+ /**
+ * @brief Insert a row into a table
+ *
+ * @param string $table Table name
+ * @param array $param parameter array
+ *
+ * @return boolean was the insert successfull?
+ */
+ static public function insert($table, $param) {
+ $sql = "INSERT INTO `".self::$dbo->escape($table)."` (`".implode("`, `", array_keys($param))."`) VALUES (".
+ substr(str_repeat("?, ", count($param)), 0, -2).");";
+
+ return self::e($sql, $param);
+ }
+
+ /**
+ * @brief Starts a transaction
+ *
+ * @return boolean Was the command executed successfully?
+ */
+ static public function transaction() {
+ if (!self::e('COMMIT')) {
+ return false;
+ }
+ if (!self::e('START TRANSACTION')) {
+ return false;
+ }
+ self::$in_transaction = true;
+ return true;
+ }
+
+ /**
+ * @brief Does a commit
+ *
+ * @return boolean Was the command executed successfully?
+ */
+ static public function commit() {
+ if (!self::e('COMMIT')) {
+ return false;
+ }
+ self::$in_transaction = false;
+ return true;
+ }
+
+ /**
+ * @brief Does a rollback
+ *
+ * @return boolean Was the command executed successfully?
+ */
+ static public function rollback() {
+ if (!self::e('ROLLBACK')) {
+ return false;
+ }
+ self::$in_transaction = false;
+ return true;
+ }
+
+ /**
+ * @brief Build the array with the table relations
+ *
+ * The array is build from the database definitions in dbstructure.php
+ *
+ * This process must only be started once, since the value is cached.
+ */
+ static private function build_relation_data() {
+ $definition = db_definition();
+
+ foreach ($definition AS $table => $structure) {
+ foreach ($structure['fields'] AS $field => $field_struct) {
+ if (isset($field_struct['relation'])) {
+ foreach ($field_struct['relation'] AS $rel_table => $rel_field) {
+ self::$relation[$rel_table][$rel_field][$table][] = $field;
+ }
+ }
+ }
+ }
+ }
+
+ /**
+ * @brief Delete a row from a table
+ *
+ * @param string $table Table name
+ * @param array $param parameter array
+ * @param boolean $in_process Internal use: Only do a commit after the last delete
+ * @param array $callstack Internal use: prevent endless loops
+ *
+ * @return boolean|array was the delete successfull? When $in_process is set: deletion data
+ */
+ static public function delete($table, $param, $in_process = false, &$callstack = array()) {
+
+ $commands = array();
+
+ // Create a key for the loop prevention
+ $key = $table.':'.implode(':', array_keys($param)).':'.implode(':', $param);
+
+ // We quit when this key already exists in the callstack.
+ if (isset($callstack[$key])) {
+ return $commands;
+ }
+
+ $callstack[$key] = true;
+
+ $table = self::$dbo->escape($table);
+
+ $commands[$key] = array('table' => $table, 'param' => $param);
+
+ // To speed up the whole process we cache the table relations
+ if (count(self::$relation) == 0) {
+ self::build_relation_data();
+ }
+
+ // Is there a relation entry for the table?
+ if (isset(self::$relation[$table])) {
+ // We only allow a simple "one field" relation.
+ $field = array_keys(self::$relation[$table])[0];
+ $rel_def = array_values(self::$relation[$table])[0];
+
+ // Create a key for preventing double queries
+ $qkey = $field.'-'.$table.':'.implode(':', array_keys($param)).':'.implode(':', $param);
+
+ // When the search field is the relation field, we don't need to fetch the rows
+ // This is useful when the leading record is already deleted in the frontend but the rest is done in the backend
+ if ((count($param) == 1) AND ($field == array_keys($param)[0])) {
+ foreach ($rel_def AS $rel_table => $rel_fields) {
+ foreach ($rel_fields AS $rel_field) {
+ $retval = self::delete($rel_table, array($rel_field => array_values($param)[0]), true, $callstack);
+ $commands = array_merge($commands, $retval);
+ }
+ }
+ // We quit when this key already exists in the callstack.
+ } elseif (!isset($callstack[$qkey])) {
+
+ $callstack[$qkey] = true;
+
+ // Fetch all rows that are to be deleted
+ $sql = "SELECT ".self::$dbo->escape($field)." FROM `".$table."` WHERE `".
+ implode("` = ? AND `", array_keys($param))."` = ?";
+
+ $data = self::p($sql, $param);
+ while ($row = self::fetch($data)) {
+ // Now we accumulate the delete commands
+ $retval = self::delete($table, array($field => $row[$field]), true, $callstack);
+ $commands = array_merge($commands, $retval);
+ }
+
+ // Since we had split the delete command we don't need the original command anymore
+ unset($commands[$key]);
+ }
+ }
+
+ if (!$in_process) {
+ // Now we finalize the process
+ $do_transaction = !self::$in_transaction;
+
+ if ($do_transaction) {
+ self::transaction();
+ }
+
+ $compacted = array();
+ $counter = array();
+ foreach ($commands AS $command) {
+ if (count($command['param']) > 1) {
+ $sql = "DELETE FROM `".$command['table']."` WHERE `".
+ implode("` = ? AND `", array_keys($command['param']))."` = ?";
+
+ logger(dba::replace_parameters($sql, $command['param']), LOGGER_DATA);
+
+ if (!self::e($sql, $command['param'])) {
+ if ($do_transaction) {
+ self::rollback();
+ }
+ return false;
+ }
+ } else {
+ $key_table = $command['table'];
+ $key_param = array_keys($command['param'])[0];
+ $value = array_values($command['param'])[0];
+
+ // Split the SQL queries in chunks of 100 values
+ // We do the $i stuff here to make the code better readable
+ $i = $counter[$key_table][$key_param];
+ if (count($compacted[$key_table][$key_param][$i]) > 100) {
+ ++$i;
+ }
+
+ $compacted[$key_table][$key_param][$i][$value] = $value;
+ $counter[$key_table][$key_param] = $i;
+ }
+ }
+ foreach ($compacted AS $table => $values) {
+ foreach ($values AS $field => $field_value_list) {
+ foreach ($field_value_list AS $field_values) {
+ $sql = "DELETE FROM `".$table."` WHERE `".$field."` IN (".
+ substr(str_repeat("?, ", count($field_values)), 0, -2).");";
+
+ logger(dba::replace_parameters($sql, $field_values), LOGGER_DATA);
+
+ if (!self::e($sql, $field_values)) {
+ if ($do_transaction) {
+ self::rollback();
+ }
+ return false;
+ }
+ }
+ }
+ }
+ if ($do_transaction) {
+ self::commit();
+ }
+ return true;
+ }
+
+ return $commands;
+ }
+
+ /**
+ * @brief Updates rows
+ *
+ * Updates rows in the database. When $old_fields is set to an array,
+ * the system will only do an update if the fields in that array changed.
+ *
+ * Attention:
+ * Only the values in $old_fields are compared.
+ * This is an intentional behaviour.
+ *
+ * Example:
+ * We include the timestamp field in $fields but not in $old_fields.
+ * Then the row will only get the new timestamp when the other fields had changed.
+ *
+ * When $old_fields is set to a boolean value the system will do this compare itself.
+ * When $old_fields is set to "true" the system will do an insert if the row doesn't exists.
+ *
+ * Attention:
+ * Only set $old_fields to a boolean value when you are sure that you will update a single row.
+ * When you set $old_fields to "true" then $fields must contain all relevant fields!
+ *
+ * @param string $table Table name
+ * @param array $fields contains the fields that are updated
+ * @param array $condition condition array with the key values
+ * @param array|boolean $old_fields array with the old field values that are about to be replaced
+ *
+ * @return boolean was the update successfull?
+ */
+ static public function update($table, $fields, $condition, $old_fields = array()) {
+
+ /** @todo We may use MySQL specific functions here:
+ * INSERT INTO `config` (`cat`, `k`, `v`) VALUES ('%s', '%s', '%s') ON DUPLICATE KEY UPDATE `v` = '%s'"
+ * But I think that it doesn't make sense here.
+ */
+
+ $table = self::$dbo->escape($table);
+
+ if (is_bool($old_fields)) {
+ $sql = "SELECT * FROM `".$table."` WHERE `".
+ implode("` = ? AND `", array_keys($condition))."` = ? LIMIT 1";
+
+ $params = array();
+ foreach ($condition AS $value) {
+ $params[] = $value;
+ }
+
+ $do_insert = $old_fields;
+
+ $old_fields = self::fetch_first($sql, $params);
+ if (is_bool($old_fields)) {
+ if ($do_insert) {
+ return self::insert($table, $fields);
+ }
+ $old_fields = array();
+ }
+ }
+
+ $do_update = (count($old_fields) == 0);
+
+ foreach ($old_fields AS $fieldname => $content) {
+ if (isset($fields[$fieldname])) {
+ if ($fields[$fieldname] == $content) {
+ unset($fields[$fieldname]);
+ } else {
+ $do_update = true;
+ }
+ }
+ }
+
+ if (!$do_update OR (count($fields) == 0)) {
+ return true;
+ }
+
+ $sql = "UPDATE `".$table."` SET `".
+ implode("` = ?, `", array_keys($fields))."` = ? WHERE `".
+ implode("` = ? AND `", array_keys($condition))."` = ?";
+
+ $params = array();
+ foreach ($fields AS $value) {
+ $params[] = $value;
+ }
+ foreach ($condition AS $value) {
+ $params[] = $value;
+ }
+
+ return self::e($sql, $params);
+ }
+
+ /**
+ * @brief Select rows from a table
+ *
+ * @param string $table Table name
+ * @param array $fields array of selected fields
+ * @param array $condition array of fields for condition
+ * @param array $params array of several parameters
+ *
+ * @return boolean|object If "limit" is equal "1" only a single row is returned, else a query object is returned
+ *
+ * Example:
+ * $table = "item";
+ * $fields = array("id", "uri", "uid", "network");
+ * $condition = array("uid" => 1, "network" => 'dspr');
+ * $params = array("order" => array("id", "received" => true), "limit" => 1);
+ *
+ * $data = dba::select($table, $fields, $condition, $params);
+ */
+ static public function select($table, $fields = array(), $condition = array(), $params = array()) {
+ if ($table == '') {
+ return false;
+ }
+
+ if (count($fields) > 0) {
+ $select_fields = "`".implode("`, `", array_values($fields))."`";
+ } else {
+ $select_fields = "*";
+ }
+
+ if (count($condition) > 0) {
+ $condition_string = " WHERE `".implode("` = ? AND `", array_keys($condition))."` = ?";
+ } else {
+ $condition_string = "";
+ }
+
+ $param_string = '';
+ $single_row = false;
+
+ if (isset($params['order'])) {
+ $param_string .= " ORDER BY ";
+ foreach ($params['order'] AS $fields => $order) {
+ if (!is_int($fields)) {
+ $param_string .= "`".$fields."` ".($order ? "DESC" : "ASC").", ";
+ } else {
+ $param_string .= "`".$order."`, ";
+ }
+ }
+ $param_string = substr($param_string, 0, -2);
+ }
+
+ if (isset($params['limit'])) {
+ if (is_int($params['limit'])) {
+ $param_string .= " LIMIT ".$params['limit'];
+ $single_row =($params['limit'] == 1);
+ }
+ }
+
+ $sql = "SELECT ".$select_fields." FROM `".$table."`".$condition_string.$param_string;
+
+ $result = self::p($sql, $condition);
+
+ if (is_bool($result) OR !$single_row) {
+ return $result;
+ } else {
+ $row = self::fetch($result);
+ self::close($result);
+ return $row;
+ }
+ }
+
+ /**
+ * @brief Closes the current statement
+ *
+ * @param object $stmt statement object
+ * @return boolean was the close successfull?
+ */
+ static public function close($stmt) {
+ if (!is_object($stmt)) {
+ return false;
+ }
+
+ switch (self::$dbo->driver) {
+ case 'pdo':
+ return $stmt->closeCursor();
+ case 'mysqli':
+ return $stmt->free_result();
+ return $stmt->close();
+ case 'mysql':
+ return mysql_free_result($stmt);
+ }
+ }
+}
+