所以我在几年前发现了这个问题/答案，它与我的需求相似，但我认为我并没有正确地理解它。如果由于表单中的可选字段导致$_POST字段计数和数据库字段数不相同，会发生什么？
function insertToDB($params, $db) { //Pass array and db
$fields = array();
$conn = new mysqli('localhost', 'root', 'root', 'db') or die('XXX');
$stmt = $conn->stmt_init();
$stmt->prepare("SELECT * FROM ".$db);
$stmt->execute();
$meta = $stmt->result_metadata();
while ($field = $meta->fetch_field()) {
$fields[] = $field->name;
}
$fields = implode(", ", $fields);
$placeholders = implode(',', array_fill(0, count($params), '?'));
$types = '';
foreach($params as $value) {
$types.= substr(strtolower(gettype($value)), 0, 1);
}
$ins = "INSERT INTO MYDB (".$fields.") VALUES (".$placeholders.")";
$bind_names[] = $types;
for ($i = 0; $i < count($params); $i++) {
$bind_name = 'bind' . $i;
$$bind_name = $params[$i];
$bind_names[] = &$$bind_name;
}
if ($stmt->prepare($ins)) {
call_user_func_array(array($stmt,'bind_param'),$bind_names);
$insresult = $stmt->execute();
}
return $insresult;
$stmt->close();
}
答案 0 :(得分：0)
如果某个字段是可选字段，那么你应该检查是否设置了$ _POST，你可以这样做：
[2015-11-16T21:03:24.749Z] INFO [2680] - [Application update/AppDeployStage0/AppDeployPreHook/03deploy.py] : Starting activity...
[2015-11-16T21:03:27.024Z] INFO [2680] - [Application update/AppDeployStage0/AppDeployPreHook/03deploy.py] : Activity execution failed, because: Collecting psycopg2==2.6.1 (from -r /opt/python/ondeck/app/requirements.txt (line 1))
Using cached psycopg2-2.6.1.tar.gz
Complete output from command python setup.py egg_info:
running egg_info
creating pip-egg-info/psycopg2.egg-info
writing top-level names to pip-egg-info/psycopg2.egg-info/top_level.txt
writing dependency_links to pip-egg-info/psycopg2.egg-info/dependency_links.txt
writing pip-egg-info/psycopg2.egg-info/PKG-INFO
writing manifest file 'pip-egg-info/psycopg2.egg-info/SOURCES.txt'
warning: manifest_maker: standard file '-c' not found
Error: pg_config executable not found.
Please add the directory containing pg_config to the PATH
or specify the full executable path with the option:
python setup.py build_ext --pg-config /path/to/pg_config build ...
or with the pg_config option in 'setup.cfg'.
----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-z20gvx7_/psycopg2
2015-11-16 21:03:27,010 ERROR Error installing dependencies: Command '/opt/python/run/venv/bin/pip install -r /opt/python/ondeck/app/requirements.txt' returned non-zero exit status 1
Traceback (most recent call last):
File "/opt/elasticbeanstalk/hooks/appdeploy/pre/03deploy.py", line 22, in main
install_dependencies()
File "/opt/elasticbeanstalk/hooks/appdeploy/pre/03deploy.py", line 18, in install_dependencies
check_call('%s install -r %s' % (os.path.join(APP_VIRTUAL_ENV, 'bin', 'pip'), requirements_file), shell=True)
File "/usr/lib64/python2.7/subprocess.py", line 540, in check_call
raise CalledProcessError(retcode, cmd)
CalledProcessError: Command '/opt/python/run/venv/bin/pip install -r /opt/python/ondeck/app/requirements.txt' returned non-zero exit status 1 (ElasticBeanstalk::ExternalInvocationError)
caused by: Collecting psycopg2==2.6.1 (from -r /opt/python/ondeck/app/requirements.txt (line 1))
Using cached psycopg2-2.6.1.tar.gz
Complete output from command python setup.py egg_info:
running egg_info
creating pip-egg-info/psycopg2.egg-info
writing top-level names to pip-egg-info/psycopg2.egg-info/top_level.txt
writing dependency_links to pip-egg-info/psycopg2.egg-info/dependency_links.txt
writing pip-egg-info/psycopg2.egg-info/PKG-INFO
writing manifest file 'pip-egg-info/psycopg2.egg-info/SOURCES.txt'
warning: manifest_maker: standard file '-c' not found
Error: pg_config executable not found.
Please add the directory containing pg_config to the PATH
or specify the full executable path with the option:
python setup.py build_ext --pg-config /path/to/pg_config build ...
or with the pg_config option in 'setup.cfg'.
----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-z20gvx7_/psycopg2
2015-11-16 21:03:27,010 ERROR Error installing dependencies: Command '/opt/python/run/venv/bin/pip install -r /opt/python/ondeck/app/requirements.txt' returned non-zero exit status 1
Traceback (most recent call last):
File "/opt/elasticbeanstalk/hooks/appdeploy/pre/03deploy.py", line 22, in main
install_dependencies()
File "/opt/elasticbeanstalk/hooks/appdeploy/pre/03deploy.py", line 18, in install_dependencies
check_call('%s install -r %s' % (os.path.join(APP_VIRTUAL_ENV, 'bin', 'pip'), requirements_file), shell=True)
File "/usr/lib64/python2.7/subprocess.py", line 540, in check_call
raise CalledProcessError(retcode, cmd)
CalledProcessError: Command '/opt/python/run/venv/bin/pip install -r /opt/python/ondeck/app/requirements.txt' returned non-zero exit status 1 (Executor::NonZeroExitStatus)
那样，字段数和mysql数总是一样的，因为它看是否有选择，那么如果它没有为你设置一个。
答案 1 :(得分：0)
从一个快速示例开始，假设您有这些表字段
$table_fields = array('foo', 'bar', 'baz');
您输入的数据如下所示
$input_data = array('foo' => 1,
'bar' => 2);
你可以做的是为每个表字段设置一些默认输入数据（我很懒，所以默认为NULL）
array_fill(0, count($table_fields), NULL)
然后我们将它们与array_combine
array_combine($table_fields, array_fill(0, count($table_fields), NULL))
这样您的输入数据可以使用array_merge覆盖默认值，如下所示
var_dump(
array_merge(
array_combine($table_fields, array_fill(0, count($table_fields), NULL)),
$input_data
)
);
# prints
# array(3) {
# ["foo"]=>
# int(1)
# ["bar"]=>
# int(2)
# ["baz"]=>
# NULL
#}
但是，如果可能，您是否可以尝试将可选字段设为可选字段，以便在CREATE TABLE语句中确保为这些字段设置了默认值？在这种情况下，您还将保存一轮到数据库以查询字段名称（$stmt->prepare("SELECT * FROM ".$db);，如果您确实需要，可能可以使用LIMIT 1来加速它。所以改为你的这一行
$ins = "INSERT INTO MYDB (".$fields.") VALUES (".$placeholders.")";
将成为
$ins = "INSERT INTO MYDB (".implode(",", array_keys($params)).") VALUES (".$placeholders.")";