问题
Has anyone ever come across this error: General error: 1390 Prepared statement contains too many placeholders
I just did an import via SequelPro of over 50,000 records and now when I go to view these records in my view (Laravel 4) I get General error: 1390 Prepared statement contains too many placeholders.
The below index() method in my AdminNotesController.php file is what is generating the query and rendering the view.
public function index()
{
$created_at_value = Input::get('created_at_value');
$note_types_value = Input::get('note_types_value');
$contact_names_value = Input::get('contact_names_value');
$user_names_value = Input::get('user_names_value');
$account_managers_value = Input::get('account_managers_value');
if (is_null($created_at_value)) $created_at_value = DB::table('notes')->lists('created_at');
if (is_null($note_types_value)) $note_types_value = DB::table('note_types')->lists('type');
if (is_null($contact_names_value)) $contact_names_value = DB::table('contacts')->select(DB::raw('CONCAT(first_name," ",last_name) as cname'))->lists('cname');
if (is_null($user_names_value)) $user_names_value = DB::table('users')->select(DB::raw('CONCAT(first_name," ",last_name) as uname'))->lists('uname');
// In the view, there is a dropdown box, that allows the user to select the amount of records to show per page. Retrieve that value or set a default.
$perPage = Input::get('perPage', 10);
// This code retrieves the order from the session that has been selected by the user by clicking on a table column title. The value is placed in the session via the getOrder() method and is used later in the Eloquent query and joins.
$order = Session::get('account.order', 'company_name.asc');
$order = explode('.', $order);
$notes_query = Note::leftJoin('note_types', 'note_types.id', '=', 'notes.note_type_id')
->leftJoin('users', 'users.id', '=', 'notes.user_id')
->leftJoin('contacts', 'contacts.id', '=', 'notes.contact_id')
->orderBy($order[0], $order[1])
->select(array('notes.*', DB::raw('notes.id as nid')));
if (!empty($created_at_value)) $notes_query = $notes_query->whereIn('notes.created_at', $created_at_value);
$notes = $notes_query->whereIn('note_types.type', $note_types_value)
->whereIn(DB::raw('CONCAT(contacts.first_name," ",contacts.last_name)'), $contact_names_value)
->whereIn(DB::raw('CONCAT(users.first_name," ",users.last_name)'), $user_names_value)
->paginate($perPage)->appends(array('created_at_value' => Input::get('created_at_value'), 'note_types_value' => Input::get('note_types_value'), 'contact_names_value' => Input::get('contact_names_value'), 'user_names_value' => Input::get('user_names_value')));
$notes_trash = Note::onlyTrashed()
->leftJoin('note_types', 'note_types.id', '=', 'notes.note_type_id')
->leftJoin('users', 'users.id', '=', 'notes.user_id')
->leftJoin('contacts', 'contacts.id', '=', 'notes.contact_id')
->orderBy($order[0], $order[1])
->select(array('notes.*', DB::raw('notes.id as nid')))
->get();
$this->layout->content = View::make('admin.notes.index', array(
'notes' => $notes,
'created_at' => DB::table('notes')->lists('created_at', 'created_at'),
'note_types' => DB::table('note_types')->lists('type', 'type'),
'contacts' => DB::table('contacts')->select(DB::raw('CONCAT(first_name," ",last_name) as cname'))->lists('cname', 'cname'),
'accounts' => Account::lists('company_name', 'company_name'),
'users' => DB::table('users')->select(DB::raw('CONCAT(first_name," ",last_name) as uname'))->lists('uname', 'uname'),
'notes_trash' => $notes_trash,
'perPage' => $perPage
));
}
Any advice would be appreciated. Thanks.
回答1:
There is limit 65,535 (2^16-1) place holders in MariaDB 5.5 which is supposed to have identical behaviour as MySQL 5.5.
Not sure if relevant, I tested it on PHP 5.5.12 using MySQLi / MySQLND.
回答2:
While I think @The Disintegrator is correct about the placeholders being limited. I would not run 1 query per record.
I have a query that worked fine until I added one more column and now I have 72k placeholders and I get this error. However, that 72k is made up of 9000 rows with 8 columns. Running this query 1 record at a time would take days. (I'm trying to import AdWords data into a DB and it would literally take more than 24 hours to import a days worth of data if I did it 1 record at a time. I tried that first.)
What I would recommend is something of a hack. First either dynamically determine the max number of placeholders you want to allow - i.e. 60k to be safe. Use this number to determine, based on the number of columns, how many complete records you can import/return at once. Create the full array of data for you query. Use a array_chunk and a foreach loop to grab everything you want in the minimum number of queries. Like this:
$maxRecords = 1000;
$sql = 'SELECT * FROM ...';
$qMarks = array_fill(0, $maxInsert, '(?, ...)');
$tmp = $sql . $implode(', ', $qMarks);
foreach (array_chunk($data, $maxRecords) AS $junk=>$dataArray) {
if (count($dataArray) < $maxRecords)) { break; }
// Do your PDO stuff here using $tmp as you SQL statement with all those placeholders - the ?s
}
// Now insert all the leftovers with basically the same code as above except accounting for
// the fact that you have fewer than $maxRecords now.
回答3:
This error only happens when both of the following conditions are met:
- You are using the MySQL Native Driver (mysqlnd) and not the MySQL client library (libmysqlclient)
- You are not emulating prepares.
If you change either one of these factors, this error will not occur. However keep in mind that doing both of these is recommended either for performance or security issues, so I would not recommend this solution for anything but more of a one-time or temporary problem you are having. To prevent this error from occurring, the fix is as simple as:
$dbh->setAttribute(PDO::ATTR_EMULATE_PREPARES, true);
回答4:
Solved this issue by using array_chunk function.
Here is the solution below:
foreach (array_chunk($data,1000) as $t)
{
DB::table('table_name')->insert($t);
}
回答5:
Using Laravel model, copy all 11000 records from sqlite database to mysql database in few seconds. Chunk data array to 500 records:
public function handle(): void
{
$smodel = new Src_model();
$smodel->setTable($this->argument('fromtable'));
$smodel->setConnection('default'); // sqlite database
$src = $smodel::all()->toArray();
$dmodel = new Dst_model();
$dmodel->setTable($this->argument('totable'));
$dmodel->timestamps = false;
$stack = $dmodel->getFields();
$fields = array_shift($stack);
$condb = DB::connection('mysql');
$condb->beginTransaction();
$dmodel::query()->truncate();
$dmodel->fillable($stack);
$srcarr=array_chunk($src,500);
$isOK=true;
foreach($srcarr as $item) {
if (!$dmodel->query()->insert($item)) $isOK=false;
}
if ($isOK) {
$this->notify("Przenieśliśmy tabelę z tabeli : {$this->argument('fromtable')} do tabeli: {$this->argument('totable')}", 'Będzie świeża jak nigdy!');
$condb->commit();
}
else $condb->rollBack();
}
回答6:
My Fix for above issue: On my side when i got this error I fixed it by reducing the the bulk insertion chunk size from 1000 to 800 and it worked for me. Actually there were too many fields in my table and most them contains the details descriptions of size like a complete page text. when i go for there bulk insertion the service caused crashed and through the above error.
回答7:
I think the number of placeholders is limited to 65536 per query (at least in older mysql versions).
I really can't discern what this piece of code is generating. But if it's a gigantic query, There's your problem.
You should generate one query per record to import and put those into a transaction.
来源：https://stackoverflow.com/questions/18100782/import-of-50k-records-in-mysql-gives-general-error-1390-prepared-statement-con