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(PHP 5, PECL OCI8 >= 1.1.0)
oci_free_statement — 释放关联于语句或游标的所有资源
$statement
)oci_free_statement() 释放关联于 Oracle 游标或语句的资源,该资源是作为 oci_parse() 的结果或者是从 Oracle 取得。
statement
有效的 OCI 语句。
成功时返回 TRUE
, 或者在失败时返回 FALSE
。
[#1] passerbyxp at gmail dot com [2012-12-19 08:37:48]
A freed statement is not "empty()", it's still a resource:
<?php
$con=oci_connect();
$q=oci_parse($con,"SELECT sysdate FROM dual");
var_dump($q); // resource(5) of type (oci8 statement)
var_dump(empty($q)); // bool(false)
var_dump(oci_statement_type($q)); // string(6) "SELECT"
echo "------\n";
oci_execute($q);
var_dump($q); // same as above
var_dump(empty($q));
var_dump(oci_statement_type($q));
echo "------\n";
oci_free_statement($q);
var_dump($q); // resource(5) of type (Unknown)
var_dump(empty($q)); // bool(false)
var_dump(oci_statement_type($q)); // generates warning and returns false
oci_close($con);
?>
So far I can not think of a way to determine if a statement is freed without using an additional flag...
[#2] Jen M. [2008-10-02 11:05:26]
oci_free_statement doesn't always free up cursors. I had a query where I performed the following functions in a loop:
OCIParse
OCIExecute
Oci_fetch_assoc
(Grab some field values)
OciFreeStatement
I didn't specify the use of a cursor, but ran into a "maximum
open cursors exceeded" error. Within my code, I had one "select * from table_with_lobs" query. When I changed the query to be "select a, b, c, from table_with_lobs" (where I specified the actual column names and where those columns were not LOB fields) the error message went away and I didn't have to resort to upping the max_open_cursors value in Oracle.
[#3] rada at instinctive dot it [2008-03-04 08:46:43]
If you are using cursors, make sure to free the statement *and* the cursor, especially if there is a possibility of running the proc/cursor again (e.g. with different parameters).
<?php
oci_execute($stmt);
oci_execute($crsr);
// iterate through cursor...
oci_free_statement($stmt);
oci_free_statement($crsr);
?>
You need to do it explicitly, closing connection for example does not seem to release the cursor.