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 |
||
20 | class QueryBuilder extends \yii\db\QueryBuilder |
||
21 | { |
||
22 | /** |
||
23 | * @var array mapping from abstract column types (keys) to physical column types (values). |
||
24 | */ |
||
25 | public $typeMap = [ |
||
26 | Schema::TYPE_PK => 'int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
27 | Schema::TYPE_UPK => 'int(10) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
28 | Schema::TYPE_BIGPK => 'bigint(20) NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
29 | Schema::TYPE_UBIGPK => 'bigint(20) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY', |
||
30 | Schema::TYPE_CHAR => 'char(1)', |
||
31 | Schema::TYPE_STRING => 'varchar(255)', |
||
32 | Schema::TYPE_TEXT => 'text', |
||
33 | Schema::TYPE_SMALLINT => 'smallint(6)', |
||
34 | Schema::TYPE_INTEGER => 'int(11)', |
||
35 | Schema::TYPE_BIGINT => 'bigint(20)', |
||
36 | Schema::TYPE_FLOAT => 'float', |
||
37 | Schema::TYPE_DOUBLE => 'double', |
||
38 | Schema::TYPE_DECIMAL => 'decimal(10,0)', |
||
39 | Schema::TYPE_DATETIME => 'datetime', |
||
40 | Schema::TYPE_TIMESTAMP => 'timestamp', |
||
41 | Schema::TYPE_TIME => 'time', |
||
42 | Schema::TYPE_DATE => 'date', |
||
43 | Schema::TYPE_BINARY => 'blob', |
||
44 | Schema::TYPE_BOOLEAN => 'tinyint(1)', |
||
45 | Schema::TYPE_MONEY => 'decimal(19,4)', |
||
46 | ]; |
||
47 | |||
48 | |||
49 | /** |
||
50 | * Builds a SQL statement for renaming a column. |
||
51 | * @param string $table the table whose column is to be renamed. The name will be properly quoted by the method. |
||
52 | * @param string $oldName the old name of the column. The name will be properly quoted by the method. |
||
53 | * @param string $newName the new name of the column. The name will be properly quoted by the method. |
||
54 | * @return string the SQL statement for renaming a DB column. |
||
55 | * @throws Exception |
||
56 | */ |
||
57 | public function renameColumn($table, $oldName, $newName) |
||
58 | { |
||
59 | $quotedTable = $this->db->quoteTableName($table); |
||
60 | $row = $this->db->createCommand('SHOW CREATE TABLE ' . $quotedTable)->queryOne(); |
||
61 | if ($row === false) { |
||
62 | throw new Exception("Unable to find column '$oldName' in table '$table'."); |
||
63 | } |
||
64 | if (isset($row['Create Table'])) { |
||
65 | $sql = $row['Create Table']; |
||
66 | } else { |
||
67 | $row = array_values($row); |
||
68 | $sql = $row[1]; |
||
69 | } |
||
70 | if (preg_match_all('/^\s*`(.*?)`\s+(.*?),?$/m', $sql, $matches)) { |
||
71 | foreach ($matches[1] as $i => $c) { |
||
72 | if ($c === $oldName) { |
||
73 | return "ALTER TABLE $quotedTable CHANGE " |
||
74 | . $this->db->quoteColumnName($oldName) . ' ' |
||
75 | . $this->db->quoteColumnName($newName) . ' ' |
||
76 | . $matches[2][$i]; |
||
77 | } |
||
78 | } |
||
79 | } |
||
80 | // try to give back a SQL anyway |
||
81 | return "ALTER TABLE $quotedTable CHANGE " |
||
82 | . $this->db->quoteColumnName($oldName) . ' ' |
||
83 | . $this->db->quoteColumnName($newName); |
||
84 | } |
||
85 | |||
86 | /** |
||
87 | * @inheritdoc |
||
88 | * @see https://bugs.mysql.com/bug.php?id=48875 |
||
89 | */ |
||
90 | public function createIndex($name, $table, $columns, $unique = false) |
||
98 | |||
99 | /** |
||
100 | * Builds a SQL statement for dropping a foreign key constraint. |
||
101 | * @param string $name the name of the foreign key constraint to be dropped. The name will be properly quoted by the method. |
||
102 | * @param string $table the table whose foreign is to be dropped. The name will be properly quoted by the method. |
||
103 | * @return string the SQL statement for dropping a foreign key constraint. |
||
104 | */ |
||
105 | public function dropForeignKey($name, $table) |
||
110 | |||
111 | /** |
||
112 | * Builds a SQL statement for removing a primary key constraint to an existing table. |
||
113 | * @param string $name the name of the primary key constraint to be removed. |
||
114 | * @param string $table the table that the primary key constraint will be removed from. |
||
115 | * @return string the SQL statement for removing a primary key constraint from an existing table. |
||
116 | */ |
||
117 | public function dropPrimaryKey($name, $table) |
||
118 | { |
||
119 | return 'ALTER TABLE ' . $this->db->quoteTableName($table) . ' DROP PRIMARY KEY'; |
||
120 | } |
||
121 | |||
122 | /** |
||
123 | * Creates a SQL statement for resetting the sequence value of a table's primary key. |
||
124 | * The sequence will be reset such that the primary key of the next new row inserted |
||
125 | * will have the specified value or 1. |
||
126 | * @param string $tableName the name of the table whose primary key sequence will be reset |
||
127 | * @param mixed $value the value for the primary key of the next new row inserted. If this is not set, |
||
128 | * the next new row's primary key will have a value 1. |
||
129 | * @return string the SQL statement for resetting sequence |
||
130 | * @throws InvalidParamException if the table does not exist or there is no sequence associated with the table. |
||
131 | */ |
||
132 | 1 | public function resetSequence($tableName, $value = null) |
|
133 | { |
||
134 | 1 | $table = $this->db->getTableSchema($tableName); |
|
135 | if ($table !== null && $table->sequenceName !== null) { |
||
136 | $tableName = $this->db->quoteTableName($tableName); |
||
137 | if ($value === null) { |
||
138 | $key = reset($table->primaryKey); |
||
139 | $value = $this->db->createCommand("SELECT MAX(`$key`) FROM $tableName")->queryScalar() + 1; |
||
140 | } else { |
||
141 | $value = (int) $value; |
||
142 | } |
||
143 | |||
144 | return "ALTER TABLE $tableName AUTO_INCREMENT=$value"; |
||
145 | } elseif ($table === null) { |
||
146 | throw new InvalidParamException("Table not found: $tableName"); |
||
147 | } else { |
||
148 | throw new InvalidParamException("There is no sequence associated with table '$tableName'."); |
||
149 | } |
||
150 | } |
||
151 | |||
152 | /** |
||
153 | * Builds a SQL statement for enabling or disabling integrity check. |
||
154 | * @param bool $check whether to turn on or off the integrity check. |
||
155 | * @param string $schema the schema of the tables. Meaningless for MySQL. |
||
156 | * @param string $table the table name. Meaningless for MySQL. |
||
157 | * @return string the SQL statement for checking integrity |
||
158 | */ |
||
159 | public function checkIntegrity($check = true, $schema = '', $table = '') |
||
163 | |||
164 | /** |
||
165 | * @inheritdoc |
||
166 | */ |
||
167 | 98 | public function buildLimit($limit, $offset) |
|
168 | { |
||
169 | 98 | $sql = ''; |
|
170 | 98 | if ($this->hasLimit($limit)) { |
|
171 | $sql = 'LIMIT ' . $limit; |
||
172 | if ($this->hasOffset($offset)) { |
||
173 | $sql .= ' OFFSET ' . $offset; |
||
174 | } |
||
175 | 98 | } elseif ($this->hasOffset($offset)) { |
|
176 | // limit is not optional in MySQL |
||
177 | // http://stackoverflow.com/a/271650/1106908 |
||
178 | // http://dev.mysql.com/doc/refman/5.0/en/select.html#idm47619502796240 |
||
179 | $sql = "LIMIT $offset, 18446744073709551615"; // 2^64-1 |
||
180 | } |
||
181 | |||
182 | 98 | return $sql; |
|
183 | } |
||
184 | |||
185 | /** |
||
186 | * @inheritdoc |
||
187 | */ |
||
188 | 98 | protected function hasLimit($limit) |
|
193 | |||
194 | /** |
||
195 | * @inheritdoc |
||
196 | */ |
||
197 | 98 | protected function hasOffset($offset) |
|
203 | |||
204 | /** |
||
205 | * @inheritdoc |
||
206 | */ |
||
207 | public function insert($table, $columns, &$params) |
||
208 | { |
||
209 | $schema = $this->db->getSchema(); |
||
210 | if (($tableSchema = $schema->getTableSchema($table)) !== null) { |
||
211 | $columnSchemas = $tableSchema->columns; |
||
212 | } else { |
||
213 | $columnSchemas = []; |
||
214 | } |
||
215 | $names = []; |
||
216 | $placeholders = []; |
||
217 | $values = ' DEFAULT VALUES'; |
||
218 | if ($columns instanceof \yii\db\Query) { |
||
219 | list($names, $values, $params) = $this->prepareInsertSelectSubQuery($columns, $schema, $params); |
||
220 | } else { |
||
221 | foreach ($columns as $name => $value) { |
||
222 | $names[] = $schema->quoteColumnName($name); |
||
223 | if ($value instanceof Expression) { |
||
224 | $placeholders[] = $value->expression; |
||
225 | foreach ($value->params as $n => $v) { |
||
226 | $params[$n] = $v; |
||
227 | } |
||
228 | } elseif ($value instanceof \yii\db\Query) { |
||
229 | list($sql, $params) = $this->build($value, $params); |
||
230 | $placeholders[] = "($sql)"; |
||
231 | } else { |
||
232 | $phName = self::PARAM_PREFIX . count($params); |
||
233 | $placeholders[] = $phName; |
||
234 | $params[$phName] = !is_array($value) && isset($columnSchemas[$name]) ? $columnSchemas[$name]->dbTypecast($value) : $value; |
||
235 | } |
||
236 | } |
||
237 | if (empty($names) && $tableSchema !== null) { |
||
238 | $columns = !empty($tableSchema->primaryKey) ? $tableSchema->primaryKey : [reset($tableSchema->columns)->name]; |
||
239 | foreach ($columns as $name) { |
||
240 | $names[] = $schema->quoteColumnName($name); |
||
241 | $placeholders[] = 'DEFAULT'; |
||
242 | } |
||
243 | } |
||
244 | } |
||
245 | |||
246 | return 'INSERT INTO ' . $schema->quoteTableName($table) |
||
247 | . (!empty($names) ? ' (' . implode(', ', $names) . ')' : '') |
||
248 | . (!empty($placeholders) ? ' VALUES (' . implode(', ', $placeholders) . ')' : $values); |
||
249 | } |
||
250 | |||
251 | /** |
||
252 | * @inheritdoc |
||
253 | * @since 2.0.8 |
||
254 | */ |
||
255 | 1 | public function addCommentOnColumn($table, $column, $comment) |
|
256 | { |
||
257 | 1 | $definition = $this->getColumnDefinition($table, $column); |
|
258 | $definition = trim(preg_replace("/COMMENT '(.*?)'/i", '', $definition)); |
||
259 | |||
260 | return 'ALTER TABLE ' . $this->db->quoteTableName($table) |
||
261 | . ' CHANGE ' . $this->db->quoteColumnName($column) |
||
262 | . ' ' . $this->db->quoteColumnName($column) |
||
263 | . (empty($definition) ? '' : ' ' . $definition) |
||
264 | . ' COMMENT ' . $this->db->quoteValue($comment); |
||
265 | } |
||
266 | |||
267 | /** |
||
268 | * @inheritdoc |
||
269 | * @since 2.0.8 |
||
270 | */ |
||
271 | 1 | public function addCommentOnTable($table, $comment) |
|
275 | |||
276 | /** |
||
277 | * @inheritdoc |
||
278 | * @since 2.0.8 |
||
279 | */ |
||
280 | public function dropCommentFromColumn($table, $column) |
||
284 | |||
285 | /** |
||
286 | * @inheritdoc |
||
287 | * @since 2.0.8 |
||
288 | */ |
||
289 | public function dropCommentFromTable($table) |
||
293 | |||
294 | |||
295 | /** |
||
296 | * Gets column definition. |
||
297 | * |
||
298 | * @param string $table table name |
||
299 | * @param string $column column name |
||
300 | * @return null|string the column definition |
||
301 | * @throws Exception in case when table does not contain column |
||
302 | */ |
||
303 | 1 | private function getColumnDefinition($table, $column) |
|
325 | } |
||
326 |