cubrid_lob2_seek

(PECL CUBRID >= 8.4.1)

cubrid_lob2_seek — Move the cursor of a lob object.

说明

bool cubrid_lob2_seek ( resource $lob_identifier , int $offset [, int $origin = CUBRID_CURSOR_CURRENT ] )

The cubrid_lob2_seek() function is used to move the cursor position of a lob object by the value set in the offset argument, to the direction set in the origin argument.

To set the origin argument, you can use CUBRID_CURSOR_FIRST to set the cursor position moving forward offset units from the first beginning. In this case, offset must be a positive value.

If you use CUBRID_CURSOR_CURRENT for origin, you can move forward or backward. and offset can be positive or negative.

If you use CUBRID_CURSOR_LAST for origin, you can move backward offset units from the end of LOB object and offset only can be positive.

参数

lob_identifier

Lob identifier as a result of cubrid_lob2_new() or get from the result set.

offset

Number of units you want to move the cursor.

origin

This parameter can be the following values:

CUBRID_CURSOR_FIRST: move forward from the first beginning.

CUBRID_CURSOR_CURRENT: move forward or backward from the current position.

CUBRID_CURSOR_LAST: move backward at the end of LOB object.

返回值

TRUE if the process is successful and FALSE for failure.

范例

Example #1 cubrid_lob2_seek() example

<?php
// test_lob (id INT, contents CLOB)
$conn = cubrid_connect("localhost", 33000, "demodb", "dba", "");

cubrid_execute($conn,"DROP TABLE if exists test_lob");
cubrid_execute($conn,"CREATE TABLE test_lob (id INT, contents CLOB)");
$req = cubrid_prepare($conn, "INSERT INTO test_lob VALUES(2, ?)");

$lob = cubrid_lob2_new($conn, 'CLOB');
$len = cubrid_lob2_write($lob, "Hello world");

cubrid_lob2_seek($lob, 0, CUBRID_CURSOR_LAST);
cubrid_lob2_write($lob, "beautiful");

cubrid_lob2_seek($lob, 15, CUBRID_CURSOR_FIRST);
$data = cubrid_lob2_read($lob, 5);

echo $data."\n";

cubrid_lob2_bind($req, 1, $lob);
cubrid_execute($req);

cubrid_disconnect($conn);
?>

参见