thinkphp-General error: 1364 Field doesn't have a default v

:(
sqlstate[hy000]: general error: 1364 field 'tiezi' doesn't have a default value
错误位置
file: e:\webpage\thinkphp\library\think\db\driver.class.php 　line: 217
trace
#0 e:\webpage\thinkphp\library\think\db\driver.class.php(217): pdostatement->execute()
#1 e:\webpage\thinkphp\library\think\db\driver.class.php(813): think\db\driver->execute('insert into `tb...', false)
#2 e:\webpage\thinkphp\library\think\model.class.php(320): think\db\driver->insert(array, array, false)
#3 e:\webpage\application\home\controller\indexcontroller.class.php(79): think\model->add(array)
#4 [internal function]: home\controller\indexcontroller->posts()
#5 e:\webpage\thinkphp\library\think\app.class.php(164): reflectionmethod->invoke(object(home\controller\indexcontroller))
#6 e:\webpage\thinkphp\library\think\app.class.php(202): think\app::exec()
#7 e:\webpage\thinkphp\library\think\think.class.php(120): think\app::run()
#8 e:\webpage\thinkphp\thinkphp.php(97): think\think::start()
#9 e:\webpage\index.php(13): require('e:\webpage\thin...')
#10 {main}