Complex classes like WhereStatement 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 WhereStatement, and based on these observations, apply Extract Interface, too.
1 | <?php |
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15 | class WhereStatement extends Statement |
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16 | { |
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17 | /** |
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18 | * @var bool |
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19 | */ |
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20 | protected $having; |
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21 | |||
22 | /** |
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23 | * @var array |
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24 | */ |
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25 | protected $conditions = []; |
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26 | |||
27 | /** |
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28 | * @param bool $having when true, statement becomes a having statement |
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29 | */ |
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30 | public function __construct($having = false) |
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34 | |||
35 | /** |
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36 | * Tells whether this statement is a HAVING statement. |
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37 | * |
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38 | * @return bool true: is HAVING, false: is WHERE |
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39 | */ |
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40 | public function isHaving() |
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44 | |||
45 | /** |
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46 | * Adds a condition to the statement. |
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47 | * |
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48 | * Accepts the following forms: |
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49 | * 1. Equality comparison: |
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50 | * addCondition('username', 'john') |
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51 | * 2. Comparison with custom operator: |
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52 | * addCondition('balance', 100, '>') |
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53 | * 3. IN statement: |
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54 | * addCondition('group', ['admin', 'owner']) |
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55 | * 4. SQL fragment: |
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56 | * addCondition('name LIKE "%john%"') |
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57 | * 5. Subquery: |
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58 | * addCondition(function(SelectQuery $query) {}) |
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59 | * 6. List of conditions to add: |
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60 | * addCondition([['balance', 100, '>'], |
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61 | * ['user_id', 5]]) |
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62 | * 7. Map of equality comparisons: |
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63 | * addCondition(['username' => 'john', |
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64 | * 'user_id' => 5]) |
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65 | * 8. List of SQL fragments: |
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66 | * addCondition(['first_name LIKE "%john%"', |
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67 | * 'last_name LIKE "%doe%"']) |
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68 | * |
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69 | * @param array|string $field |
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70 | * @param string|bool $value condition value (optional) |
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71 | * @param string $operator operator (optional) |
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72 | * |
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73 | * @return self |
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74 | */ |
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75 | public function addCondition($field, $value = false, $operator = '=') |
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76 | { |
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77 | if (is_array($field) && !$value) { |
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78 | foreach ($field as $key => $value) { |
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79 | // handles #6 |
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80 | if (is_array($value)) { |
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81 | call_user_func_array([$this, 'addCondition'], $value); |
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82 | // handles #7 |
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83 | } elseif (!is_numeric($key)) { |
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84 | $this->addCondition($key, $value); |
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85 | // handles #8 |
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86 | } else { |
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87 | $this->addCondition($value); |
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88 | } |
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89 | } |
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90 | |||
91 | return $this; |
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92 | } |
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93 | |||
94 | // handles #4 and #5 |
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95 | $condition = [$field]; |
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96 | |||
97 | if (func_num_args() >= 2) { |
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98 | // handles #3 |
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99 | // todo |
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100 | |||
101 | // handles #1 and #2 |
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102 | $condition[] = $operator; |
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103 | $condition[] = $value; |
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104 | } |
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105 | |||
106 | $this->conditions[] = $condition; |
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107 | |||
108 | return $this; |
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109 | } |
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110 | |||
111 | /** |
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112 | * Adds an OR condition. Uses same arguments as |
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113 | * adding AND conditions. |
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114 | * |
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115 | * @return self |
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116 | */ |
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117 | public function addOrCondition() |
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118 | { |
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119 | $this->conditions[] = ['OR']; |
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120 | |||
121 | return call_user_func_array([$this, 'addCondition'], func_get_args()); |
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122 | } |
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123 | |||
124 | /** |
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125 | * Adds a between condition to the query. |
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126 | * |
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127 | * @param string $field |
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128 | * @param mixed $a first between value |
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129 | * @param mixed $b second between value |
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130 | * |
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131 | * @return self |
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132 | */ |
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133 | public function addBetweenCondition($field, $a, $b) |
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134 | { |
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135 | $this->conditions[] = ['BETWEEN', $field, $a, $b, true]; |
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136 | |||
137 | return $this; |
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138 | } |
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139 | |||
140 | /** |
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141 | * Adds a not between condition to the query. |
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142 | * |
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143 | * @param string $field |
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144 | * @param mixed $a first between value |
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145 | * @param mixed $b second between value |
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146 | * |
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147 | * @return self |
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148 | */ |
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149 | public function addNotBetweenCondition($field, $a, $b) |
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150 | { |
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151 | $this->conditions[] = ['BETWEEN', $field, $a, $b, false]; |
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152 | |||
153 | return $this; |
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154 | } |
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155 | |||
156 | /** |
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157 | * Adds an exists condition to the query. |
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158 | * |
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159 | * @param callable $f |
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160 | * |
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161 | * @return self |
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162 | */ |
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163 | public function addExistsCondition(callable $f) |
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164 | { |
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165 | $this->conditions[] = ['EXISTS', $f, true]; |
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166 | |||
167 | return $this; |
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168 | } |
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169 | |||
170 | /** |
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171 | * Adds a not exists condition to the query. |
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172 | * |
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173 | * @param callable $f |
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174 | * |
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175 | * @return self |
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176 | */ |
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177 | public function addNotExistsCondition(callable $f) |
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178 | { |
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179 | $this->conditions[] = ['EXISTS', $f, false]; |
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180 | |||
181 | return $this; |
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182 | } |
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183 | |||
184 | /** |
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185 | * Gets the conditions for this statement. |
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186 | * |
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187 | * @return array |
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188 | */ |
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189 | public function getConditions() |
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190 | { |
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191 | return $this->conditions; |
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192 | } |
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193 | |||
194 | public function build() |
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195 | { |
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196 | // reset the parameterized values |
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197 | $this->values = []; |
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198 | |||
199 | // build clause from conditions |
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200 | $clauses = []; |
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201 | foreach ($this->conditions as $condition) { |
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202 | $clauses[] = $this->buildClause($condition); |
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203 | } |
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204 | |||
205 | // remove empty values |
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206 | $clauses = array_filter($clauses); |
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207 | |||
208 | if (count($clauses) == 0) { |
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209 | return ''; |
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210 | } |
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211 | |||
212 | return ((!$this->having) ? 'WHERE ' : 'HAVING ').$this->implodeClauses($clauses); |
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213 | } |
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214 | |||
215 | /** |
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216 | * Builds a parameterized and escaped SQL fragment |
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217 | * for a condition that uses our own internal |
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218 | * representation. |
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219 | * |
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220 | * A condition is represented by an array, and can be |
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221 | * have one of the following forms: |
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222 | * 1. ['SQL fragment'] |
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223 | * 2. ['identifier', '=', 'value'] |
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224 | * 3. ['BETWEEN', 'identifier', 'value', 'value', true] |
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225 | * 4. ['EXISTS', function(SelectQuery $query) {}, true] |
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226 | * 5. [function(SelectQuery $query) {}] |
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227 | * 6. [function(SelectQuery $query) {}, '=', 'value'] |
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228 | * |
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229 | * @param array $cond |
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230 | * |
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231 | * @return string generated SQL fragment |
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232 | */ |
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233 | protected function buildClause(array $cond) |
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234 | { |
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235 | // handle SQL fragments |
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236 | if (count($cond) == 1 && (is_string($cond[0]) || !is_callable($cond[0]))) { |
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237 | return $cond[0]; |
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238 | } |
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239 | |||
240 | // handle EXISTS conditions |
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241 | if ($cond[0] === 'EXISTS') { |
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242 | return $this->buildExists($cond[1], $cond[2]); |
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243 | } |
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244 | |||
245 | // handle BETWEEN conditions |
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246 | if ($cond[0] === 'BETWEEN') { |
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247 | return $this->buildBetween($cond[1], $cond[2], $cond[3], $cond[4]); |
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248 | } |
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249 | |||
250 | // escape an identifier |
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251 | if (is_string($cond[0]) || !is_callable($cond[0])) { |
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252 | $cond[0] = $this->escapeIdentifier($cond[0]); |
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253 | |||
254 | // handle a subquery |
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255 | // NOTE string callables are not supported |
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256 | // as subquery functions |
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257 | } elseif (is_callable($cond[0])) { |
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258 | $cond[0] = $this->buildSubquery($cond[0]); |
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259 | } |
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260 | |||
261 | if (count($cond) === 1 || empty($cond[0])) { |
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262 | return $cond[0]; |
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263 | } |
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264 | |||
265 | // handle NULL values |
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266 | if ($cond[2] === null && in_array($cond[1], ['=', '<>'])) { |
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267 | return $this->buildNull($cond[0], $cond[1] == '='); |
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268 | } |
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269 | |||
270 | // handle IN values |
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271 | if (is_array($cond[2]) && in_array($cond[1], ['=', '<>'])) { |
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272 | return $this->buildIn($cond[0], $cond[2], $cond[1] == '='); |
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273 | } |
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274 | |||
275 | // otherwise parameterize the value |
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276 | $cond[2] = $this->parameterize($cond[2]); |
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277 | |||
278 | return implode(' ', $cond); |
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279 | } |
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280 | |||
281 | /** |
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282 | * Builds a subquery. |
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283 | * |
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284 | * @param callable $f |
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285 | * |
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286 | * @return string |
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287 | */ |
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288 | protected function buildSubquery(callable $f) |
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298 | |||
299 | /** |
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300 | * Builds an EXISTS clause. |
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301 | * |
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302 | * @param callable $f |
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303 | * @param bool $isExists |
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304 | * |
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305 | * @return string |
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306 | */ |
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307 | protected function buildExists(callable $f, $isExists) |
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313 | |||
314 | /** |
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315 | * Builds a BETWEEN clause. |
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316 | * |
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317 | * @param string $field |
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318 | * @param mixed $value1 |
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319 | * @param mixed $value2 |
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320 | * @param bool $isBetween |
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321 | * |
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322 | * @return string |
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323 | */ |
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324 | protected function buildBetween($field, $value1, $value2, $isBetween) |
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325 | { |
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326 | $operator = $isBetween ? 'BETWEEN' : 'NOT BETWEEN'; |
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327 | |||
328 | return $this->escapeIdentifier($field).' '.$operator.' '.$this->parameterize($value1).' AND '.$this->parameterize($value2); |
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329 | } |
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330 | |||
331 | /** |
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332 | * Builds a NULL clause. |
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333 | * |
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334 | * @param string $field |
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335 | * @param bool $isEqual |
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336 | * |
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337 | * @return string |
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338 | */ |
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339 | protected function buildNull($field, $isEqual) |
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345 | |||
346 | protected function buildIn($field, $values, $isIn) |
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347 | { |
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348 | $operator = $isIn ? ' IN ' : ' NOT IN '; |
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349 | |||
350 | return $field.$operator.$this->parameterizeValues($values); |
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351 | } |
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352 | |||
353 | /** |
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354 | * Implodes a list of WHERE clauses. |
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355 | * |
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356 | * @param array $clauses |
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357 | * |
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358 | * @return string |
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359 | */ |
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360 | protected function implodeClauses(array $clauses) |
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382 | } |
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383 |
It seems like the type of the argument is not accepted by the function/method which you are calling.
In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.
We suggest to add an explicit type cast like in the following example: