Laravel 学习笔记之一：备份数据以及数据填充

进行数据备份

1. 新建备份 command

php artisan make:command BackupTables

2. 数据备份代码

    public function handle()
    {
        $tables = ['table_name1', 'table_name2', 'table_name3'];
        foreach ($tables as $k => $v) {
            $data = DB::table($v)->get();
            $file_name = $v . '.json';
            $data_json = json_encode($data, true);
            file_put_contents(__DIR__ . '/../../../database/data/'.$file_name, $data_json);
        }
    }

数据填充

1. 新建填充 command

php artisan make:seeder TablesSeeder

2. 数据填充代码

    public function run()
    {
        $tables = ['table_name1', 'table_name2', 'table_name3'];
        // 先清空数据
        foreach ($tables as $k => $v) {
            DB::statement("truncate table $v;");
        }
        foreach ($tables as $k => $v) {
            $file_name = $v . '.json';
            $data = file_get_contents(__DIR__ . '/../data/'.$file_name);
            $data = json_decode($data, true);
            DB::table($v)->insert($data);
        }
    }

至此，算是大功告成了！但是，今天从线上备份数据，然后本地填充的时候却报错了Doctrine\DBAL\Driver\PDOException::(“SQLSTATE[HY000]: General error: 1390
Prepared statement contains too many placeholders”)。一查，数据条目多，所以导致这个”bug”的出现。搞了一通，改为以下的代码，完美解决！

            .
            .
            .
            $count = count($data);
            if ( $count < 1000 ){
                DB::table($v)->insert($data);
            }else{
                foreach (array_chunk($data, 1000) as $key => $value) {
                    DB::table($v)->insert($value);
                } 
            }
            .
            .
            .