[1] | 1 | <?php |
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| 2 | /** |
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| 3 | * DB.inc.php |
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| 4 | * code by strangecode :: www.strangecode.com :: this document contains copyrighted information |
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| 5 | * |
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| 6 | * DB abstraction layer. |
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| 7 | * |
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| 8 | * @author Quinn Comendant <quinn@strangecode.com> |
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[15] | 9 | * @version 1.0.1 |
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[1] | 10 | */ |
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[42] | 11 | |
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[1] | 12 | class DB { |
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| 13 | |
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| 14 | // If DB::connect has successfully opened a db connection. |
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| 15 | var $_connected = false; |
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| 16 | |
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| 17 | // Database handler. |
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| 18 | var $dbh; |
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| 19 | |
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| 20 | // Hash of DB parameters. |
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| 21 | var $_params = array(); |
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| 22 | |
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| 23 | // Default parameters. |
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| 24 | var $_param_defaults = array( |
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| 25 | |
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| 26 | // DB passwords should be set as apache environment variables in httpd.conf, readable only by root. |
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| 27 | 'db_server' => 'localhost', |
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| 28 | 'db_name' => null, |
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| 29 | 'db_user' => null, |
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| 30 | 'db_pass' => null, |
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| 31 | |
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| 32 | // Debugging. |
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| 33 | 'db_always_debug' => false, // TRUE = display all SQL queries. |
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| 34 | 'db_debug' => false, // TRUE = display db errors. |
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| 35 | 'db_die_on_failure' => false, // TRUE = script stops on db error. |
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| 36 | ); |
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[42] | 37 | |
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[1] | 38 | // Translate between HTML and MySQL character set names. |
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| 39 | var $mysql_character_sets = array( |
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| 40 | 'utf-8' => 'utf8', |
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| 41 | 'iso-8859-1' => 'latin1', |
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| 42 | ); |
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[42] | 43 | |
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[1] | 44 | // Caches. |
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| 45 | var $existing_tables; |
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| 46 | var $table_columns; |
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[42] | 47 | |
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[1] | 48 | /** |
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| 49 | * This method enforces the singleton pattern for this class. |
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| 50 | * |
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| 51 | * @return object Reference to the global SessionCache object. |
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| 52 | * @access public |
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| 53 | * @static |
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| 54 | */ |
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| 55 | function &getInstance() |
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| 56 | { |
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| 57 | static $instance = null; |
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| 58 | |
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| 59 | if ($instance === null) { |
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| 60 | $instance = new DB(); |
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| 61 | } |
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| 62 | |
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| 63 | return $instance; |
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| 64 | } |
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[42] | 65 | |
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[1] | 66 | /** |
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| 67 | * Constructor. |
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| 68 | */ |
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| 69 | function DB() |
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| 70 | { |
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| 71 | // Initialize default params. |
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| 72 | if (isset($params) && is_array($params)) { |
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| 73 | // Merge new parameters with old overriding only those passed. |
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| 74 | $this->_params = array_merge($this->_params, $params); |
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| 75 | } |
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| 76 | } |
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| 77 | |
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| 78 | /** |
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| 79 | * Set (or overwrite existing) parameters by passing an array of new parameters. |
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| 80 | * |
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| 81 | * @access public |
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| 82 | * |
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| 83 | * @param array $params Array of parameters (key => val pairs). |
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| 84 | */ |
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| 85 | function setParam($params) |
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| 86 | { |
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[127] | 87 | $app =& App::getInstance(); |
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| 88 | |
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[119] | 89 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 90 | $_this =& DB::getInstance(); |
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[1] | 91 | } |
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| 92 | |
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| 93 | if (isset($params) && is_array($params)) { |
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| 94 | // Merge new parameters with old overriding only those passed. |
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[119] | 95 | $_this->_params = array_merge($_this->_params, $params); |
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[1] | 96 | } else { |
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[127] | 97 | $app->logMsg(sprintf('Parameters are not an array: %s', $params), LOG_ERR, __FILE__, __LINE__); |
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[1] | 98 | } |
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| 99 | } |
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| 100 | |
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| 101 | /** |
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| 102 | * Return the value of a parameter. |
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| 103 | * |
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| 104 | * @access public |
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| 105 | * |
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| 106 | * @param string $param The key of the parameter to return. |
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| 107 | * |
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| 108 | * @return mixed Parameter value. |
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| 109 | */ |
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| 110 | function getParam($param) |
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| 111 | { |
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[127] | 112 | $app =& App::getInstance(); |
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| 113 | |
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[119] | 114 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 115 | $_this =& DB::getInstance(); |
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[1] | 116 | } |
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| 117 | |
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[119] | 118 | if (isset($_this->_params[$param])) { |
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| 119 | return $_this->_params[$param]; |
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[1] | 120 | } else { |
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[127] | 121 | $app->logMsg(sprintf('Parameter is not set: %s', $param), LOG_DEBUG, __FILE__, __LINE__); |
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[1] | 122 | return null; |
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| 123 | } |
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| 124 | } |
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[42] | 125 | |
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[1] | 126 | /** |
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| 127 | * Connect to database with credentials in params. |
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| 128 | * |
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| 129 | * @access public |
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| 130 | * @author Quinn Comendant <quinn@strangecode.com> |
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| 131 | * @since 28 Aug 2005 14:02:49 |
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| 132 | */ |
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| 133 | function connect() |
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| 134 | { |
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[127] | 135 | $app =& App::getInstance(); |
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| 136 | |
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[119] | 137 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 138 | $_this =& DB::getInstance(); |
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[1] | 139 | } |
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[42] | 140 | |
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[119] | 141 | if (!$_this->getParam('db_name') || !$_this->getParam('db_user') || !$_this->getParam('db_pass')) { |
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[127] | 142 | $app->logMsg('Database credentials missing.', LOG_EMERG, __FILE__, __LINE__); |
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[1] | 143 | return false; |
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| 144 | } |
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[42] | 145 | |
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[1] | 146 | // Connect to database. Always create a new link to the server. |
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[119] | 147 | if ($_this->dbh = mysql_connect($_this->getParam('db_server'), $_this->getParam('db_user'), $_this->getParam('db_pass'), true)) { |
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[1] | 148 | // Select database |
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[119] | 149 | mysql_select_db($_this->getParam('db_name'), $_this->dbh); |
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[1] | 150 | } |
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[42] | 151 | |
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[15] | 152 | // Test for connection errors. |
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[119] | 153 | if (!$_this->dbh || mysql_error($_this->dbh)) { |
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| 154 | $mysql_error_msg = $_this->dbh ? 'Codebase MySQL error: (' . mysql_errno($_this->dbh) . ') ' . mysql_error($_this->dbh) : 'Codebase MySQL error: Could not connect to server.'; |
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[127] | 155 | $app->logMsg($mysql_error_msg, LOG_EMERG, __FILE__, __LINE__); |
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[15] | 156 | |
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| 157 | // Print helpful or pretty error? |
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[119] | 158 | if ($_this->getParam('db_debug')) { |
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[1] | 159 | echo $mysql_error_msg . "\n"; |
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| 160 | } else { |
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| 161 | echo _("This page is temporarily unavailable. It should be back up in a few minutes."); |
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| 162 | } |
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[15] | 163 | |
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| 164 | // Die or continue without connection? |
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[119] | 165 | if ($_this->getParam('db_die_on_failure')) { |
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[15] | 166 | echo "\n\n<!-- Script execution stopped out of embarrassment. -->"; |
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| 167 | die; |
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| 168 | } else { |
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| 169 | return false; |
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| 170 | } |
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[1] | 171 | } |
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[42] | 172 | |
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[1] | 173 | // DB connection success! |
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[119] | 174 | $_this->_connected = true; |
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[1] | 175 | |
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[10] | 176 | // Tell MySQL what character set we're useing. Available only on MySQL verions > 4.01.01. |
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[127] | 177 | $_this->query("/*!40101 SET NAMES '" . $_this->mysql_character_sets[strtolower($app->getParam('character_set'))] . "' */"); |
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[10] | 178 | |
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[1] | 179 | return true; |
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| 180 | } |
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[42] | 181 | |
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[1] | 182 | /** |
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| 183 | * Close db connection. |
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| 184 | * |
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| 185 | * @access public |
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| 186 | * @author Quinn Comendant <quinn@strangecode.com> |
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| 187 | * @since 28 Aug 2005 14:32:01 |
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| 188 | */ |
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| 189 | function close() |
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| 190 | { |
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[119] | 191 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 192 | $_this =& DB::getInstance(); |
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[1] | 193 | } |
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[42] | 194 | |
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[119] | 195 | if (!$_this->_connected) { |
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[1] | 196 | return false; |
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| 197 | } |
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| 198 | |
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[119] | 199 | mysql_close($_this->dbh); |
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[1] | 200 | } |
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[42] | 201 | |
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[1] | 202 | /** |
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| 203 | * Return the current database handler. |
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| 204 | * |
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| 205 | * @access public |
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| 206 | * @return resource Current value of $this->dbh. |
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| 207 | * @author Quinn Comendant <quinn@strangecode.com> |
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| 208 | * @since 20 Aug 2005 13:50:36 |
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| 209 | */ |
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| 210 | function getDBH() |
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| 211 | { |
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[119] | 212 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 213 | $_this =& DB::getInstance(); |
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[1] | 214 | } |
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[42] | 215 | |
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[119] | 216 | if (!$_this->_connected) { |
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[1] | 217 | return false; |
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| 218 | } |
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| 219 | |
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[119] | 220 | return $_this->dbh; |
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[1] | 221 | } |
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[42] | 222 | |
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[1] | 223 | /** |
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| 224 | * Returns connection status |
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| 225 | * |
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| 226 | * @access public |
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| 227 | * @author Quinn Comendant <quinn@strangecode.com> |
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| 228 | * @since 28 Aug 2005 14:58:09 |
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| 229 | */ |
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| 230 | function isConnected() |
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| 231 | { |
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| 232 | return $this->_connected; |
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| 233 | } |
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[71] | 234 | |
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| 235 | /** |
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| 236 | * Returns a properly escaped string using mysql_real_escape_string() with the current connection's charset. |
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| 237 | * |
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| 238 | * @access public |
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| 239 | * @param string $string Input string to be sent as SQL query. |
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| 240 | * @return string Escaped string from mysql_real_escape_string() |
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| 241 | * @author Quinn Comendant <quinn@strangecode.com> |
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| 242 | * @since 06 Mar 2006 16:41:32 |
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| 243 | */ |
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| 244 | function escapeString($string) |
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| 245 | { |
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[119] | 246 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 247 | $_this =& DB::getInstance(); |
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[71] | 248 | } |
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[119] | 249 | return mysql_real_escape_string($string, $_this->dbh); |
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[71] | 250 | } |
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[42] | 251 | |
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[1] | 252 | /** |
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| 253 | * A wrapper for mysql_query. Allows us to set the database link_identifier, |
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| 254 | * to trap errors and ease debugging. |
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| 255 | * |
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| 256 | * @param string $query The SQL query to execute |
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| 257 | * @param bool $debug If true, prints debugging info |
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| 258 | * @return resource Query identifier |
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| 259 | */ |
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| 260 | function query($query, $debug=false) |
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| 261 | { |
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[127] | 262 | $app =& App::getInstance(); |
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| 263 | |
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[1] | 264 | static $_query_count = 0; |
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[42] | 265 | |
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[119] | 266 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 267 | $_this =& DB::getInstance(); |
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[1] | 268 | } |
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[42] | 269 | |
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[119] | 270 | if (!$_this->_connected) { |
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[1] | 271 | return false; |
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| 272 | } |
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| 273 | |
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| 274 | $_query_count++; |
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| 275 | $debugqry = preg_replace("/\n[\t ]+/", "\n", $query); |
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[119] | 276 | if ($_this->getParam('db_always_debug') || $debug) { |
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[1] | 277 | echo "<!-- ----------------- Query $_query_count ---------------------\n$debugqry\n-->\n"; |
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| 278 | } |
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[42] | 279 | |
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[1] | 280 | // Execute! |
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[119] | 281 | $qid = mysql_query($query, $_this->dbh); |
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[42] | 282 | |
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[1] | 283 | // Error checking. |
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[119] | 284 | if (!$qid || mysql_error($_this->dbh)) { |
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| 285 | if ($_this->getParam('db_debug')) { |
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| 286 | echo '<pre style="padding:2em; background:#ddd; font:9px monaco;">' . wordwrap(mysql_error($_this->dbh)) . '<hr>' . htmlspecialchars($debugqry) . '</pre>'; |
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[1] | 287 | } else { |
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| 288 | echo _("This page is temporarily unavailable. It should be back up in a few minutes."); |
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| 289 | } |
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[127] | 290 | $app->logMsg(sprintf('MySQL error %s: %s in query: %s', mysql_errno($_this->dbh), mysql_error($_this->dbh), $debugqry), LOG_EMERG, __FILE__, __LINE__); |
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[119] | 291 | if ($_this->getParam('db_die_on_failure')) { |
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[1] | 292 | echo "\n\n<!-- Script execution stopped out of embarrassment. -->"; |
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| 293 | die; |
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| 294 | } |
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| 295 | } |
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[42] | 296 | |
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[1] | 297 | return $qid; |
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| 298 | } |
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| 299 | |
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| 300 | /** |
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[42] | 301 | * Loads a list of tables in the current database into an array, and returns |
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[1] | 302 | * true if the requested table is found. Use this function to enable/disable |
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[42] | 303 | * funtionality based upon the current available db tables or to dynamically |
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[1] | 304 | * create tables if missing. |
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| 305 | * |
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| 306 | * @param string $table The name of the table to search. |
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| 307 | * @param bool $strict Get fresh table info (in case DB changed). |
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| 308 | * @return bool true if given $table exists. |
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| 309 | */ |
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| 310 | function tableExists($table, $use_cached_results=true) |
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[42] | 311 | { |
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[127] | 312 | $app =& App::getInstance(); |
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| 313 | |
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[119] | 314 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 315 | $_this =& DB::getInstance(); |
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[1] | 316 | } |
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[42] | 317 | |
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[119] | 318 | if (!$_this->_connected) { |
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[1] | 319 | return false; |
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| 320 | } |
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| 321 | |
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[119] | 322 | if (!isset($_this->existing_tables) || !$use_cached_results) { |
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| 323 | $_this->existing_tables = array(); |
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| 324 | $qid = $_this->query("SHOW TABLES"); |
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[1] | 325 | while (list($row) = mysql_fetch_row($qid)) { |
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[119] | 326 | $_this->existing_tables[] = $row; |
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[1] | 327 | } |
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| 328 | } |
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[119] | 329 | if (in_array($table, $_this->existing_tables)) { |
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[1] | 330 | return true; |
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| 331 | } else { |
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[127] | 332 | $app->logMsg(sprintf('nonexistent DB table: %s.%s', $_this->getParam('db_name'), $table), LOG_ALERT, __FILE__, __LINE__); |
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[1] | 333 | return false; |
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| 334 | } |
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| 335 | } |
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[42] | 336 | |
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[1] | 337 | /** |
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| 338 | * Tests if the given array of columns exists in the specified table. |
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| 339 | * |
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| 340 | * @param string $table The name of the table to search. |
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| 341 | * @param array $columns An array of column names. |
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| 342 | * @param bool $strict Exact schema match, or are additional fields in the table okay? |
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| 343 | * @param bool $strict Get fresh table info (in case DB changed). |
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| 344 | * @return bool true if given $table exists. |
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| 345 | */ |
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| 346 | function columnExists($table, $columns, $strict=true, $use_cached_results=true) |
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[42] | 347 | { |
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[119] | 348 | if (!isset($_this) || !is_a($_this, 'DB') && !is_subclass_of($_this, 'DB')) { |
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| 349 | $_this =& DB::getInstance(); |
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[1] | 350 | } |
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[42] | 351 | |
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[119] | 352 | if (!$_this->_connected) { |
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[1] | 353 | return false; |
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| 354 | } |
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| 355 | |
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| 356 | // Ensure the table exists. |
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[119] | 357 | if (!$_this->tableExists($table, $use_cached_results)) { |
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[1] | 358 | return false; |
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| 359 | } |
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[42] | 360 | |
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[1] | 361 | // For single-value columns. |
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| 362 | if (!is_array($columns)) { |
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| 363 | $columns = array($columns); |
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| 364 | } |
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[42] | 365 | |
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[119] | 366 | if (!isset($_this->table_columns[$table]) || !$use_cached_results) { |
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[1] | 367 | // Populate and cache array of current columns for this table. |
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[119] | 368 | $_this->table_columns[$table] = array(); |
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| 369 | $qid = $_this->query("DESCRIBE $table"); |
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[1] | 370 | while ($row = mysql_fetch_row($qid)) { |
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[119] | 371 | $_this->table_columns[$table][] = $row[0]; |
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[1] | 372 | } |
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| 373 | } |
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[42] | 374 | |
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[1] | 375 | if ($strict) { |
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| 376 | // Do an exact comparison of table schemas. |
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| 377 | sort($columns); |
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[119] | 378 | sort($_this->table_columns[$table]); |
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| 379 | return $_this->table_columns[$table] == $columns; |
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[1] | 380 | } else { |
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| 381 | // Only check that the specified columns are available in the table. |
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[119] | 382 | $match_columns = array_intersect($_this->table_columns[$table], $columns); |
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[1] | 383 | sort($columns); |
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| 384 | sort($match_columns); |
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| 385 | return $match_columns == $columns; |
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| 386 | } |
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| 387 | } |
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[42] | 388 | |
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[1] | 389 | /** |
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| 390 | * Reset cached items. |
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| 391 | * |
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| 392 | * @access public |
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| 393 | * @author Quinn Comendant <quinn@strangecode.com> |
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| 394 | * @since 28 Aug 2005 22:10:50 |
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| 395 | */ |
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| 396 | function resetCache() |
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| 397 | { |
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| 398 | $this->existing_tables = null; |
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| 399 | $this->table_columns = null; |
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| 400 | } |
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[42] | 401 | |
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[1] | 402 | } // End. |
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| 403 | |
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| 404 | ?> |
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