Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
| 1 | <?php  | 
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| 40 | class CirclesRequestBuilder { | 
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| 41 | |||
| 42 | const TABLE_CIRCLES = 'circles_circles';  | 
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| 43 | const TABLE_MEMBERS = 'circles_members';  | 
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| 44 | |||
| 45 | /** @var IDBConnection */  | 
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| 46 | protected $dbConnection;  | 
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| 47 | |||
| 48 | /** @var L10N */  | 
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| 49 | protected $l10n;  | 
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| 50 | |||
| 51 | private $default_select_alias;  | 
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| 52 | |||
| 53 | |||
| 54 | /**  | 
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| 55 | * Join the Circles table  | 
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| 56 | *  | 
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| 57 | * @param IQueryBuilder $qb  | 
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| 58 | */  | 
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| 59 | 	protected function joinCircles(& $qb, $field) { | 
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| 65 | |||
| 66 | |||
| 67 | /**  | 
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| 68 | * Limit the request to the Share by its Id.  | 
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| 69 | *  | 
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| 70 | * @param IQueryBuilder $qb  | 
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| 71 | * @param int $circleId  | 
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| 72 | */  | 
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| 73 | 	protected function limitToCircleId(IQueryBuilder &$qb, $circleId) { | 
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| 79 | |||
| 80 | |||
| 81 | /**  | 
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| 82 | * Limit the request by its Id.  | 
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| 83 | *  | 
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| 84 | * @param IQueryBuilder $qb  | 
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| 85 | * @param int $id  | 
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| 86 | */  | 
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| 87 | 	protected function limitToId(IQueryBuilder &$qb, $id) { | 
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| 93 | |||
| 94 | |||
| 95 | /**  | 
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| 96 | * Limit the request by its UniqueId.  | 
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| 97 | *  | 
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| 98 | * @param IQueryBuilder $qb  | 
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| 99 | * @param int $uniqueId  | 
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| 100 | */  | 
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| 101 | 	protected function limitToUniqueId(IQueryBuilder &$qb, $uniqueId) { | 
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| 107 | |||
| 108 | |||
| 109 | /**  | 
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| 110 | * Limit the request by its Token.  | 
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| 111 | *  | 
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| 112 | * @param IQueryBuilder $qb  | 
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| 113 | * @param $token  | 
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| 114 | */  | 
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| 115 | 	protected function limitToToken(IQueryBuilder &$qb, $token) { | 
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| 121 | |||
| 122 | |||
| 123 | /**  | 
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| 124 | * Limit the request to a minimum member level.  | 
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| 125 | *  | 
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| 126 | * @param IQueryBuilder $qb  | 
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| 127 | * @param $level  | 
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| 128 | */  | 
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| 129 | 	protected function limitToMemberLevel(IQueryBuilder &$qb, $level) { | 
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| 135 | |||
| 136 | |||
| 137 | /**  | 
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| 138 | * add a request to the members list, using the current user ID.  | 
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| 139 | * will returns level and stuff.  | 
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| 140 | *  | 
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| 141 | * @param IQueryBuilder $qb  | 
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| 142 | * @param string $userId  | 
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| 143 | */  | 
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| 144 | 	protected function leftJoinUserIdAsMember(IQueryBuilder &$qb, $userId) { | 
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| 162 | |||
| 163 | /**  | 
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| 164 | * @param IQueryBuilder $qb  | 
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| 165 | *  | 
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| 166 | * @deprecated  | 
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| 167 | * never used in fact.  | 
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| 168 | */  | 
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| 169 | 	protected function leftJoinOwner(IQueryBuilder &$qb) { | 
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| 186 | |||
| 187 | |||
| 188 | /**  | 
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| 189 | * Base of the Sql Select request for Shares  | 
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| 190 | *  | 
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| 191 | * @return IQueryBuilder  | 
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| 192 | */  | 
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| 193 | 	protected function getLinksSelectSql() { | 
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| 203 | |||
| 204 | |||
| 205 | /**  | 
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| 206 | * Base of the Sql Select request for Shares  | 
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| 207 | *  | 
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| 208 | * @return IQueryBuilder  | 
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| 209 | */  | 
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| 210 | 	protected function getSharesSelectSql() { | 
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| 223 | |||
| 224 | /**  | 
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| 225 | * Base of the Sql Insert request for Shares  | 
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| 226 | *  | 
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| 227 | * @return IQueryBuilder  | 
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| 228 | */  | 
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| 229 | 	protected function getSharesInsertSql() { | 
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| 236 | |||
| 237 | |||
| 238 | /**  | 
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| 239 | * Base of the Sql Update request for Shares  | 
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| 240 | *  | 
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| 241 | * @param string $uniqueId  | 
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| 242 | *  | 
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| 243 | * @return IQueryBuilder  | 
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| 244 | */  | 
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| 245 | 	protected function getSharesUpdateSql(string $uniqueId) { | 
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| 255 | |||
| 256 | |||
| 257 | /**  | 
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| 258 | * @return IQueryBuilder  | 
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| 259 | */  | 
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| 260 | 	protected function getMembersSelectSql() { | 
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| 270 | |||
| 271 | |||
| 272 | /**  | 
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| 273 | * @return IQueryBuilder  | 
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| 274 | */  | 
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| 275 | 	protected function getCirclesSelectSql() { | 
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| 284 | |||
| 285 | /**  | 
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| 286 | * @param array $data  | 
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| 287 | *  | 
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| 288 | * @return Member  | 
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| 289 | */  | 
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| 290 | 	protected function parseMembersSelectSql(array $data) { | 
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| 300 | |||
| 301 | |||
| 302 | /**  | 
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| 303 | * @param array $data  | 
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| 304 | *  | 
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| 305 | * @return Circle  | 
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| 306 | */  | 
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| 307 | 	protected function parseCirclesSelectSql($data) { | 
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| 328 | |||
| 329 | |||
| 330 | /**  | 
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| 331 | * @param array $data  | 
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| 332 | *  | 
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| 333 | * @return SharingFrame  | 
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| 334 | */  | 
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| 335 | 	protected function parseSharesSelectSql($data) { | 
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| 351 | |||
| 352 | |||
| 353 | /**  | 
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| 354 | * @param array $data  | 
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| 355 | *  | 
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| 356 | * @return FederatedLink  | 
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| 357 | */  | 
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| 358 | View Code Duplication | 	public function parseLinksSelectSql($data) { | 
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| 373 | |||
| 374 | |||
| 375 | }  | 
            
This check marks property names that have not been written in camelCase.
In camelCase names are written without any punctuation, the start of each new word being marked by a capital letter. Thus the name database connection string becomes
databaseConnectionString.