分享自己封装的mysql类 基于pdo

由于经常开发小型系统用不到框架，用原生写又太麻烦干脆封装一个MySQL操作类
用了连贯操作 用法和tp相似 上手快 Db.zip

用法

        $res = Db::table('tbl_user')->where('id', 1)->find();   // 获取单个数据
        $res = Db::table('tbl_user')->order('id', 'desc')->select();     // 获取结果集 排序
        $res = Db::instance()->getLastSql();       // 获取上次执行的sql
        $res = Db::table("tbl_user")->where('id', 2)->update(['name' => '云青']);      // 更新数据
        $res = Db::table("tbl_user")->insert(['account' => 'acc', 'name' => 123]);       // 插入单个数据 并返回插入id
        $res = Db::table("tbl_user")
            ->insertAll(
                [
                    ['account' => 'test1', 'name' => 'test1'], 
                    ['account' => 'test2', 'name' => 'test2']
                ]
            );       // 批量插入数据
        $res = Db::table('tbl_user')->where('id', 5)->delete();       // 删除数据
        $res = Db::table('tbl_user')->tbFields();       // 获取数据表字段
        $res = Db::table('tbl_user')->count('id');      // 统计数据条数
        $res = Db::table('tbl_user')->field('id')->sum();      // 统计id和
        $res = Db::table('tbl_user')->doSql("select * from tbl_user");      // 自定义sql
        $res = Db::instance()->startTrans();        // 开启事务
        $res = Db::table("tbl_user")
            ->insertAll(
                [
                    ['account' => 'test1', 'name' => 'test1'], 
                    ['account' => 'test2', 'test2' => 'test2']
                ]
            );       // 批量插入数据
        $res = Db::instance()->commit();          // 提交
        $res = Db::instance()->rollback();          // 回滚
        $res = Db::table('tbl_user')
            ->field('id')
            ->whereIn('account', 'test1,test2')
            ->where('id', '!=', 2)
            ->select();   // whereIn
        $res = Db::table('tbl_user')    // whereIn
            ->field('id')
            ->whereIn('account', 'test1,test2')
            ->whereIn('name', ['test1', 'test2'], 'or')
            ->where('pmid', '=', 0)
            ->select();

封装类

<?php
/**
 * @author anderyly
 * @email admin@aaayun.cc
 * @link http://vclove.cn/
 * @copyright Copyright (c) 2018
 */

namespace ay\lib;

class Db
{

    private static $db;
    private $dbType = 'mysql';
    private $pConnect = true;
    private static $table;
    private $host;
    private $port;
    private $dbName;
    private $user;
    private $pass;
    private $group = '';
    private static $sql = false; //最后一条sql语句
    private $where = '';
    private $order = '';
    private $limit = '';
    private $field = '*';
    private $clear = 0; //状态，0表示查询条件干净，1表示查询条件污染
    private static $trans = 0; //事务指令数

    /**
     * 初始化
     * Dc constructor.
     * @param null $conf 数据库配置
     */
    public function __construct($conf = null)
    {

        class_exists('PDO') or halt("PDO模块不存在");
        if (is_null($conf)) {
            $conf = C();
        }

        $this->dbType = $conf['DB_TYPE'];
        $this->host = $conf['DB_HOST'];
        $this->port = $conf['DB_PORT'];
        $this->user = $conf['DB_USER'];
        $this->pass = $conf['DB_PASS'];
        $this->dbName = $conf['DB_NAME'];

        //连接数据库
        if (is_null(self::$db)) {
            $this->connect();
        }

    }

    /**
     * PDO连接数据库
     * @throws \Exception
     */
    private function connect()
    {
        $dsn = $this->dbType . ':host=' . $this->host . ';port=' . $this->port . ';dbname=' . $this->dbName;
        $options = $this->pConnect ? [\PDO::ATTR_PERSISTENT => true] : [];
        try {
            $dbh = new \PDO($dsn, $this->user, $this->pass, $options);
            $dbh->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
            $dbh->setAttribute(\PDO::ATTR_EMULATE_PREPARES, false);
        } catch (\PDOException $e) {
            throw new \Exception('Connection failed: ' . $e->getMessage());
        }
        $dbh->exec('SET NAMES utf8');
        self::$db = $dbh;
    }

    /**
     * @return object
     */
    public static function instance()
    {
        return new self();
    }

    /**
     * 设置数据表名
     * @param $table
     * @return object
     */
    public static function name($table)
    {
        if (empty($table)) {
            halt('不能设置数据表名为空');
        }

        $tableS = C('DB_PRE') . $table;
        self::$table = self::addChar($tableS);
        return new self();
    }

    /**
     * 设置数据表名
     * @param $table
     * @return object
     */
    public static function table($table)
    {
        if (empty($table)) {
            halt('不能设置数据表名为空');
        }

        self::$table = self::addChar($table);
        return new self();
    }

    /**
     * 设置当前数据表别名
     * @param $alias
     * @return object
     */
    public function alias($alias): object
    {
        if (empty($alias) or empty(self::$table)) {
            halt('数据库表名设置别名为空');
        }

        self::$table .= ' AS ' . $alias;
        return $this;
    }

    private static function addChar($value, $num = 0)
    {
        if (strpos($value, "`") === false and $num == 1 and !is_int($value)) {
            $data = "'" . trim($value) . "'";
        } else if (strpos($value, "`") === false and !is_int($value) and $num != 1) {
            $data = "`" . trim($value) . "`";
        } else {
            $data = trim($value);
        }
        return $data;
    }

    /**
     * 执行查询 主要针对 SELECT, SHOW 等指令
     * @param string $sql
     * @return mixed
     */
    public function doQuery($sql = '', $options = true)
    {
        self::$sql = $sql;

        if ($options) {
            $result = self::$db->query(self::$sql)->fetchAll(\PDO::FETCH_ASSOC);
        } else {
            $result = self::$db->query(self::$sql)->fetch(\PDO::FETCH_ASSOC);
        }

        return $result;
    }

    /**
     * 执行语句 针对 INSERT, UPDATE 以及DELETE,exec结果返回受影响的行数
     * @param string $sql
     * @return mixed
     */
    public function doExec($sql = '', $op = '')
    {
        self::$sql = $sql;
        $res = self::$db->exec(self::$sql);
        if ($op == 'insert') {
            $res = $this->getLastInsId();
        }
        return $res;
    }

    /**
     * 执行sql语句，自动判断进行查询或者执行操作
     * @param string $sql SQL指令
     * @return mixed
     */
    public function doSql($sql = '')
    {
        $queryIps = 'INSERT|UPDATE|DELETE|REPLACE|CREATE|DROP|LOAD DATA|SELECT .* INTO|COPY|ALTER|GRANT|REVOKE|LOCK|UNLOCK';
        if (preg_match('/^\s*"?(' . $queryIps . ')\s+/i', $sql)) {
            return $this->doExec($sql);
        } else {
            return $this->doQuery($sql);
        }
    }

    /**
     * 获取上一次查询的sql
     * @return string
     */
    public function getLastSql()
    {
        return self::$sql;
    }

    /**
     * 插入方法
     * @param array $data
     * @return mixed
     * @throws \Exception
     */
    public function insert(array $data)
    {
        $data = $this->dataFormat($data);
        if (!$data) {
            exit('插入数据不能为空');
        }

        $sql = 'INSERT INTO ' . self::$table . '(' . implode(',', array_keys($data)) . ') VALUES(' . implode(',', array_values($data)) . ')';
        return $this->doExec($sql, 'insert');
    }

    /**
     * 批量插入方法
     * @param array $data
     * @return mixed
     * @throws \Exception
     */
    public function insertAll(array $data)
    {

        $value = '(';
        foreach ($data as $k => $v) {
            foreach ($v as $k1 => $v1) {
                $value .= "'" . $v1 . "',";
            }
            $value = rtrim($value, ',');
            $value .= '), (';
        }
        $value = rtrim($value, ', (');

        $sql = 'INSERT INTO ' . self::$table . '(' . implode(',', array_keys($data[0])) . ') VALUES ' . $value;
        return $this->doExec($sql, false);
    }

    /**
     * 获取最后一次插入时的ID
     * @return mixed
     */
    public function getLastInsId()
    {
        $sql = 'SELECT LAST_INSERT_ID()';
        $res = $this->doQuery($sql, false);
        return isset($res['LAST_INSERT_ID()']) ? $res['LAST_INSERT_ID()'] : 'false';
    }

    /**
     * 删除方法
     * @return mixed
     * @throws \Exception
     */
    public function delete()
    {
        //安全考虑,阻止全表删除
        if (!trim($this->where)) {
            exit('删除条件禁止为空');
        }

        $sql = 'DELETE FROM ' . self::$table . ' ' . $this->where;
        $this->clear = 1;
        $this->clear();
        return $this->doExec($sql);
    }

    /**
     * 更新方法
     * @param array $data
     * @return mixed|void
     * @throws \Exception
     */
    public function update(array $data)
    {
        //安全考虑,阻止全表更新
        if (!trim($this->where)) {
            exit('更新条件禁止为空');
        }

        $data = $this->dataFormat($data);
        if (!$data) {
            return;
        }

        $valArr = array();
        foreach ($data as $k => $v) {
            $valArr[] = $k . '=' . $v;
        }
        $valStr = implode(',', $valArr);
        $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . trim($valStr) . ' ' . trim($this->where);
        return $this->doExec($sql);
    }

    /**
     * 更新语句 字段值加 $number
     * @param array|string $field
     * @param null $number
     * @return mixed|void
     * @throws \Exception
     */
    public function setInc($field, $number = null)
    {
        //安全考虑,阻止全表更新
        if (!trim($this->where)) {
            exit('更新条件禁止为空');
        }

        if (is_array($field)) {
            $data = $this->dataFormat($field);
            if (!$data) {
                return;
            }

            $valArr = array();
            foreach ($data as $k => $v) {
                $valArr[] = $k . '=' . $k . '+' . $v;
            }
            $valStr = implode(',', $valArr);
            $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . trim($valStr) . ' ' . trim($this->where);
        } else if (is_string($field) and is_null($number)) {
            $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . self::addChar($field) . '=' . self::addChar($field) . '+1 ' . trim($this->where);
        } else {
            $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . self::addChar($field) . '=' . self::addChar($field) . '+' . self::addChar($number, 1) . ' ' . trim($this->where);
        }
        return $this->doExec($sql);

    }

    /**
     * 更新语句 字段值减 $number
     * @param array|string $field
     * @param null $number
     * @return mixed|void
     * @throws \Exception
     */
    public function setDec($field, $number = null)
    {
        //安全考虑,阻止全表更新
        if (!trim($this->where)) {
            exit('更新条件禁止为空');
        }

        if (is_array($field)) {
            $data = $this->dataFormat($field);
            if (!$data) {
                return;
            }

            $valArr = array();
            foreach ($data as $k => $v) {
                $valArr[] = $k . '=' . $k . '-' . $v;
            }
            $valStr = implode(',', $valArr);
            $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . trim($valStr) . ' ' . trim($this->where);
        } else if (is_string($field) and is_null($number)) {
            $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . self::addChar($field) . '=' . self::addChar($field) . '-1 ' . trim($this->where);
        } else {
            $sql = 'UPDATE ' . trim(self::$table) . ' SET ' . self::addChar($field) . '=' . self::addChar($field) . '-' . self::addChar($number, 1) . ' ' . trim($this->where);
        }
        return $this->doExec($sql);

    }

    /**
     * 查询函数
     * @return array|boolean 结果集
     */
    public function select()
    {
        $sql = 'SELECT ' . trim($this->field) . ' FROM ' . self::$table . ' ' . trim($this->where) . ' ' . trim($this->order) . ' ' . trim($this->limit) . " " . trim($this->group);
        $this->clear = 1;
        $this->clear();
        $res = $this->doQuery(trim($sql));
        return isset($res[0]) ? $res : [];
    }

    /**
     * 查询函数
     * @return array|boolean 结果集
     */
    public function find()
    {
        $sql = "SELECT " . trim($this->field) . " FROM " . self::$table . " " . trim($this->where) . " " . trim($this->order) . " " . trim(" LIMIT 1") . " " . trim($this->group);
        $this->clear = 1;
        $this->clear();
        return $this->doQuery(trim($sql), false);

    }

    /**
     * 设置条件
     * @param string | array $option
     * @param string $where
     * @param string $value
     * @return $this
     */
    public function where($option, $where = null, $value = null)
    {
        if ($this->clear > 0) {
            $this->clear();
        }

        // 判断之前是否使用where语句
        if (strpos($this->where, 'WHERE')) {
            $this->where .= ' AND ';
            $useWhere = 1;
        } else {
            $this->where = ' WHERE ';
        }

        // 判断第一个参数为字符
        if (is_string($option)) {
            // 当三个参数都为字符串
            if (!is_null($value)):
                $this->where .= $option . $this->whereTo($where) . $this->addChar($value, 1);
            endif;
            // 当第三个参数不存在
            if (is_null($value)) {
                $this->where .= $option . '=' . $this->addChar($where, 1);
            } else if (is_null($where)) {
                // 当第二个参数不存在
                $this->where .= $option;
            }
        } else if (is_array($option)) {     // 当第一个参数为数组
            $qz = "(";

            foreach ($option as $v) {
                // 当第一个参数循环后为数组
                if (is_array($v)) {
                    if (strstr($this->where, '(')) {
                        $qz = ' ';
                    }
                    if (isset($useWhere)) {
                        $qz = '(';
                        unset($useWhere);
                    }
                    $condition = $qz . $this->addChar($v[0], 'where') . ' ' . $v[1] . ' ' . $this->addChar($v[2], 1);
                } else {
                    $this->where .= ' ' . $this->addChar($option[0]) . $option[1] . $option[2];
                    $cc = 1;
                    break;
                }
                $logIc = isset($v[3]) ? ' ' . $v[3] : ' AND';
                $this->where .= isset($mark) ? $logIc . $condition : $condition;
                $mark = 1;
            }
            if (!isset($cc)) {
                $this->where .= ')';
            }
        }
        return $this;
    }

    private function whereTo($field)
    {
        switch ($field) {
            case ($field == 'neq' or $field == '!='):
                return '!=';
            case ($field == 'eq' or $field == '='):
                return '=';
            case ($field == 'like' or $field == '%'):
                return 'LIKE';
            default:
                return $field;
        }
    }

    /**
     * 设置条件
     * @param string $option
     * @param string | array $value
     * @return $this
     */
    public function whereIn($option, $value, $tj = 'AND')
    {
        if ($this->clear > 0) {
            $this->clear();
        }

        // 判断之前是否使用where语句
        if (strpos($this->where, 'WHERE')) {
            $this->where .= ' ' . $tj . ' ';
            $useWhere = 1;
        } else {
            $this->where = ' WHERE ';
        }
        $arr = explode(',', $value);
        $str = '';
        foreach ($arr as $v) {
            $str .= $this->addChar($v, 1) . ',';
        }
        $str = rtrim($str, ',');

        // 判断第一个参数为字符
        if (is_string($value)) {
            $this->where .= $option . " IN (" . $str . ")";
        } else if (is_array($value)) {
            $str = '';
            foreach ($value as $v) {
                $str .= $this->addChar($v, 1) . ',';
            }
            $str = rtrim($str, ',');
            $this->where .= $option . " IN (" . $str . ")";
        }
        return $this;
    }

    /**
     * 设置条件
     * @param $option
     * @param string $where
     * @param string $value
     * @return $this
     */
    public function whereOr($option, $where = null, $value = null)
    {
        if ($this->clear > 0) {
            $this->clear();
        }

        if (strpos($this->where, 'WHERE')) {
            $this->where .= ' OR ';
            $ss = 1;
        } else {
            $this->where = ' WHERE ';
        }

        if (is_string($option)) {
            if (!is_null($value)):
                $this->where .= $option . $this->whereTo($where) . $this->addChar($value, 1);
            endif;

            if (is_null($value)) {
                $this->where .= $option . '=' . $this->addChar($where, 1);
            } else if (is_null($where)) {
                $this->where .= $option;
            }
        } else if (is_array($option)) {
            $qz = '(';
            foreach ($option as $v) {
                $logIc = ' AND';
                if (is_array($v)) {
                    if (strstr($this->where, '(')) {
                        $qz = ' ';
                    }
                    if (isset($ss)) {
                        $qz = '(';
                        unset($ss);
                    }
                    $condition = $qz . $this->addChar($v[0]) . ' ' . $v[1] . ' ' . $this->addChar($v[2], 1);
                } else {
                    $this->where .= ' ' . $this->addChar($option[0]) . $option[1] . $option[2];
                    $cc = 1;
                    break;
                }
                if (isset($v[3]) and ($v[3] == 'or' or $v[3] == 'OR')) {
                    $logIc = ' OR';
                    $this->where .= isset($mark) ? $logIc . $condition : $condition;
                } else {
                    $this->where .= isset($mark) ? $logIc . $condition : $condition;
                }

                $mark = 1;
            }
            if (!isset($cc)) {
                $this->where .= ')';
            }

        }

        return $this;
    }

    /**
     * 取得数据表的字段信息
     * @return array
     */
    public function tbFields()
    {
        $sql = 'SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME="' . str_replace('`', '', self::$table) . '" AND TABLE_SCHEMA="' . $this->dbName . '"';
        $res = $this->doQuery($sql);

        $ret = array();
        foreach ($res as $key => $value) {
            $ret[] = $value['COLUMN_NAME'];
        }
        return $ret;
    }

    /**
     * 过滤并格式化数据表字段
     * @param $data
     * @return array
     */
    public function dataFormat($data)
    {
        if (!is_array($data)) {
            return [];
        }

        $table_column = $this->tbFields();
        $ret = [];
        foreach ($data as $key => $val):
            if (!is_scalar($val)) {
                continue;
            }

            if (array_key_exists($key, $table_column)):
                $key = $this->addChar($key);
                if (is_int($val)) {
                    $val = intval($val);
                } else if (is_float($val)) {
                    $val = floatval($val);
                } else if (preg_match('/^\(\w*(\+|\-|\*|\/)?\w*\)$/i', $val)) {
                    $val = $val;
                } elseif (is_string($val)) {
                    $val = '"' . addslashes($val) . '"';
                }
                $ret[$key] = $val;
            endif;
        endforeach;

        return $ret;
    }

    /**
     * 排序
     * @param $option
     * @param null $sort
     * @return $this
     */
    public function order($option, $sort = null)
    {
        if ($this->clear > 0) {
            $this->clear();
        }

        $this->order = ' ORDER BY ';
        if (!is_null($sort)) {
            $this->order .= $option . ' ' . $sort;
        } else if (is_string($option)) {
            $this->order .= $option;
        } else if (is_array($option)) {
            foreach ($option as $k => $v) {
                $order = $k . " " . $v;
                $this->order .= isset($mark) ? ',' . $order : $order;
                $mark = 1;
            }
        }
        return $this;
    }

    /**
     * @param $option
     * @return $this
     */
    public function group($option)
    {
        if ($this->clear > 0) {
            $this->clear();
        }

        $this->group = ' GROUP BY ' . $option;

        return $this;
    }

    /**
     * 分页
     * @param $page
     * @param null $pageSize
     * @return $this
     */
    public function limit($page, $pageSize = null)
    {
        if ($this->clear > 0) {
            $this->clear();
        }

        if ($pageSize === null) {
            $this->limit = 'LIMIT ' . $page;
        } else {
            $pagEval = intval(($page - 1) * $pageSize);
            $this->limit = 'LIMIT ' . $pagEval . ',' . $pageSize;
        }
        return $this;
    }

    /**
     * 设置字段名
     * @param $field
     * @return $this
     */
    public function field($field)
    {
        if ($this->clear > 0) {
            $this->clear();
        }
        $this->field = $field;
        return $this;
    }

    /**
     * 查询 左右内全
     * @param $tab
     * @param string $where
     * @param string $join
     * @return $this
     */
    public function join($tab, $where = '', $join = 'INNER')
    {
        if ($this->clear > 0) {
            $this->clear();
        }
        if (is_array($tab)) {
            foreach ($tab as $k => $v):
                $table = $k . ' AS ' . $v;
            endforeach;
        } else {
            $table = str_replace(' ', ' AS ', $tab);
        }
        self::$table .= ' ' . $join . ' JOIN ' . $table . ' ON(' . $where . ')';

        return $this;
    }

    /**
     * 计数
     * @return mixed
     */
    public function count()
    {
        if ($this->clear > 0) {
            $this->clear();
        }
        $sql = 'SELECT count(' . trim($this->field) . ') AS ' . trim($this->field) . ' FROM ' . self::$table . ' ' . trim($this->where) . " " . trim($this->order);
        $rows = $this->doQuery($sql, false);
        return $rows[trim($this->field)];
    }

    /**
     * 统计
     * @return mixed
     */
    public function sum()
    {
        if ($this->clear > 0) {
            $this->clear();
        }
        $sql = 'SELECT SUM(' . trim($this->field) . ') AS ' . trim($this->field) . ' FROM ' . self::$table . ' ' . trim($this->where) . " " . trim($this->order);
        $rows = $this->doQuery($sql, false);
        return $rows[trim($this->field)];
    }

    /**
     * 清理标记函数
     */
    private function clear()
    {
        $this->where = '';
        $this->order = '';
        $this->limit = '';
        $this->field = '*';
        $this->clear = 0;
    }

    /**
     * 手动清理标记
     * @return $this
     */
    public function clearKey()
    {
        $this->clear();
        return $this;
    }

    /**
     * 启动事务
     */
    public function startTrans()
    {
        //数据rollback 支持
        if (self::$trans == 0) {
            self::$db->beginTransaction();
        }

        self::$trans++;
        return;
    }

    /**
     * 用于非自动提交状态下面的查询提交
     * @return bool
     */
    public function commit()
    {
        $result = true;
        if (self::$trans > 0) {
            $result = self::$db->commit();
            self::$trans = 0;
        }
        return $result;
    }

    /**
     * 事务回滚
     * @return bool
     */
    public function rollback()
    {
        $result = true;
        if (self::$trans > 0) {
            $result = self::$db->rollback();
            self::$trans = 0;
        }
        return $result;
    }

    /**
     * 关闭连接
     */
    public function close()
    {
        if (!is_null(self::$db)) {
            self::$db = null;
        }

    }

}