电脑维修店管理系统包含四个参与者，即客户、渠道、员工和支付网关（Paypal）。它提供了管理维修请求报价、管理维修状态、.zip

<?php /** * CodeIgniter * * An open source application development framework for PHP * * This content is released under the MIT License (MIT) * * Copyright (c) 2014 - 2019, British Columbia Institute of Technology * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * * @package CodeIgniter * @author EllisLab Dev Team * @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/) * @copyright Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/) * @license https://opensource.org/licenses/MIT MIT License * @link https://codeigniter.com * @since Version 1.0.0 * @filesource */ defined('BASEPATH') OR exit('No direct script access allowed'); /** * Query Builder Class * * This is the platform-independent base Query Builder implementation class. * * @package CodeIgniter * @subpackage Drivers * @category Database * @author EllisLab Dev Team * @link https://codeigniter.com/user_guide/database/ */ abstract class CI_DB_query_builder extends CI_DB_driver { /** * Return DELETE SQL flag * * @var bool */ protected $return_delete_sql = FALSE; /** * Reset DELETE data flag * * @var bool */ protected $reset_delete_data = FALSE; /** * QB SELECT data * * @var array */ protected $qb_select = array(); /** * QB DISTINCT flag * * @var bool */ protected $qb_distinct = FALSE; /** * QB FROM data * * @var array */ protected $qb_from = array(); /** * QB JOIN data * * @var array */ protected $qb_join = array(); /** * QB WHERE data * * @var array */ protected $qb_where = array(); /** * QB GROUP BY data * * @var array */ protected $qb_groupby = array(); /** * QB HAVING data * * @var array */ protected $qb_having = array(); /** * QB keys * * @var array */ protected $qb_keys = array(); /** * QB LIMIT data * * @var int */ protected $qb_limit = FALSE; /** * QB OFFSET data * * @var int */ protected $qb_offset = FALSE; /** * QB ORDER BY data * * @var array */ protected $qb_orderby = array(); /** * QB data sets * * @var array */ protected $qb_set = array(); /** * QB data set for update_batch() * * @var array */ protected $qb_set_ub = array(); /** * QB aliased tables list * * @var array */ protected $qb_aliased_tables = array(); /** * QB WHERE group started flag * * @var bool */ protected $qb_where_group_started = FALSE; /** * QB WHERE group count * * @var int */ protected $qb_where_group_count = 0; // Query Builder Caching variables /** * QB Caching flag * * @var bool */ protected $qb_caching = FALSE; /** * QB Cache exists list * * @var array */ protected $qb_cache_exists = array(); /** * QB Cache SELECT data * * @var array */ protected $qb_cache_select = array(); /** * QB Cache FROM data * * @var array */ protected $qb_cache_from = array(); /** * QB Cache JOIN data * * @var array */ protected $qb_cache_join = array(); /** * QB Cache aliased tables list * * @var array */ protected $qb_cache_aliased_tables = array(); /** * QB Cache WHERE data * * @var array */ protected $qb_cache_where = array(); /** * QB Cache GROUP BY data * * @var array */ protected $qb_cache_groupby = array(); /** * QB Cache HAVING data * * @var array */ protected $qb_cache_having = array(); /** * QB Cache ORDER BY data * * @var array */ protected $qb_cache_orderby = array(); /** * QB Cache data sets * * @var array */ protected $qb_cache_set = array(); /** * QB No Escape data * * @var array */ protected $qb_no_escape = array(); /** * QB Cache No Escape data * * @var array */ protected $qb_cache_no_escape = array(); // -------------------------------------------------------------------- /** * Select * * Generates the SELECT portion of the query * * @param string * @param mixed * @return CI_DB_query_builder */ public function select($select = '*', $escape = NULL) { if (is_string($select)) { $select = explode(',', $select); } // If the escape value was not set, we will base it on the global setting is_bool($escape) OR $escape = $this->_protect_identifiers; foreach ($select as $val) { $val = trim($val); if ($val !== '') { $this->qb_select[] = $val; $this->qb_no_escape[] = $escape; if ($this->qb_caching === TRUE) { $this->qb_cache_select[] = $val; $this->qb_cache_exists[] = 'select'; $this->qb_cache_no_escape[] = $escape; } } } return $this; } // -------------------------------------------------------------------- /** * Select Max * * Generates a SELECT MAX(field) portion of a query * * @param string the field * @param string an alias * @return CI_DB_query_builder */ public function select_max($select = '', $alias = '') { return $this->_max_min_avg_sum($select, $alias, 'MAX'); } // -------------------------------------------------------------------- /** * Select Min * * Generates a SELECT MIN(field) portion of a query * * @param string the field * @param string an alias * @return CI_DB_query_builder */ public function select_min($select = '', $alias = '') { return $this->_max_min_avg_sum($select, $alias, 'MIN'); } // -------------------------------------------------------------------- /** * Select Average * * Generates a SELECT AVG(field) portion of a query * * @param string the field * @param string an alias * @return CI_DB_query_builder */ public function select_avg($select = '', $alias = '') { return $this->_max_min_avg_sum($select, $alias, 'AVG'); } // -------------------------------------------------------------------- /** * Select Sum * * Generates a SELECT SUM(field) portion of a query * * @param string the field * @param string an alias * @return CI_DB_query_builder */ public function select_sum($select = '', $alias = '') { return $this->_max_min_avg_sum($select, $alias, 'SUM'); } // -------------------------------------------------------------------- /** * SELECT [MAX|MIN|AVG|SUM]() * * @used-by select_max() * @used-by select_min() * @used-by select_avg() * @used-by select_sum() * * @param string $select Field name * @param string $alias * @param string $type * @return CI_DB_query_builder */ protected function _max_min_avg_sum($select = '', $alias = '', $type = 'MAX') { if ( ! is_string($select) OR $select === '') { $this->display_error('db_invalid_query'); } $type = strtoupper($type); if ( ! in_array($type, array('MAX', 'MIN', 'AVG', 'SUM'))) { show_error('Invalid function type: '.$type); } if ($alias === '') { $alias = $this->_create_alias_from_table(trim($select)); } $sql = $type.