Total Complexity | 75 |
Total Lines | 845 |
Duplicated Lines | 0 % |
Changes | 0 |
Complex classes like Database 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.
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 Database, and based on these observations, apply Extract Interface, too.
1 | <?php |
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19 | abstract class Database |
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20 | { |
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21 | |||
22 | /** |
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23 | * Database connector object |
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24 | * |
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25 | * @var DBConnector |
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26 | */ |
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27 | protected $connector = null; |
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28 | |||
29 | /** |
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30 | * In cases where your environment does not have 'SHOW DATABASES' permission, |
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31 | * you can set this to true. Then selectDatabase() will always connect without |
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32 | * doing databaseExists() check. |
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33 | * |
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34 | * @var bool |
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35 | */ |
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36 | private static $optimistic_connect = false; |
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37 | |||
38 | /** |
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39 | * Amount of queries executed, for debugging purposes. |
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40 | * |
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41 | * @var int |
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42 | */ |
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43 | protected $queryCount = 0; |
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44 | |||
45 | /** |
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46 | * Get the current connector |
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47 | * |
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48 | * @return DBConnector |
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49 | */ |
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50 | public function getConnector() |
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51 | { |
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52 | return $this->connector; |
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53 | } |
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54 | |||
55 | /** |
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56 | * Injector injection point for connector dependency |
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57 | * |
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58 | * @param DBConnector $connector |
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59 | */ |
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60 | public function setConnector(DBConnector $connector) |
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61 | { |
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62 | $this->connector = $connector; |
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63 | } |
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64 | |||
65 | /** |
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66 | * Database schema manager object |
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67 | * |
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68 | * @var DBSchemaManager |
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69 | */ |
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70 | protected $schemaManager = null; |
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71 | |||
72 | /** |
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73 | * Returns the current schema manager |
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74 | * |
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75 | * @return DBSchemaManager |
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76 | */ |
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77 | public function getSchemaManager() |
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80 | } |
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81 | |||
82 | /** |
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83 | * Injector injection point for schema manager |
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84 | * |
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85 | * @param DBSchemaManager $schemaManager |
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86 | */ |
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87 | public function setSchemaManager(DBSchemaManager $schemaManager) |
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88 | { |
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89 | $this->schemaManager = $schemaManager; |
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90 | |||
91 | if ($this->schemaManager) { |
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92 | $this->schemaManager->setDatabase($this); |
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93 | } |
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94 | } |
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95 | |||
96 | /** |
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97 | * Query builder object |
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98 | * |
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99 | * @var DBQueryBuilder |
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100 | */ |
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101 | protected $queryBuilder = null; |
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102 | |||
103 | /** |
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104 | * Returns the current query builder |
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105 | * |
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106 | * @return DBQueryBuilder |
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107 | */ |
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108 | public function getQueryBuilder() |
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109 | { |
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110 | return $this->queryBuilder; |
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111 | } |
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112 | |||
113 | /** |
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114 | * Injector injection point for schema manager |
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115 | * |
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116 | * @param DBQueryBuilder $queryBuilder |
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117 | */ |
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118 | public function setQueryBuilder(DBQueryBuilder $queryBuilder) |
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119 | { |
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120 | $this->queryBuilder = $queryBuilder; |
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121 | } |
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122 | |||
123 | /** |
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124 | * Execute the given SQL query. |
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125 | * |
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126 | * @param string $sql The SQL query to execute |
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127 | * @param int $errorLevel The level of error reporting to enable for the query |
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128 | * @return Query |
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129 | */ |
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130 | public function query($sql, $errorLevel = E_USER_ERROR) |
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131 | { |
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132 | // Check if we should only preview this query |
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133 | if ($this->previewWrite($sql)) { |
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134 | return null; |
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135 | } |
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136 | |||
137 | // Benchmark query |
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138 | $connector = $this->connector; |
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139 | return $this->benchmarkQuery( |
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140 | $sql, |
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141 | function ($sql) use ($connector, $errorLevel) { |
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142 | return $connector->query($sql, $errorLevel); |
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143 | } |
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144 | ); |
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145 | } |
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146 | |||
147 | |||
148 | /** |
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149 | * Execute the given SQL parameterised query with the specified arguments |
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150 | * |
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151 | * @param string $sql The SQL query to execute. The ? character will denote parameters. |
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152 | * @param array $parameters An ordered list of arguments. |
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153 | * @param int $errorLevel The level of error reporting to enable for the query |
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154 | * @return Query |
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155 | */ |
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156 | public function preparedQuery($sql, $parameters, $errorLevel = E_USER_ERROR) |
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157 | { |
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158 | // Check if we should only preview this query |
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159 | if ($this->previewWrite($sql)) { |
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160 | return null; |
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161 | } |
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162 | |||
163 | // Benchmark query |
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164 | $connector = $this->connector; |
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165 | return $this->benchmarkQuery( |
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166 | $sql, |
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167 | function ($sql) use ($connector, $parameters, $errorLevel) { |
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168 | return $connector->preparedQuery($sql, $parameters, $errorLevel); |
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169 | }, |
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170 | $parameters |
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171 | ); |
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172 | } |
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173 | |||
174 | /** |
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175 | * Determines if the query should be previewed, and thus interrupted silently. |
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176 | * If so, this function also displays the query via the debuging system. |
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177 | * Subclasess should respect the results of this call for each query, and not |
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178 | * execute any queries that generate a true response. |
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179 | * |
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180 | * @param string $sql The query to be executed |
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181 | * @return boolean Flag indicating that the query was previewed |
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182 | */ |
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183 | protected function previewWrite($sql) |
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184 | { |
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185 | // Only preview if previewWrite is set, we are in dev mode, and |
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186 | // the query is mutable |
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187 | if (isset($_REQUEST['previewwrite']) |
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188 | && Director::isDev() |
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189 | && $this->connector->isQueryMutable($sql) |
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190 | ) { |
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191 | // output preview message |
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192 | Debug::message("Will execute: $sql"); |
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193 | return true; |
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194 | } else { |
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195 | return false; |
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196 | } |
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197 | } |
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198 | |||
199 | /** |
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200 | * Allows the display and benchmarking of queries as they are being run |
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201 | * |
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202 | * @param string $sql Query to run, and single parameter to callback |
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203 | * @param callable $callback Callback to execute code |
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204 | * @param array $parameters Parameters for any parameterised query |
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205 | * @return mixed Result of query |
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206 | */ |
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207 | protected function benchmarkQuery($sql, $callback, $parameters = array()) |
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208 | { |
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209 | if (isset($_REQUEST['showqueries']) && Director::isDev()) { |
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210 | $this->queryCount++; |
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211 | $starttime = microtime(true); |
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212 | $result = $callback($sql); |
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213 | $endtime = round(microtime(true) - $starttime, 4); |
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214 | // replace parameters as closely as possible to what we'd expect the DB to put in |
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215 | if (strtolower($_REQUEST['showqueries']) == 'inline') { |
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216 | $sql = DB::inline_parameters($sql, $parameters); |
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217 | } |
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218 | $queryCount = sprintf("%04d", $this->queryCount); |
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219 | Debug::message("\n$queryCount: $sql\n{$endtime}s\n", false); |
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220 | return $result; |
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221 | } else { |
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222 | return $callback($sql); |
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223 | } |
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224 | } |
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225 | |||
226 | /** |
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227 | * Get the autogenerated ID from the previous INSERT query. |
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228 | * |
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229 | * @param string $table The name of the table to get the generated ID for |
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230 | * @return integer the most recently generated ID for the specified table |
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231 | */ |
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232 | public function getGeneratedID($table) |
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233 | { |
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234 | return $this->connector->getGeneratedID($table); |
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235 | } |
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236 | |||
237 | /** |
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238 | * Determines if we are connected to a server AND have a valid database |
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239 | * selected. |
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240 | * |
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241 | * @return boolean Flag indicating that a valid database is connected |
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242 | */ |
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243 | public function isActive() |
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244 | { |
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245 | return $this->connector->isActive(); |
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246 | } |
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247 | |||
248 | /** |
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249 | * Returns an escaped string. This string won't be quoted, so would be suitable |
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250 | * for appending to other quoted strings. |
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251 | * |
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252 | * @param mixed $value Value to be prepared for database query |
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253 | * @return string Prepared string |
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254 | */ |
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255 | public function escapeString($value) |
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256 | { |
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257 | return $this->connector->escapeString($value); |
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258 | } |
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259 | |||
260 | /** |
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261 | * Wrap a string into DB-specific quotes. |
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262 | * |
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263 | * @param mixed $value Value to be prepared for database query |
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264 | * @return string Prepared string |
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265 | */ |
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266 | public function quoteString($value) |
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267 | { |
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268 | return $this->connector->quoteString($value); |
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269 | } |
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270 | |||
271 | /** |
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272 | * Escapes an identifier (table / database name). Typically the value |
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273 | * is simply double quoted. Don't pass in already escaped identifiers in, |
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274 | * as this will double escape the value! |
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275 | * |
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276 | * @param string|array $value The identifier to escape or list of split components |
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277 | * @param string $separator Splitter for each component |
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278 | * @return string |
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279 | */ |
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280 | public function escapeIdentifier($value, $separator = '.') |
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281 | { |
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282 | // Split string into components |
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283 | if (!is_array($value)) { |
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284 | $value = explode($separator, $value); |
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285 | } |
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286 | |||
287 | // Implode quoted column |
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288 | return '"' . implode('"' . $separator . '"', $value) . '"'; |
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289 | } |
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290 | |||
291 | /** |
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292 | * Escapes unquoted columns keys in an associative array |
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293 | * |
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294 | * @param array $fieldValues |
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295 | * @return array List of field values with the keys as escaped column names |
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296 | */ |
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297 | protected function escapeColumnKeys($fieldValues) |
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298 | { |
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299 | $out = array(); |
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300 | foreach ($fieldValues as $field => $value) { |
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301 | $out[$this->escapeIdentifier($field)] = $value; |
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302 | } |
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303 | return $out; |
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304 | } |
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305 | |||
306 | /** |
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307 | * Execute a complex manipulation on the database. |
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308 | * A manipulation is an array of insert / or update sequences. The keys of the array are table names, |
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309 | * and the values are map containing 'command' and 'fields'. Command should be 'insert' or 'update', |
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310 | * and fields should be a map of field names to field values, NOT including quotes. |
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311 | * |
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312 | * The field values could also be in paramaterised format, such as |
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313 | * array('MAX(?,?)' => array(42, 69)), allowing the use of raw SQL values such as |
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314 | * array('NOW()' => array()). |
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315 | * |
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316 | * @see SQLWriteExpression::addAssignments for syntax examples |
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317 | * |
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318 | * @param array $manipulation |
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319 | */ |
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320 | public function manipulate($manipulation) |
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321 | { |
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322 | if (empty($manipulation)) { |
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323 | return; |
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324 | } |
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325 | |||
326 | foreach ($manipulation as $table => $writeInfo) { |
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327 | if (empty($writeInfo['fields'])) { |
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328 | continue; |
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329 | } |
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330 | // Note: keys of $fieldValues are not escaped |
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331 | $fieldValues = $writeInfo['fields']; |
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332 | |||
333 | // Switch command type |
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334 | switch ($writeInfo['command']) { |
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335 | case "update": |
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336 | // Build update |
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337 | $query = new SQLUpdate("\"$table\"", $this->escapeColumnKeys($fieldValues)); |
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338 | |||
339 | // Set best condition to use |
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340 | if (!empty($writeInfo['where'])) { |
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341 | $query->addWhere($writeInfo['where']); |
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342 | } elseif (!empty($writeInfo['id'])) { |
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343 | $query->addWhere(array('"ID"' => $writeInfo['id'])); |
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344 | } |
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345 | |||
346 | // Test to see if this update query shouldn't, in fact, be an insert |
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347 | if ($query->toSelect()->count()) { |
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348 | $query->execute(); |
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349 | break; |
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350 | } |
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351 | // ...if not, we'll skip on to the insert code |
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352 | |||
353 | case "insert": |
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354 | // Ensure that the ID clause is given if possible |
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355 | if (!isset($fieldValues['ID']) && isset($writeInfo['id'])) { |
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356 | $fieldValues['ID'] = $writeInfo['id']; |
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357 | } |
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358 | |||
359 | // Build insert |
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360 | $query = new SQLInsert("\"$table\"", $this->escapeColumnKeys($fieldValues)); |
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361 | |||
362 | $query->execute(); |
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363 | break; |
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364 | |||
365 | default: |
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366 | user_error( |
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367 | "SS_Database::manipulate() Can't recognise command '{$writeInfo['command']}'", |
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368 | E_USER_ERROR |
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369 | ); |
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370 | } |
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371 | } |
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372 | } |
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373 | |||
374 | /** |
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375 | * Enable supression of database messages. |
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376 | */ |
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377 | public function quiet() |
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378 | { |
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379 | $this->schemaManager->quiet(); |
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380 | } |
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381 | |||
382 | /** |
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383 | * Clear all data out of the database |
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384 | */ |
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385 | public function clearAllData() |
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390 | } |
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391 | } |
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392 | |||
393 | /** |
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394 | * Clear all data in a given table |
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395 | * |
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396 | * @param string $table Name of table |
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397 | */ |
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398 | public function clearTable($table) |
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399 | { |
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400 | $this->query("TRUNCATE \"$table\""); |
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401 | } |
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402 | |||
403 | /** |
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404 | * Generates a WHERE clause for null comparison check |
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405 | * |
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406 | * @param string $field Quoted field name |
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407 | * @param bool $isNull Whether to check for NULL or NOT NULL |
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408 | * @return string Non-parameterised null comparison clause |
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409 | */ |
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410 | public function nullCheckClause($field, $isNull) |
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411 | { |
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412 | $clause = $isNull |
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413 | ? "%s IS NULL" |
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414 | : "%s IS NOT NULL"; |
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415 | return sprintf($clause, $field); |
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416 | } |
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417 | |||
418 | /** |
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419 | * Generate a WHERE clause for text matching. |
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420 | * |
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421 | * @param String $field Quoted field name |
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422 | * @param String $value Escaped search. Can include percentage wildcards. |
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423 | * Ignored if $parameterised is true. |
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424 | * @param boolean $exact Exact matches or wildcard support. |
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425 | * @param boolean $negate Negate the clause. |
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426 | * @param boolean $caseSensitive Enforce case sensitivity if TRUE or FALSE. |
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427 | * Fallback to default collation if set to NULL. |
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428 | * @param boolean $parameterised Insert the ? placeholder rather than the |
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429 | * given value. If this is true then $value is ignored. |
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430 | * @return String SQL |
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431 | */ |
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432 | abstract public function comparisonClause( |
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433 | $field, |
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434 | $value, |
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435 | $exact = false, |
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436 | $negate = false, |
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437 | $caseSensitive = null, |
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438 | $parameterised = false |
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439 | ); |
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440 | |||
441 | /** |
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442 | * function to return an SQL datetime expression that can be used with the adapter in use |
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443 | * used for querying a datetime in a certain format |
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444 | * |
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445 | * @param string $date to be formated, can be either 'now', literal datetime like '1973-10-14 10:30:00' or |
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446 | * field name, e.g. '"SiteTree"."Created"' |
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447 | * @param string $format to be used, supported specifiers: |
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448 | * %Y = Year (four digits) |
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449 | * %m = Month (01..12) |
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450 | * %d = Day (01..31) |
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451 | * %H = Hour (00..23) |
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452 | * %i = Minutes (00..59) |
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453 | * %s = Seconds (00..59) |
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454 | * %U = unix timestamp, can only be used on it's own |
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455 | * @return string SQL datetime expression to query for a formatted datetime |
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456 | */ |
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457 | abstract public function formattedDatetimeClause($date, $format); |
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458 | |||
459 | /** |
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460 | * function to return an SQL datetime expression that can be used with the adapter in use |
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461 | * used for querying a datetime addition |
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462 | * |
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463 | * @param string $date, can be either 'now', literal datetime like '1973-10-14 10:30:00' or field name, |
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464 | * e.g. '"SiteTree"."Created"' |
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465 | * @param string $interval to be added, use the format [sign][integer] [qualifier], e.g. -1 Day, +15 minutes, |
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466 | * +1 YEAR |
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467 | * supported qualifiers: |
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468 | * - years |
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469 | * - months |
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470 | * - days |
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471 | * - hours |
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472 | * - minutes |
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473 | * - seconds |
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474 | * This includes the singular forms as well |
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475 | * @return string SQL datetime expression to query for a datetime (YYYY-MM-DD hh:mm:ss) which is the result of |
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476 | * the addition |
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477 | */ |
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478 | abstract public function datetimeIntervalClause($date, $interval); |
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479 | |||
480 | /** |
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481 | * function to return an SQL datetime expression that can be used with the adapter in use |
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482 | * used for querying a datetime substraction |
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483 | * |
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484 | * @param string $date1, can be either 'now', literal datetime like '1973-10-14 10:30:00' or field name |
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485 | * e.g. '"SiteTree"."Created"' |
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486 | * @param string $date2 to be substracted of $date1, can be either 'now', literal datetime |
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487 | * like '1973-10-14 10:30:00' or field name, e.g. '"SiteTree"."Created"' |
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488 | * @return string SQL datetime expression to query for the interval between $date1 and $date2 in seconds which |
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489 | * is the result of the substraction |
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490 | */ |
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491 | abstract public function datetimeDifferenceClause($date1, $date2); |
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492 | |||
493 | /** |
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494 | * String operator for concatenation of strings |
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495 | * |
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496 | * @return string |
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497 | */ |
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498 | public function concatOperator() |
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499 | { |
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500 | // @todo Make ' + ' in mssql |
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501 | return ' || '; |
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502 | } |
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503 | |||
504 | /** |
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505 | * Returns true if this database supports collations |
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506 | * |
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507 | * @return boolean |
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508 | */ |
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509 | abstract public function supportsCollations(); |
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510 | |||
511 | /** |
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512 | * Can the database override timezone as a connection setting, |
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513 | * or does it use the system timezone exclusively? |
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514 | * |
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515 | * @return Boolean |
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516 | */ |
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517 | abstract public function supportsTimezoneOverride(); |
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518 | |||
519 | /** |
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520 | * Query for the version of the currently connected database |
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521 | * @return string Version of this database |
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522 | */ |
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523 | public function getVersion() |
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526 | } |
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527 | |||
528 | /** |
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529 | * Get the database server type (e.g. mysql, postgresql). |
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530 | * This value is passed to the connector as the 'driver' argument when |
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531 | * initiating a database connection |
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532 | * |
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533 | * @return string |
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534 | */ |
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535 | abstract public function getDatabaseServer(); |
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536 | |||
537 | /** |
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538 | * Return the number of rows affected by the previous operation. |
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539 | * @return int |
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540 | */ |
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541 | public function affectedRows() |
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542 | { |
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543 | return $this->connector->affectedRows(); |
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544 | } |
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545 | |||
546 | /** |
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547 | * The core search engine, used by this class and its subclasses to do fun stuff. |
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548 | * Searches both SiteTree and File. |
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549 | * |
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550 | * @param array $classesToSearch List of classes to search |
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551 | * @param string $keywords Keywords as a string. |
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552 | * @param integer $start Item to start returning results from |
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553 | * @param integer $pageLength Number of items per page |
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554 | * @param string $sortBy Sort order expression |
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555 | * @param string $extraFilter Additional filter |
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556 | * @param boolean $booleanSearch Flag for boolean search mode |
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557 | * @param string $alternativeFileFilter |
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558 | * @param boolean $invertedMatch |
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559 | * @return PaginatedList Search results |
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560 | */ |
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561 | abstract public function searchEngine( |
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562 | $classesToSearch, |
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563 | $keywords, |
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564 | $start, |
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565 | $pageLength, |
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566 | $sortBy = "Relevance DESC", |
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567 | $extraFilter = "", |
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568 | $booleanSearch = false, |
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569 | $alternativeFileFilter = "", |
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570 | $invertedMatch = false |
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571 | ); |
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572 | |||
573 | /** |
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574 | * Determines if this database supports transactions |
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575 | * |
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576 | * @return boolean Flag indicating support for transactions |
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577 | */ |
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578 | abstract public function supportsTransactions(); |
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579 | |||
580 | /** |
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581 | * Invoke $callback within a transaction |
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582 | * |
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583 | * @param callable $callback Callback to run |
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584 | * @param callable $errorCallback Optional callback to run after rolling back transaction. |
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585 | * @param bool|string $transactionMode Optional transaction mode to use |
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586 | * @param bool $errorIfTransactionsUnsupported If true, this method will fail if transactions are unsupported. |
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587 | * Otherwise, the $callback will potentially be invoked outside of a transaction. |
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588 | * @throws Exception |
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589 | */ |
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590 | public function withTransaction( |
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616 | } |
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617 | } |
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618 | |||
619 | /* |
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620 | * Determines if the current database connection supports a given list of extensions |
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621 | * |
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622 | * @param array $extensions List of extensions to check for support of. The key of this array |
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623 | * will be an extension name, and the value the configuration for that extension. This |
||
624 | * could be one of partitions, tablespaces, or clustering |
||
625 | * @return boolean Flag indicating support for all of the above |
||
626 | * @todo Write test cases |
||
627 | */ |
||
628 | public function supportsExtensions($extensions) |
||
631 | } |
||
632 | |||
633 | /** |
||
634 | * Start a prepared transaction |
||
635 | * See http://developer.postgresql.org/pgdocs/postgres/sql-set-transaction.html for details on |
||
636 | * transaction isolation options |
||
637 | * |
||
638 | * @param string|boolean $transactionMode Transaction mode, or false to ignore |
||
639 | * @param string|boolean $sessionCharacteristics Session characteristics, or false to ignore |
||
640 | */ |
||
641 | abstract public function transactionStart($transactionMode = false, $sessionCharacteristics = false); |
||
642 | |||
643 | /** |
||
644 | * Create a savepoint that you can jump back to if you encounter problems |
||
645 | * |
||
646 | * @param string $savepoint Name of savepoint |
||
647 | */ |
||
648 | abstract public function transactionSavepoint($savepoint); |
||
649 | |||
650 | /** |
||
651 | * Rollback or revert to a savepoint if your queries encounter problems |
||
652 | * If you encounter a problem at any point during a transaction, you may |
||
653 | * need to rollback that particular query, or return to a savepoint |
||
654 | * |
||
655 | * @param string|boolean $savepoint Name of savepoint, or leave empty to rollback |
||
656 | * to last savepoint |
||
657 | * @return bool|null Boolean is returned if success state is known, or null if |
||
658 | * unknown. Note: For error checking purposes null should not be treated as error. |
||
659 | */ |
||
660 | abstract public function transactionRollback($savepoint = false); |
||
661 | |||
662 | /** |
||
663 | * Commit everything inside this transaction so far |
||
664 | * |
||
665 | * @param bool $chain |
||
666 | * @return bool|null Boolean is returned if success state is known, or null if |
||
667 | * unknown. Note: For error checking purposes null should not be treated as error. |
||
668 | */ |
||
669 | abstract public function transactionEnd($chain = false); |
||
670 | |||
671 | /** |
||
672 | * Return depth of current transaction |
||
673 | * |
||
674 | * @return int Nesting level, or 0 if not in a transaction |
||
675 | */ |
||
676 | public function transactionDepth() |
||
677 | { |
||
678 | // Placeholder error for transactional DBs that don't expose depth |
||
679 | if (!$this->supportsTransactions()) { |
||
680 | user_error(get_class($this) . " does not support transactionDepth", E_USER_WARNING); |
||
681 | } |
||
682 | return 0; |
||
683 | } |
||
684 | |||
685 | /** |
||
686 | * Determines if the used database supports application-level locks, |
||
687 | * which is different from table- or row-level locking. |
||
688 | * See {@link getLock()} for details. |
||
689 | * |
||
690 | * @return bool Flag indicating that locking is available |
||
691 | */ |
||
692 | public function supportsLocks() |
||
693 | { |
||
694 | return false; |
||
695 | } |
||
696 | |||
697 | /** |
||
698 | * Returns if the lock is available. |
||
699 | * See {@link supportsLocks()} to check if locking is generally supported. |
||
700 | * |
||
701 | * @param string $name Name of the lock |
||
702 | * @return bool |
||
703 | */ |
||
704 | public function canLock($name) |
||
705 | { |
||
706 | return false; |
||
707 | } |
||
708 | |||
709 | /** |
||
710 | * Sets an application-level lock so that no two processes can run at the same time, |
||
711 | * also called a "cooperative advisory lock". |
||
712 | * |
||
713 | * Return FALSE if acquiring the lock fails; otherwise return TRUE, if lock was acquired successfully. |
||
714 | * Lock is automatically released if connection to the database is broken (either normally or abnormally), |
||
715 | * making it less prone to deadlocks than session- or file-based locks. |
||
716 | * Should be accompanied by a {@link releaseLock()} call after the logic requiring the lock has completed. |
||
717 | * Can be called multiple times, in which case locks "stack" (PostgreSQL, SQL Server), |
||
718 | * or auto-releases the previous lock (MySQL). |
||
719 | * |
||
720 | * Note that this might trigger the database to wait for the lock to be released, delaying further execution. |
||
721 | * |
||
722 | * @param string $name Name of lock |
||
723 | * @param integer $timeout Timeout in seconds |
||
724 | * @return bool |
||
725 | */ |
||
726 | public function getLock($name, $timeout = 5) |
||
727 | { |
||
728 | return false; |
||
729 | } |
||
730 | |||
731 | /** |
||
732 | * Remove an application-level lock file to allow another process to run |
||
733 | * (if the execution aborts (e.g. due to an error) all locks are automatically released). |
||
734 | * |
||
735 | * @param string $name Name of the lock |
||
736 | * @return bool Flag indicating whether the lock was successfully released |
||
737 | */ |
||
738 | public function releaseLock($name) |
||
739 | { |
||
740 | return false; |
||
741 | } |
||
742 | |||
743 | /** |
||
744 | * Instruct the database to generate a live connection |
||
745 | * |
||
746 | * @param array $parameters An map of parameters, which should include: |
||
747 | * - server: The server, eg, localhost |
||
748 | * - username: The username to log on with |
||
749 | * - password: The password to log on with |
||
750 | * - database: The database to connect to |
||
751 | * - charset: The character set to use. Defaults to utf8 |
||
752 | * - timezone: (optional) The timezone offset. For example: +12:00, "Pacific/Auckland", or "SYSTEM" |
||
753 | * - driver: (optional) Driver name |
||
754 | */ |
||
755 | public function connect($parameters) |
||
756 | { |
||
757 | // Ensure that driver is available (required by PDO) |
||
758 | if (empty($parameters['driver'])) { |
||
759 | $parameters['driver'] = $this->getDatabaseServer(); |
||
760 | } |
||
761 | |||
762 | // Notify connector of parameters |
||
763 | $this->connector->connect($parameters); |
||
764 | |||
765 | // SS_Database subclass maintains responsibility for selecting database |
||
766 | // once connected in order to correctly handle schema queries about |
||
767 | // existence of database, error handling at the correct level, etc |
||
768 | if (!empty($parameters['database'])) { |
||
769 | $this->selectDatabase($parameters['database'], false, false); |
||
770 | } |
||
771 | } |
||
772 | |||
773 | /** |
||
774 | * Determine if the database with the specified name exists |
||
775 | * |
||
776 | * @param string $name Name of the database to check for |
||
777 | * @return bool Flag indicating whether this database exists |
||
778 | */ |
||
779 | public function databaseExists($name) |
||
782 | } |
||
783 | |||
784 | /** |
||
785 | * Retrieves the list of all databases the user has access to |
||
786 | * |
||
787 | * @return array List of database names |
||
788 | */ |
||
789 | public function databaseList() |
||
792 | } |
||
793 | |||
794 | /** |
||
795 | * Change the connection to the specified database, optionally creating the |
||
796 | * database if it doesn't exist in the current schema. |
||
797 | * |
||
798 | * @param string $name Name of the database |
||
799 | * @param bool $create Flag indicating whether the database should be created |
||
800 | * if it doesn't exist. If $create is false and the database doesn't exist |
||
801 | * then an error will be raised |
||
802 | * @param int|bool $errorLevel The level of error reporting to enable for the query, or false if no error |
||
803 | * should be raised |
||
804 | * @return bool Flag indicating success |
||
805 | */ |
||
806 | public function selectDatabase($name, $create = false, $errorLevel = E_USER_ERROR) |
||
807 | { |
||
808 | // In case our live environment is locked down, we can bypass a SHOW DATABASE check |
||
809 | $canConnect = Config::inst()->get(static::class, 'optimistic_connect') |
||
810 | || $this->schemaManager->databaseExists($name); |
||
811 | if ($canConnect) { |
||
812 | return $this->connector->selectDatabase($name); |
||
813 | } |
||
814 | |||
815 | // Check DB creation permisson |
||
816 | if (!$create) { |
||
817 | if ($errorLevel !== false) { |
||
818 | user_error("Attempted to connect to non-existing database \"$name\"", $errorLevel); |
||
819 | } |
||
820 | // Unselect database |
||
821 | $this->connector->unloadDatabase(); |
||
822 | return false; |
||
823 | } |
||
824 | $this->schemaManager->createDatabase($name); |
||
825 | return $this->connector->selectDatabase($name); |
||
826 | } |
||
827 | |||
828 | /** |
||
829 | * Drop the database that this object is currently connected to. |
||
830 | * Use with caution. |
||
831 | */ |
||
832 | public function dropSelectedDatabase() |
||
833 | { |
||
834 | $databaseName = $this->connector->getSelectedDatabase(); |
||
835 | if ($databaseName) { |
||
836 | $this->connector->unloadDatabase(); |
||
837 | $this->schemaManager->dropDatabase($databaseName); |
||
838 | } |
||
839 | } |
||
840 | |||
841 | /** |
||
842 | * Returns the name of the currently selected database |
||
843 | * |
||
844 | * @return string|null Name of the selected database, or null if none selected |
||
845 | */ |
||
846 | public function getSelectedDatabase() |
||
849 | } |
||
850 | |||
851 | /** |
||
852 | * Return SQL expression used to represent the current date/time |
||
853 | * |
||
854 | * @return string Expression for the current date/time |
||
855 | */ |
||
856 | abstract public function now(); |
||
857 | |||
858 | /** |
||
859 | * Returns the database-specific version of the random() function |
||
860 | * |
||
861 | * @return string Expression for a random value |
||
862 | */ |
||
863 | abstract public function random(); |
||
864 | } |
||
865 |