Complex classes like QueryBuilder 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 QueryBuilder, and based on these observations, apply Extract Interface, too.
1 | <?php |
||
21 | class QueryBuilder extends \yii\db\QueryBuilder |
||
22 | { |
||
23 | /** |
||
24 | * @var array mapping from abstract column types (keys) to physical column types (values). |
||
25 | */ |
||
26 | public $typeMap = [ |
||
27 | Schema::TYPE_PK => 'int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
28 | Schema::TYPE_UPK => 'int(10) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
29 | Schema::TYPE_BIGPK => 'bigint(20) NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
30 | Schema::TYPE_UBIGPK => 'bigint(20) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
31 | Schema::TYPE_CHAR => 'char(1)', |
||
32 | Schema::TYPE_STRING => 'varchar(255)', |
||
33 | Schema::TYPE_TEXT => 'text', |
||
34 | Schema::TYPE_SMALLINT => 'smallint(6)', |
||
35 | Schema::TYPE_INTEGER => 'int(11)', |
||
36 | Schema::TYPE_BIGINT => 'bigint(20)', |
||
37 | Schema::TYPE_FLOAT => 'float', |
||
38 | Schema::TYPE_DOUBLE => 'double', |
||
39 | Schema::TYPE_DECIMAL => 'decimal(10,0)', |
||
40 | Schema::TYPE_DATETIME => 'datetime', |
||
41 | Schema::TYPE_TIMESTAMP => 'timestamp', |
||
42 | Schema::TYPE_TIME => 'time', |
||
43 | Schema::TYPE_DATE => 'date', |
||
44 | Schema::TYPE_BINARY => 'blob', |
||
45 | Schema::TYPE_BOOLEAN => 'tinyint(1)', |
||
46 | Schema::TYPE_MONEY => 'decimal(19,4)', |
||
47 | ]; |
||
48 | |||
49 | |||
50 | /** |
||
51 | * Builds a SQL statement for renaming a column. |
||
52 | * @param string $table the table whose column is to be renamed. The name will be properly quoted by the method. |
||
53 | * @param string $oldName the old name of the column. The name will be properly quoted by the method. |
||
54 | * @param string $newName the new name of the column. The name will be properly quoted by the method. |
||
55 | * @return string the SQL statement for renaming a DB column. |
||
56 | * @throws Exception |
||
57 | */ |
||
58 | public function renameColumn($table, $oldName, $newName) |
||
59 | { |
||
60 | $quotedTable = $this->db->quoteTableName($table); |
||
61 | $row = $this->db->createCommand('SHOW CREATE TABLE ' . $quotedTable)->queryOne(); |
||
62 | if ($row === false) { |
||
63 | throw new Exception("Unable to find column '$oldName' in table '$table'."); |
||
64 | } |
||
65 | if (isset($row['Create Table'])) { |
||
66 | $sql = $row['Create Table']; |
||
67 | } else { |
||
68 | $row = array_values($row); |
||
69 | $sql = $row[1]; |
||
70 | } |
||
71 | if (preg_match_all('/^\s*`(.*?)`\s+(.*?),?$/m', $sql, $matches)) { |
||
72 | foreach ($matches[1] as $i => $c) { |
||
73 | if ($c === $oldName) { |
||
74 | return "ALTER TABLE $quotedTable CHANGE " |
||
75 | . $this->db->quoteColumnName($oldName) . ' ' |
||
76 | . $this->db->quoteColumnName($newName) . ' ' |
||
77 | . $matches[2][$i]; |
||
78 | } |
||
79 | } |
||
80 | } |
||
81 | // try to give back a SQL anyway |
||
82 | return "ALTER TABLE $quotedTable CHANGE " |
||
83 | . $this->db->quoteColumnName($oldName) . ' ' |
||
84 | . $this->db->quoteColumnName($newName); |
||
85 | } |
||
86 | |||
87 | /** |
||
88 | * @inheritdoc |
||
89 | * @see https://bugs.mysql.com/bug.php?id=48875 |
||
90 | */ |
||
91 | 12 | public function createIndex($name, $table, $columns, $unique = false) |
|
99 | |||
100 | /** |
||
101 | * Builds a SQL statement for dropping a foreign key constraint. |
||
102 | * @param string $name the name of the foreign key constraint to be dropped. The name will be properly quoted by the method. |
||
103 | * @param string $table the table whose foreign is to be dropped. The name will be properly quoted by the method. |
||
104 | * @return string the SQL statement for dropping a foreign key constraint. |
||
105 | */ |
||
106 | 3 | public function dropForeignKey($name, $table) |
|
107 | { |
||
108 | 3 | return 'ALTER TABLE ' . $this->db->quoteTableName($table) |
|
109 | 3 | . ' DROP FOREIGN KEY ' . $this->db->quoteColumnName($name); |
|
110 | } |
||
111 | |||
112 | /** |
||
113 | * Builds a SQL statement for removing a primary key constraint to an existing table. |
||
114 | * @param string $name the name of the primary key constraint to be removed. |
||
115 | * @param string $table the table that the primary key constraint will be removed from. |
||
116 | * @return string the SQL statement for removing a primary key constraint from an existing table. |
||
117 | */ |
||
118 | 2 | public function dropPrimaryKey($name, $table) |
|
122 | |||
123 | /** |
||
124 | * @inheritDoc |
||
125 | */ |
||
126 | 2 | public function dropUnique($name, $table) |
|
130 | |||
131 | /** |
||
132 | * @inheritDoc |
||
133 | * @throws NotSupportedException this is not supported by MySQL. |
||
134 | */ |
||
135 | public function addCheck($name, $table, $expression) |
||
139 | |||
140 | /** |
||
141 | * @inheritDoc |
||
142 | * @throws NotSupportedException this is not supported by MySQL. |
||
143 | */ |
||
144 | public function dropCheck($name, $table) |
||
148 | |||
149 | /** |
||
150 | * Creates a SQL statement for resetting the sequence value of a table's primary key. |
||
151 | * The sequence will be reset such that the primary key of the next new row inserted |
||
152 | * will have the specified value or 1. |
||
153 | * @param string $tableName the name of the table whose primary key sequence will be reset |
||
154 | * @param mixed $value the value for the primary key of the next new row inserted. If this is not set, |
||
155 | * the next new row's primary key will have a value 1. |
||
156 | * @return string the SQL statement for resetting sequence |
||
157 | * @throws InvalidParamException if the table does not exist or there is no sequence associated with the table. |
||
158 | */ |
||
159 | 5 | public function resetSequence($tableName, $value = null) |
|
160 | { |
||
161 | 5 | $table = $this->db->getTableSchema($tableName); |
|
162 | 5 | if ($table !== null && $table->sequenceName !== null) { |
|
163 | 5 | $tableName = $this->db->quoteTableName($tableName); |
|
164 | 5 | if ($value === null) { |
|
165 | 1 | $key = reset($table->primaryKey); |
|
166 | 1 | $value = $this->db->createCommand("SELECT MAX(`$key`) FROM $tableName")->queryScalar() + 1; |
|
167 | } else { |
||
168 | 5 | $value = (int) $value; |
|
169 | } |
||
170 | |||
171 | 5 | return "ALTER TABLE $tableName AUTO_INCREMENT=$value"; |
|
172 | } elseif ($table === null) { |
||
173 | throw new InvalidParamException("Table not found: $tableName"); |
||
174 | } |
||
175 | |||
176 | throw new InvalidParamException("There is no sequence associated with table '$tableName'."); |
||
177 | } |
||
178 | |||
179 | /** |
||
180 | * Builds a SQL statement for enabling or disabling integrity check. |
||
181 | * @param bool $check whether to turn on or off the integrity check. |
||
182 | * @param string $schema the schema of the tables. Meaningless for MySQL. |
||
183 | * @param string $table the table name. Meaningless for MySQL. |
||
184 | * @return string the SQL statement for checking integrity |
||
185 | */ |
||
186 | 2 | public function checkIntegrity($check = true, $schema = '', $table = '') |
|
190 | |||
191 | /** |
||
192 | * @inheritdoc |
||
193 | */ |
||
194 | 306 | public function buildLimit($limit, $offset) |
|
211 | |||
212 | /** |
||
213 | * @inheritdoc |
||
214 | */ |
||
215 | 306 | protected function hasLimit($limit) |
|
220 | |||
221 | /** |
||
222 | * @inheritdoc |
||
223 | */ |
||
224 | 306 | protected function hasOffset($offset) |
|
230 | |||
231 | /** |
||
232 | * @inheritdoc |
||
233 | */ |
||
234 | 121 | public function insert($table, $columns, &$params) |
|
277 | |||
278 | /** |
||
279 | * @inheritdoc |
||
280 | * @since 2.0.8 |
||
281 | */ |
||
282 | 2 | public function addCommentOnColumn($table, $column, $comment) |
|
293 | |||
294 | /** |
||
295 | * @inheritdoc |
||
296 | * @since 2.0.8 |
||
297 | */ |
||
298 | 1 | public function addCommentOnTable($table, $comment) |
|
302 | |||
303 | /** |
||
304 | * @inheritdoc |
||
305 | * @since 2.0.8 |
||
306 | */ |
||
307 | 2 | public function dropCommentFromColumn($table, $column) |
|
311 | |||
312 | /** |
||
313 | * @inheritdoc |
||
314 | * @since 2.0.8 |
||
315 | */ |
||
316 | 1 | public function dropCommentFromTable($table) |
|
320 | |||
321 | |||
322 | /** |
||
323 | * Gets column definition. |
||
324 | * |
||
325 | * @param string $table table name |
||
326 | * @param string $column column name |
||
327 | * @return null|string the column definition |
||
328 | * @throws Exception in case when table does not contain column |
||
329 | */ |
||
330 | 2 | private function getColumnDefinition($table, $column) |
|
352 | } |
||
353 |