(PECL ibm_db2 >= 1.0.0)
db2_bind_param — Binds a PHP variable to an SQL statement parameter
$stmt
, int $parameter_number
, string $variable_name
, int $parameter_type
= ?
, int $data_type
= 0
, int $precision
= -1
, int $scale
= 0
) : boolBinds a PHP variable to an SQL statement parameter in a statement resource returned by db2_prepare(). This function gives you more control over the parameter type, data type, precision, and scale for the parameter than simply passing the variable as part of the optional input array to db2_execute().
stmt
A prepared statement returned from db2_prepare().
parameter_number
Specifies the 1-indexed position of the parameter in the prepared statement.
variable_name
A string specifying the name of the PHP variable to bind to the
parameter specified by parameter_number
.
parameter_type
A constant specifying whether the PHP variable should be bound to the
SQL parameter as an input parameter (DB2_PARAM_IN
),
an output parameter (DB2_PARAM_OUT
), or as a
parameter that accepts input and returns output
(DB2_PARAM_INOUT
). To avoid memory overhead, you can
also specify DB2_PARAM_FILE
to bind the PHP variable
to the name of a file that contains large object (BLOB, CLOB, or DBCLOB)
data.
data_type
A constant specifying the SQL data type that the PHP variable should be
bound as: one of DB2_BINARY
,
DB2_CHAR
, DB2_DOUBLE
, or
DB2_LONG
.
precision
Specifies the precision with which the variable should be bound to the database. This parameter can also be used for retrieving XML output values from stored procedures. A non-negative value specifies the maximum size of the XML data that will be retrieved from the database. If this parameter is not used, a default of 1MB will be assumed for retrieving the XML output value from the stored procedure.
scale
Specifies the scale with which the variable should be bound to the database.
成功时返回 true
, 或者在失败时返回 false
。
Example #1 Binding PHP variables to a prepared statement
The SQL statement in the following example uses two input parameters in
the WHERE clause. We call db2_bind_param() to bind two
PHP variables to the corresponding SQL parameters. Notice that the PHP
variables do not have to be declared or assigned before the call to
db2_bind_param(); in the example,
$lower_limit
is assigned a value before the call to
db2_bind_param(), but $upper_limit
is assigned a value after the call to
db2_bind_param(). The variables must be bound and, for
parameters that accept input, must have any value assigned, before calling
db2_execute().
<?php
$sql = 'SELECT name, breed, weight FROM animals
WHERE weight > ? AND weight < ?';
$conn = db2_connect($database, $user, $password);
$stmt = db2_prepare($conn, $sql);
// We can declare the variable before calling db2_bind_param()
$lower_limit = 1;
db2_bind_param($stmt, 1, "lower_limit", DB2_PARAM_IN);
db2_bind_param($stmt, 2, "upper_limit", DB2_PARAM_IN);
// We can also declare the variable after calling db2_bind_param()
$upper_limit = 15.0;
if (db2_execute($stmt)) {
while ($row = db2_fetch_array($stmt)) {
print "{$row[0]}, {$row[1]}, {$row[2]}\n";
}
}
?>
以上例程会输出:
Pook, cat, 3.2 Rickety Ride, goat, 9.7 Peaches, dog, 12.3
Example #2 Calling stored procedures with IN and OUT parameters
The stored procedure match_animal in the following example accepts three different parameters:
an input (IN) parameter that accepts the name of the first animal as input
an input-output (INOUT) parameter that accepts the name of the second
animal as input and returns the string TRUE
if an
animal in the database matches that name
an output (OUT) parameter that returns the sum of the weight of the two identified animals
<?php
$sql = 'CALL match_animal(?, ?, ?)';
$conn = db2_connect($database, $user, $password);
$stmt = db2_prepare($conn, $sql);
$name = "Peaches";
$second_name = "Rickety Ride";
$weight = 0;
db2_bind_param($stmt, 1, "name", DB2_PARAM_IN);
db2_bind_param($stmt, 2, "second_name", DB2_PARAM_INOUT);
db2_bind_param($stmt, 3, "weight", DB2_PARAM_OUT);
print "Values of bound parameters _before_ CALL:\n";
print " 1: {$name} 2: {$second_name} 3: {$weight}\n\n";
if (db2_execute($stmt)) {
print "Values of bound parameters _after_ CALL:\n";
print " 1: {$name} 2: {$second_name} 3: {$weight}\n\n";
print "Results:\n";
while ($row = db2_fetch_array($stmt)) {
print " {$row[0]}, {$row[1]}, {$row[2]}\n";
}
}
?>
以上例程会输出:
Values of bound parameters _before_ CALL: 1: Peaches 2: Rickety Ride 3: 0 Values of bound parameters _after_ CALL: 1: Peaches 2: TRUE 3: 22 Results: Peaches, dog, 12.3 Pook, cat, 3.2 Rickety Ride, goat, 9.7
Example #3 Inserting a binary large object (BLOB) directly from a file
The data for large objects are typically stored in files, such as XML documents or audio files. Rather than reading an entire file into a PHP variable, and then binding that PHP variable into an SQL statement, you can avoid some memory overhead by binding the file directly to the input parameter of your SQL statement. The following example demonstrates how to bind a file directly into a BLOB column.
<?php
$stmt = db2_prepare($conn, "INSERT INTO animal_pictures(picture) VALUES (?)");
$picture = "/opt/albums/spook/grooming.jpg";
$rc = db2_bind_param($stmt, 1, "picture", DB2_PARAM_FILE);
$rc = db2_execute($stmt);
?>