1: <?php
  2: 
  3: namespace zsql;
  4: 
  5: /**
  6:  * Select query generator
  7:  */
  8: class Select extends ExtendedQuery
  9: {
 10:   /**
 11:    * Columns clause
 12:    * 
 13:    * @var mixed
 14:    */
 15:   protected $columns;
 16:   
 17:   /**
 18:    * Distinct clause
 19:    * 
 20:    * @var boolean
 21:    */
 22:   protected $distinct;
 23:   
 24:   /**
 25:    * Index hint clause (column)
 26:    * 
 27:    * @var string
 28:    */
 29:   protected $hint;
 30:   
 31:   /**
 32:    * Index hint clause (mode)
 33:    * 
 34:    * @var string
 35:    */
 36:   protected $hintMode;
 37:   
 38:   /**
 39:    * The result class
 40:    * 
 41:    * @var string
 42:    */
 43:   protected $resultClass;
 44:   
 45:   /**
 46:    * Set the columns
 47:    * 
 48:    * @param mixed $columns
 49:    * @return \zsql\Select
 50:    * @throws \zsql\Exception
 51:    */
 52:   public function columns($columns)
 53:   {
 54:     if( is_array($columns) || 
 55:         is_string($columns) ||
 56:         $columns instanceof Expression ) {
 57:       $this->columns = $columns;
 58:     } else {
 59:       throw new \zsql\Exception('Invalid columns parameter');
 60:     }
 61:     return $this;
 62:   }
 63:   
 64:   /**
 65:    * Set distinct clause
 66:    * 
 67:    * @param type $distinct
 68:    * @return \zsql\Select
 69:    */
 70:   public function distinct($distinct = true)
 71:   {
 72:     $this->distinct = (bool) $distinct;
 73:     return $this;
 74:   }
 75:   
 76:   /**
 77:    * Alias for {@link Query::table()} and {@link Select::columns()}
 78:    * 
 79:    * @param mixed $table
 80:    * @param mixed $columns
 81:    * @return \zsql\Select
 82:    */
 83:   public function from($table, $columns = null)
 84:   {
 85:     $this->table($table);
 86:     if( !empty($columns) ) {
 87:       $this->columns($columns);
 88:     }
 89:     return $this;
 90:   }
 91:   
 92:   /**
 93:    * Hint at index to use
 94:    * 
 95:    * @param mixed $columns
 96:    * @param string $mode
 97:    * @return \zsql\Select
 98:    */
 99:   public function hint($columns, $mode = null)
100:   {
101:     $this->hint = $columns;
102:     $this->hintMode = $mode;
103:     return $this;
104:   }
105:   
106:   /**
107:    * Alias for {@link Select::columns()}
108:    * 
109:    * @param mixed $columns
110:    * @return \zsql\Select
111:    */
112:   public function select($columns)
113:   {
114:     $this->columns($columns);
115:     return $this;
116:   }
117:   
118:   /**
119:    * Get the result class
120:    * 
121:    * @return string
122:    */
123:   public function getResultClass()
124:   {
125:     return $this->resultClass;
126:   }
127:   
128:   /**
129:    * Set result class
130:    * 
131:    * @param string $class
132:    * @return \zsql\Select
133:    */
134:   public function setResultClass($class)
135:   {
136:     $this->resultClass = $class;
137:     return $this;
138:   }
139:   
140:   /**
141:    * Execute a query
142:    * 
143:    * @return \zsql\Result
144:    */
145:   public function query()
146:   {
147:     $result = parent::query();
148:     if( $this->resultClass ) {
149:       $result->setResultClass($this->getResultClass());
150:     }
151:     return $result;
152:   }
153:   
154:   /**
155:    * Assemble parts
156:    * 
157:    * @return void
158:    */
159:   protected function assemble()
160:   {
161:     $this->push('SELECT')
162:          ->pushDistinct()
163:          ->pushColumns()
164:          ->push('FROM')
165:          ->pushTable()
166:          ->pushHint()
167:          ->pushWhere()
168:          ->pushGroup()
169:          ->pushOrder()
170:          ->pushLimit();
171:   }
172:   
173:   /**
174:    * Push columns onto parts
175:    * 
176:    * @return \zsql\Select
177:    */
178:   protected function pushColumns()
179:   {
180:     if( !$this->columns || $this->columns == '*' ) {
181:       $this->parts[] = '*';
182:     } else if( is_array($this->columns) ) {
183:       $cols = array();
184:       foreach( $this->columns as $col ) {
185:         $cols[] = $this->quoteIdentifierIfNotExpression($col);
186:       }
187:       $this->parts[] = join(', ', $cols);
188:     } else if( is_string($this->columns) ) {
189:       $this->parts[] = $this->quoteIdentifierIfNotExpression($this->columns);
190:     } else if( $this->columns instanceof Expression ) {
191:       $this->parts[] = (string) $this->columns;
192:     }
193:     return $this;
194:   }
195:   
196:   /**
197:    * Push distinct onto parts
198:    * 
199:    * @return \zsql\Select
200:    */
201:   protected function pushDistinct()
202:   {
203:     if( $this->distinct ) {
204:       $this->parts[] = 'DISTINCT';
205:     }
206:     return $this;
207:   }
208:   
209:   /**
210:    * Push hint onto parts
211:    * 
212:    * @return \zsql\Select
213:    */
214:   protected function pushHint()
215:   {
216:     if( $this->hint ) {
217:       $this->parts[] = $this->hintMode ?: 'USE';
218:       $this->parts[] = 'INDEX';
219:       if( is_array($this->hint) ) {
220:         $this->parts[] = '(' . join(', ', array_map(array($this, 'quoteIdentifierIfNotExpression'), $this->hint)) . ')';
221:       } else {
222:         $this->parts[] = '(' . $this->quoteIdentifierIfNotExpression($this->hint) . ')';
223:       }
224:     }
225:     return $this;
226:   }
227: }
228: