object |
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308 | */ |
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309 | 271 | protected function loadColumnSchema($info) |
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358 | |||
359 | /** |
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360 | * Sets the isolation level of the current transaction. |
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361 | * @param string $level The transaction isolation level to use for this transaction. |
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362 | * This can be either [[Transaction::READ_UNCOMMITTED]] or [[Transaction::SERIALIZABLE]]. |
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363 | * @throws NotSupportedException when unsupported isolation levels are used. |
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364 | * SQLite only supports SERIALIZABLE and READ UNCOMMITTED. |
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365 | * @see http://www.sqlite.org/pragma.html#pragma_read_uncommitted |
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366 | */ |
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367 | 2 | public function setTransactionIsolationLevel($level) |
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380 | |||
381 | /** |
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382 | * Returns table columns info. |
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383 | * @param string $tableName table name |
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384 | * @return array |
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385 | */ |
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386 | 30 | private function loadTableColumnsInfo($tableName) |
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393 | |||
394 | /** |
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395 | * Loads multiple types of constraints and returns the specified ones. |
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396 | * @param string $tableName table name. |
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397 | * @param string $returnType return type: |
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398 | * - primaryKey |
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399 | * - indexes |
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400 | * - uniques |
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401 | * @return mixed constraints. |
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402 | */ |
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403 | 59 | private function loadTableConstraints($tableName, $returnType) |
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475 | |||
476 | /** |
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477 | * Return whether the specified identifier is a SQLite system identifier. |
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478 | * @param string $identifier |
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479 | * @return bool |
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480 | * @see https://www.sqlite.org/src/artifact/74108007d286232f |
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481 | */ |
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482 | private function isSystemIdentifier($identifier) |
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486 | } |
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487 |
If a method or function can return multiple different values and unless you are sure that you only can receive a single value in this context, we recommend to add an additional type check:
If this a common case that PHP Analyzer should handle natively, please let us know by opening an issue.