(PHP 5 >= 5.1.0, PHP 7, PECL pdo >= 0.1.0)
PDOStatement::bindParam — 绑定一个参数到指定的变量名
$parameter
, mixed &$variable
[, int $data_type = PDO::PARAM_STR
[, int $length
[, mixed $driver_options
]]] )绑定一个PHP变量到用作预处理的SQL语句中的对应命名占位符或问号占位符。 不同于 PDOStatement::bindValue() ，此变量作为引用被绑定，并只在 PDOStatement::execute() 被调用的时候才取其值。
大多数参数是输入参数，即，参数以只读的方式用来建立查询。一些驱动支持调用存储过程并作为输出参数返回数据，一些支持作为输入/输出参数，既发送数据又接收更新后的数据。
parameter参数标识符。对于使用命名占位符的预处理语句，应是类似 :name 形式的参数名。对于使用问号占位符的预处理语句，应是以1开始索引的参数位置。
variable绑定到 SQL 语句参数的 PHP 变量名。
data_type
使用 PDO::PARAM_* 常量明确地指定参数的类型。要从一个存储过程中返回一个 INOUT 参数，需要为 data_type 参数使用按位或操作符去设置 PDO::PARAM_INPUT_OUTPUT 位。
length数据类型的长度。为表明参数是一个存储过程的 OUT 参数，必须明确地设置此长度。
driver_options
成功时返回 TRUE， 或者在失败时返回 FALSE。
Example #1 执行一条使用命名占位符的预处理语句
<?php
/* 通过绑定的 PHP 变量执行一条预处理语句 */
$calories = 150;
$colour = 'red';
$sth = $dbh->prepare('SELECT name, colour, calories
FROM fruit
WHERE calories < :calories AND colour = :colour');
$sth->bindParam(':calories', $calories, PDO::PARAM_INT);
$sth->bindParam(':colour', $colour, PDO::PARAM_STR, 12);
$sth->execute();
?>
Example #2 执行一条使用问号占位符的预处理语句
<?php
/* 通过绑定的 PHP 变量执行一条预处理语句 */
$calories = 150;
$colour = 'red';
$sth = $dbh->prepare('SELECT name, colour, calories
FROM fruit
WHERE calories < ? AND colour = ?');
$sth->bindParam(1, $calories, PDO::PARAM_INT);
$sth->bindParam(2, $colour, PDO::PARAM_STR, 12);
$sth->execute();
?>
Example #3 使用 INOUT 参数调用一个存储过程
<?php
/* 使用 INOUT 参数调用一个存储过程 */
$colour = 'red';
$sth = $dbh->prepare('CALL puree_fruit(?)');
$sth->bindParam(1, $colour, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT, 12);
$sth->execute();
print("After pureeing fruit, the colour is: $colour");
?>
For those who are confused on insert query using PDO-bindparam:
$sql = $db->prepare("INSERT INTO db_fruit (id, type, colour) VALUES (? ,? ,?)");
$sql->bindParam(1, $newId);
$sql->bindParam(2, $name);
$sql->bindParam(3, $colour);
$sql->execute();
The documentation says this about the length parameter for bindParam:
"To indicate that a parameter is an OUT parameter from a stored procedure, you must explicitly set the length. "
For db2, I found that setting the length for the "INPUT_OUTPUT" parameters causes a problem for varchar parameters that are input parameters. The problem I found is that the stored procedure was called, but varchar input parameters were set to null inside my stored procedure and as a result, the stored procedure could not work properly.
Here is the signature for my stored procedure:
CREATE OR REPLACE PROCEDURE MY_SCHEMA_NAME.MY_STORED_PROCEDURE_NAME ( IN RUN_ID INTEGER,IN V_SCHEMA_NAME VARCHAR(128),
OUT out_rc INTEGER,OUT out_err_message VARCHAR(100),OUT out_sqlstate CHAR(5) ,OUT out_sqlcode INT)
Here is the php code that works:
$command = "Call MY_SCHEMA_NAME.MY_STORED_PROCEDURE_NAME (?,?,?,?,?,?,?)";
$stmt = $this->GuestDb->prepare($command);
$stmt->bindParam(1, $RUN_ID, PDO::PARAM_INT);
$stmt->bindParam(2, $V_SCHEMA_NAME, PDO::PARAM_STR);
$stmt->bindParam(3, $V_TABNAME, PDO::PARAM_STR);
$stmt->bindParam(4, $out_rc, PDO::PARAM_INT|PDO::PARAM_INPUT_OUTPUT);
$stmt->bindParam(5, $out_err_message, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT);
$stmt->bindParam(6, $out_sqlstate, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT);
$stmt->bindParam(7, $out_sqlcode, PDO::PARAM_INT|PDO::PARAM_INPUT_OUTPUT);
Here is the php code that does not work:
$command = "Call MY_SCHEMA_NAME.MY_STORED_PROCEDURE_NAME (?,?,?,?,?,?,?)";
$stmt = $this->GuestDb->prepare($command);
$stmt->bindParam(1, $RUN_ID, PDO::PARAM_INT,12);
$stmt->bindParam(2, $V_SCHEMA_NAME, PDO::PARAM_STR,128);
$stmt->bindParam(3, $V_TABNAME, PDO::PARAM_STR,100);
$stmt->bindParam(4, $out_rc, PDO::PARAM_INT|PDO::PARAM_INPUT_OUTPUT,12);
$stmt->bindParam(5, $out_err_message, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT,100);
$stmt->bindParam(6, $out_sqlstate, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT,6);
$stmt->bindParam(7, $out_sqlcode, PDO::PARAM_INT|PDO::PARAM_INPUT_OUTPUT,12);
MySQL will return an error if a named placeholder has a hyphen in it:
UPDATE wardrobe SET `T-Shirt`=:T-SHIRT WHERE id=:id
Will return the following error: PDOException' with message 'SQLSTATE[HY093]: Invalid parameter number: parameter was not defined'
To resolve, just remove hyphens from named placeholders:
UPDATE wardrobe SET `T-Shirt`=:TSHIRT WHERE id=:id
<?php
/**
* Bind bit value:
*/
$sql = 'SELECT * FROM myTable WHERE level & ?';
$sth = \App::pdo()->prepare($sql);
$sth->bindValue(1, 0b0101, \PDO::PARAM_INT);
$sth->execute();
$result = $sth->fetchAll(\PDO::FETCH_ASSOC);
Avoid to use a param with dot like ":table.column".
It will return a error 'PDOException' with message 'SQLSTATE[HY093]: Invalid parameter number: parameter was not defined' in ...
/*
method for pdo class connection, you can add your cases by yourself and use it.
*/
class Conn{
....
....
private $stmt;
public function bind($parameter, $value, $var_type = null){
if (is_null($var_type)) {
switch (true) {
case is_bool($value):
$var_type = PDO::PARAM_BOOL;
break;
case is_int($value):
$var_type = PDO::PARAM_INT;
break;
case is_null($value):
$var_type = PDO::PARAM_NULL;
break;
default:
$var_type = PDO::PARAM_STR;
}
}
$this->stmt->bindValue($parameter, $value, $var_type);
}
http://technet.microsoft.com/en-us/library/ff628166(v=sql.105).aspx
When binding null data to server columns of type varbinary, binary, or varbinary(max) you should specify binary encoding (PDO::SQLSRV_ENCODING_BINARY) using the $driver_options. See Constants for more information about encoding constants.
Support for PDO was added in version 2.0 of the Microsoft Drivers for PHP for SQL Server.
<?php
$db = new PDO('sqlsrv:server=SQLSERVERNAME;Database=own_exchange', 'user', 'password');
$sql = "INSERT INTO dbo.files(file_name, file_source) VALUES(:file_name, :file_source)";
$stmt = $db->prepare($sql);
$stmt->bindParam(":file_name", $files->name, PDO::PARAM_STR);
$stmt->bindParam(":file_source", file_get_contents($files->tempName), PDO::PARAM_LOB, 0, PDO::SQLSRV_ENCODING_BINARY);
$stmt->execute();
?>
Note that with bindParam the second parameter is passed by reference. This means that the following will produce a warning if E_STRICT is enabled:
<?php
$stmt->bindParam('type', $object->getType());
// Strict Standards: Only variables should be passed by reference in /path/to/file.php on line 123
?>
If the second parameter is not an actual variable, either set the result of $object->getType(); to a variable and use that variable in bindParam or use bindValue instead.
Spent all day banging my head against a brick wall.
Tried to use INOUT or OUT and getting the return variable into PHP using Mysql v5.5.16 on XAMPP.
"MySQL doesn't supporting binding output parameters via its C API. You must use SQL level variables:"
<?php
$stm = $db->prepare("CALL sp_mysp(:Name, :Email, @sp_result)");
$outputArray = $db->query("select @sp_result")->fetch(PDO::FETCH_ASSOC);
?>
So the 'workaround' for Mysql and PDO is to use two SQL calls.
Hope this helps someone.
SQL Server 2008 R2
If this was in the documentation, I didn't stumble across it. When using bound output parameters with a stored procedure, the output parameters are updated AFTER the LAST rowset has been processed.
If your stored procedure does not return any rowsets (no SELECT statements) then you are set, your output parameters will be ready as soon as the stored procedure is processed.
Otherwise you need to process the rows, and then:
<?php $stmt->nextRowset(); ?>
Once that is done for each returning rowset you will have access to the output parameters.
Please note, that PDO format numbers according to current locale. So if, locale set number format to something else, that standard that query WILL NOT work properly.
For example:
in Polish locale (pl_PL) proper decimal separator is coma (","), so: 123,45, not 123.45. If we try bind 123.45 to the query, we will end up with coma in the query.
<?php
setlocale(LC_ALL, 'pl_PL');
$sth = $dbh->prepare('SELECT name FROM products WHERE price < :price');
$sth->bindParam(':price', 123.45, PDO::PARAM_STR);
$sth->execute();
// result:
// SELECT name FROM products WHERE price < '123,45';
?>
This confused me for some time because it is never explicitly mentioned, but PDO will automagically encapsulate parameters for you, so a prepared query that is manually escaped like so:
"INSERT INTO table (column) VALUES (':value');"
Will actually end up being double-quoted and can cause problems.
I know this has been said before but I'll write a note on it too because I think it's important to keep in mind:
If you use PDO bindParam to do a search with a LIKE condition you cannot put the percentages and quotes to the param placeholder '%:keyword%'.
This is WRONG:
"SELECT * FROM `users` WHERE `firstname` LIKE '%:keyword%'";
The CORRECT solution is to leave clean the placeholder like this:
"SELECT * FROM `users` WHERE `firstname` LIKE :keyword";
And then add the percentages to the php variable where you store the keyword:
$keyword = "%".$keyword."%";
And finally the quotes will be automatically added by PDO when executing the query so you don't have to worry about them.
So the full example would be:
<?php
// Get the keyword from query string
$keyword = $_GET['keyword'];
// Prepare the command
$sth = $dbh->prepare('SELECT * FROM `users` WHERE `firstname` LIKE :keyword');
// Put the percentage sing on the keyword
$keyword = "%".$keyword."%";
// Bind the parameter
$sth->bindParam(':keyword', $keyword, PDO::PARAM_STR);
?>
Note that you cannot mix named and positional parameters in one query:
<?php
$stmt = $conn->prepare('SELECT * FROM employees WHERE name LIKE :name OR email LIKE ?');
$name = 'John%';
$email = 'john%';
$stmt->bindParam(':name', $name);
$stmt->bindParam(1, $email);
$stmt->execute();
?>
Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[HY093]: Invalid parameter number: mixed named and positional parameters' in ...
Running PHP 5.3.2 on Linux x86-64
This works ($val by reference):
<?php
foreach ($params as $key => &$val) {
$sth->bindParam($key, $val);
}
?>
This will fail ($val by value, because bindParam needs &$variable):
<?php
foreach ($params as $key => $val) {
$sth->bindParam($key, $val);
}
?>
if you are storing files (or binary data), using PARAM_LOB (and moreover trying to do this with Oracle), don't miss this page :
http://php.net/manual/en/pdo.lobs.php
You will there notice that PDO-PGSQL and PDO-OCI don't work the same at all : not the same argument nor the same behaviour.
Note that when using PDOStatement::bindParam an integer is changed to a string value upon PDOStatement::execute(). (Tested with MySQL).
This can cause problems when trying to compare values using the === operator.
Example:
<?php
$active = 1;
var_dump($active);
$ps->bindParam(":active", $active, PDO::PARAM_INT);
var_dump($active);
$ps->execute();
var_dump($active);
if ($active === 1) {
// do something here
// note: this will fail since $active is now "1"
}
?>
results in:
int(1)
int(1)
string(1) "1"
There seems to be some confusion about whether you can bind a single value to multiple identical placeholders. For example:
$sql = "SELECT * FROM user WHERE is_admin = :myValue AND is_deleted = :myValue ";
$params = array("myValue" => "0");
Some users have reported that attempting to bind a single parameter to multiple placeholders yields a parameter mismatch error in PHP version 5.2.0 and earlier. Starting with version 5.2.1, however, this seems to work just fine.
For details, see bug report 40417:
http://bugs.php.net/bug.php?id=40417
Took me forever to find this elsewhere in the notes in the manual, so I'd thought I'd put this tidbit here to help others in the future.
When using a LIKE search in MySQL along with a prepared statement, the *value* must have the appropriate parentheses attached before the bindParam() statement as such:
<?php
$dbc = $GLOBALS['dbc'];
$sql = "SELECT * FROM `tbl_name` WHERE tbl_col LIKE ?";
$stmt = $dbc->prepare($sql);
$value = "%{$value}%";
$stmt->bindParam($i, $value, PDO::PARAM_STR);
?>
Trying to use
<?php
$stmt->bindParam($i, "%{$value}%", PDO::PARAM_STR);
?>
will fail.
If you're using the MySQL driver and have a stored procedure with an OUT or INOUT parameter, you can't (currently) use bindValue(). See http://bugs.php.net/bug.php?id=35935 for a workaround.
Do not try to use the same named parameter twice in a single SQL statement, for example
<?php
$sql = 'SELECT * FROM some_table WHERE some_value > :value OR some_value < :value';
$stmt = $dbh->prepare($sql);
$stmt->execute( array( ':value' => 3 ) );
?>
...this will return no rows and no error -- you must use each parameter once and only once. Apparently this is expected behavior (according to this bug report: http://bugs.php.net/bug.php?id=33886) because of portability issues.
A caution for those using bindParam() on a placeholder in a
LIKE '%...%' clause, the following code will likely not work:
<?php
$q = "SELECT id, name FROM test WHERE name like '%:foo%'";
$s = "carrot";
$sth = $dbh->prepare($q);
$sth->bindParam(':foo', $s);
$sth->execute();
?>
What is needed is something like the following:
<?php
$s = "%$s%";
$sth->bindParam(':foo', $s);
?>
This should work. Tested against mysql 4.1, PHP 5.1.3.